Author: "J W McKee" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"J W McKee"' showing total 60 results

Start Over Author "J W McKee"

60 results on '"J W McKee"'

1. Comparing Recent Pulsar Timing Array Results on the Nanohertz Stochastic Gravitational-wave Background

Author: G. Agazie, J. Antoniadis, A. Anumarlapudi, A. M. Archibald, P. Arumugam, S. Arumugam, Z. Arzoumanian, J. Askew, S. Babak, M. Bagchi, M. Bailes, A.-S. Bak Nielsen, P. T. Baker, C. G. Bassa, A. Bathula, B. Bécsy, A. Berthereau, N. D. R. Bhat, L. Blecha, M. Bonetti, E. Bortolas, A. Brazier, P. R. Brook, M. Burgay, S. Burke-Spolaor, R. Burnette, R. N. Caballero, A. Cameron, R. Case, A. Chalumeau, D. J. Champion, S. Chanlaridis, M. Charisi, S. Chatterjee, K. Chatziioannou, B. D. Cheeseboro, S. Chen, Z.-C. Chen, I. Cognard, T. Cohen, W. A. Coles, J. M. Cordes, N. J. Cornish, F. Crawford, H. T. Cromartie, K. Crowter, M. Curyło, C. J. Cutler, S. Dai, S. Dandapat, D. Deb, M. E. DeCesar, D. DeGan, P. B. Demorest, H. Deng, S. Desai, G. Desvignes, L. Dey, N. Dhanda-Batra, V. Di Marco, T. Dolch, B. Drachler, C. Dwivedi, J. A. Ellis, M. Falxa, Y. Feng, R. D. Ferdman, E. C. Ferrara, W. Fiore, E. Fonseca, A. Franchini, G. E. Freedman, J. R. Gair, N. Garver-Daniels, P. A. Gentile, K. A. Gersbach, J. Glaser, D. C. Good, B. Goncharov, A. Gopakumar, E. Graikou, J.-M. Griessmeier, L. Guillemot, K. Gültekin, Y. J. Guo, Y. Gupta, K. Grunthal, J. S. Hazboun, S. Hisano, G. B. Hobbs, S. Hourihane, H. Hu, F. Iraci, K. Islo, D. Izquierdo-Villalba, J. Jang, J. Jawor, G. H. Janssen, R. J. Jennings, A. Jessner, A. D. Johnson, M. L. Jones, B. C. Joshi, A. R. Kaiser, D. L. Kaplan, A. Kapur, F. Kareem, R. Karuppusamy, E. F. Keane, M. J. Keith, L. Z. Kelley, M. Kerr, J. S. Key, D. Kharbanda, T. Kikunaga, T. C. Klein, N. Kolhe, M. Kramer, M. A. Krishnakumar, A. Kulkarni, N. Laal, K. Lackeos, M. T. Lam, W. G. Lamb, B. B. Larsen, T. J. W. Lazio, K. J. Lee, Y. Levin, N. Lewandowska, T. B. Littenberg, K. Liu, T. Liu, Y. Liu, A. Lommen, D. R. Lorimer, M. E. Lower, J. Luo, R. Luo, R. S. Lynch, A. G. Lyne, C.-P. Ma, Y. Maan, D. R. Madison, R. A. Main, R. N. Manchester, R. Mandow, M. A. Mattson, A. McEwen, J. W. McKee, M. A. McLaughlin, N. McMann, B. W. Meyers, P. M. Meyers, M. B. Mickaliger, M. Miles, C. M. F. Mingarelli, A. Mitridate, P. Natarajan, R. S. Nathan, C. Ng, D. J. Nice, I. C. Niţu, K. Nobleson, S. K. Ocker, K. D. Olum, S. Osłowski, A. K. Paladi, A. Parthasarathy, T. T. Pennucci, B. B. P. Perera, D. Perrodin, A. Petiteau, P. Petrov, N. S. Pol, N. K. Porayko, A. Possenti, T. Prabu, H. Quelquejay Leclere, H. A. Radovan, P. Rana, S. M. Ransom, P. S. Ray, D. J. Reardon, A. F. Rogers, J. D. Romano, C. J. Russell, A. Samajdar, S. A. Sanidas, S. C. Sardesai, A. Schmiedekamp, C. Schmiedekamp, K. Schmitz, L. Schult, A. Sesana, G. Shaifullah, R. M. Shannon, B. J. Shapiro-Albert, X. Siemens, J. Simon, J. Singha, M. S. Siwek, L. Speri, R. Spiewak, A. Srivastava, I. H. Stairs, B. W. Stappers, D. R. Stinebring, K. Stovall, J. P. Sun, M. Surnis, S. C. Susarla, A. Susobhanan, J. K. Swiggum, K. Takahashi, P. Tarafdar, J. Taylor, S. R. Taylor, G. Theureau, E. Thrane, N. Thyagarajan, C. Tiburzi, L. Toomey, J. E. Turner, C. Unal, M. Vallisneri, E. van der Wateren, R. van Haasteren, A. Vecchio, V. Venkatraman Krishnan, J. P. W. Verbiest, S. J. Vigeland, H. M. Wahl, S. Wang, Q. Wang, C. A. Witt, J. Wang, L. Wang, K. E. Wayt, Z. Wu, O. Young, L. Zhang, S. Zhang, X.-J. Zhu, A. Zic, and The International Pulsar Timing Array Collaboration
Subjects: Gravitational waves, Pulsars, Astrophysics, QB460-466
Abstract: The Australian, Chinese, European, Indian, and North American pulsar timing array (PTA) collaborations recently reported, at varying levels, evidence for the presence of a nanohertz gravitational-wave background (GWB). Given that each PTA made different choices in modeling their data, we perform a comparison of the GWB and individual pulsar noise parameters across the results reported from the PTAs that constitute the International Pulsar Timing Array (IPTA). We show that despite making different modeling choices, there is no significant difference in the GWB parameters that are measured by the different PTAs, agreeing within 1 σ . The pulsar noise parameters are also consistent between different PTAs for the majority of the pulsars included in these analyses. We bridge the differences in modeling choices by adopting a standardized noise model for all pulsars and PTAs, finding that under this model there is a reduction in the tension in the pulsar noise parameters. As part of this reanalysis, we “extended” each PTA’s data set by adding extra pulsars that were not timed by that PTA. Under these extensions, we find better constraints on the GWB amplitude and a higher signal-to-noise ratio for the Hellings–Downs correlations. These extensions serve as a prelude to the benefits offered by a full combination of data across all pulsars in the IPTA, i.e., the IPTA’s Data Release 3, which will involve not just adding in additional pulsars but also including data from all three PTAs where any given pulsar is timed by more than a single PTA.
Published: 2024
Full Text: View/download PDF

2. The Green Bank North Celestial Cap Survey. IX. Timing Follow-up for 128 Pulsars

Author: A. E. McEwen, J. K. Swiggum, D. L. Kaplan, C. M. Tan, B. W. Meyers, E. Fonseca, G. Y. Agazie, P. Chawla, K. Crowter, M. E. DeCesar, T. Dolch, F. A. Dong, W. Fiore, D. C. Good, A. G. Istrate, V. M. Kaspi, V. I. Kondratiev, J. van Leeuwen, L. Levin, E. F. Lewis, R. S. Lynch, K. W. Masui, J. W. McKee, M. A. McLaughlin, H. Al Noori, E. Parent, S. M. Ransom, X. Siemens, R. Spiewak, and I. H. Stairs
Subjects: Radio pulsars, Binary pulsars, Astrophysics, QB460-466
Abstract: The Green Bank North Celestial Cap survey is one of the largest and most sensitive searches for pulsars and transient radio objects. Observations for the survey have finished; priorities have shifted toward long-term monitoring of its discoveries. In this study, we have developed a pipeline to handle large data sets of archival observations and connect them to recent, high-cadence observations taken using the Canadian Hydrogen Intensity Mapping Experiment telescope. This pipeline handles data for 128 pulsars and has produced measurements of spin, positional, and orbital parameters that connect data over observation gaps as large as 2000 days. We have also measured glitches in the timing residuals for five of the pulsars included and proper motion for 19 sources (13 new). We include updates to orbital parameters for 19 pulsars, including nine previously unpublished binaries. For two of these binaries, we provide updated measurements of post-Keplerian binary parameters, which result in much more precise estimates of the total masses of both systems. For PSR J0509+3801, the much improved measurement of the Einstein delay yields much improved mass measurements for the pulsar and its companion, 1.399(6) M _⊙ and 1.412(6) M _⊙ , respectively. For this system, we have also obtained a measurement of the orbital decay due to the emission of gravitational waves, ${\dot{P}}_{{\rm{B}}}=-1.37(7)\times {10}^{-12}$ , which is in agreement with the rate predicted by general relativity for these masses.
Published: 2024
Full Text: View/download PDF

3. CHIME Discovery of a Binary Pulsar with a Massive Nondegenerate Companion

Author: Bridget C. Andersen, Emmanuel Fonseca, J. W. McKee, B. W. Meyers, Jing Luo, C. M. Tan, I. H. Stairs, Victoria M. Kaspi, M. H. van Kerkwijk, Mohit Bhardwaj, P. J. Boyle, Kathryn Crowter, Paul B. Demorest, Fengqiu A. Dong, Deborah C. Good, Jane F. Kaczmarek, Calvin Leung, Kiyoshi W. Masui, Arun Naidu, Cherry Ng, Chitrang Patel, Aaron B. Pearlman, Ziggy Pleunis, Masoud Rafiei-Ravandi, Mubdi Rahman, Scott M. Ransom, Kendrick M. Smith, and Shriharsh P. Tendulkar
Subjects: Radio pulsars, Binary pulsars, Compact binary stars, Pulsars, Neutron stars, Be stars, Astrophysics, QB460-466
Abstract: Of the more than 3000 radio pulsars currently known, only ∼300 are in binary systems, and only five of these consist of young pulsars with massive nondegenerate companions. We present the discovery and initial timing, accomplished using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope, of the sixth such binary pulsar, PSR J2108+4516, a 0.577 s radio pulsar in a 269 day orbit of eccentricity 0.09 with a companion of minimum mass 11 M _⊙ . Notably, the pulsar undergoes periods of substantial eclipse, disappearing from the CHIME 400–800 MHz observing band for a large fraction of its orbit, and displays significant dispersion measure and scattering variations throughout its orbit, pointing to the possibility of a circumstellar disk or very dense stellar wind associated with the companion star. Subarcsecond resolution imaging with the Karl G. Jansky Very Large Array unambiguously demonstrates that the companion is a bright, V ≃ 11 OBe star, EM* UHA 138, located at a distance of 3.26(14) kpc. Archival optical observations of EM* UHA 138 approximately suggest a companion mass ranging from 17.5 M _⊙ < M _c < 23 M _⊙ , in turn constraining the orbital inclination angle to 50.°3 ≲ i ≲ 58.°3. With further multiwavelength follow-up, PSR J2108+4516 promises to serve as another rare laboratory for the exploration of companion winds, circumstellar disks, and short-term evolution through extended-body orbital dynamics.
Published: 2023
Full Text: View/download PDF

4. Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run

Author: R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, N. Adhikari, R. X. Adhikari, V. B. Adya, C. Affeldt, D. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, T. Akutsu, S. Albanesi, A. Allocca, P. A. Altin, A. Amato, C. Anand, S. Anand, A. Ananyeva, S. B. Anderson, W. G. Anderson, M. Ando, T. Andrade, N. Andres, T. Andrić, S. V. Angelova, S. Ansoldi, J. M. Antelis, S. Antier, S. Appert, Koji Arai, Koya Arai, Y. Arai, S. Araki, A. Araya, M. C. Araya, J. S. Areeda, M. Arène, N. Aritomi, N. Arnaud, S. M. Aronson, K. G. Arun, H. Asada, Y. Asali, G. Ashton, Y. Aso, M. Assiduo, S. M. Aston, P. Astone, F. Aubin, C. Austin, S. Babak, F. Badaracco, M. K. M. Bader, C. Badger, S. Bae, Y. Bae, A. M. Baer, S. Bagnasco, Y. Bai, M. Bailes, L. Baiotti, J. Baird, R. Bajpai, M. Ball, G. Ballardin, S. W. Ballmer, A. Balsamo, G. Baltus, S. Banagiri, D. Bankar, J. C. Barayoga, C. Barbieri, B. C. Barish, D. Barker, P. Barneo, F. Barone, B. Barr, L. Barsotti, M. Barsuglia, D. Barta, J. Bartlett, M. A. Barton, I. Bartos, R. Bassiri, A. Basti, M. Bawaj, J. C. Bayley, A. C. Baylor, M. Bazzan, B. Bécsy, V. M. Bedakihale, M. Bejger, I. Belahcene, V. Benedetto, D. Beniwal, T. F. Bennett, J. D. Bentley, M. BenYaala, F. Bergamin, B. K. Berger, S. Bernuzzi, D. Bersanetti, A. Bertolini, J. Betzwieser, D. Beveridge, R. Bhandare, U. Bhardwaj, D. Bhattacharjee, S. Bhaumik, I. A. Bilenko, G. Billingsley, S. Bini, I. A. Birney, O. Birnholtz, S. Biscans, M. Bischi, S. Biscoveanu, A. Bisht, B. Biswas, M. Bitossi, M.-A. Bizouard, J. K. Blackburn, C. D. Blair, D. G. Blair, R. M. Blair, F. Bobba, N. Bode, M. Boer, G. Bogaert, M. Boldrini, L. D. Bonavena, F. Bondu, E. Bonilla, R. Bonnand, P. Booker, B. A. Boom, R. Bork, V. Boschi, N. Bose, S. Bose, V. Bossilkov, V. Boudart, Y. Bouffanais, A. Bozzi, C. Bradaschia, P. R. Brady, A. Bramley, A. Branch, M. Branchesi, J. E. Brau, M. Breschi, T. Briant, J. H. Briggs, A. Brillet, M. Brinkmann, P. Brockill, A. F. Brooks, J. Brooks, D. D. Brown, S. Brunett, G. Bruno, R. Bruntz, J. Bryant, T. Bulik, H. J. Bulten, A. Buonanno, R. Buscicchio, D. Buskulic, C. Buy, R. L. Byer, L. Cadonati, G. Cagnoli, C. Cahillane, J. Calderón Bustillo, J. D. Callaghan, T. A. Callister, E. Calloni, J. Cameron, J. B. Camp, M. Canepa, S. Canevarolo, M. Cannavacciuolo, K. C. Cannon, H. Cao, Z. Cao, E. Capocasa, E. Capote, G. Carapella, F. Carbognani, J. B. Carlin, M. F. Carney, M. Carpinelli, G. Carrillo, G. Carullo, T. L. Carver, J. Casanueva Diaz, C. Casentini, G. Castaldi, S. Caudill, M. Cavaglià, F. Cavalier, R. Cavalieri, M. Ceasar, G. Cella, P. Cerdá-Durán, E. Cesarini, W. Chaibi, K. Chakravarti, S. Chalathadka Subrahmanya, E. Champion, C.-H. Chan, C. Chan, C. L. Chan, K. Chan, M. Chan, K. Chandra, P. Chanial, S. Chao, P. Charlton, E. A. Chase, E. Chassande-Mottin, C. Chatterjee, Debarati Chatterjee, Deep Chatterjee, M. Chaturvedi, S. Chaty, C. Chen, H. Y. Chen, J. Chen, K. Chen, X. Chen, Y.-B. Chen, Y.-R. Chen, Z. Chen, H. Cheng, C. K. Cheong, H. Y. Cheung, H. Y. Chia, F. Chiadini, C-Y. Chiang, G. Chiarini, R. Chierici, A. Chincarini, M. L. Chiofalo, A. Chiummo, G. Cho, H. S. Cho, R. K. Choudhary, S. Choudhary, N. Christensen, H. Chu, Q. Chu, Y-K. Chu, S. Chua, K. W. Chung, G. Ciani, P. Ciecielag, M. Cieślar, M. Cifaldi, A. A. Ciobanu, R. Ciolfi, F. Cipriano, A. Cirone, F. Clara, E. N. Clark, J. A. Clark, L. Clarke, P. Clearwater, S. Clesse, F. Cleva, E. Coccia, E. Codazzo, P.-F. Cohadon, D. E. Cohen, L. Cohen, M. Colleoni, C. G. Collette, A. Colombo, M. Colpi, C. M. Compton, M. Constancio Jr., L. Conti, S. J. Cooper, P. Corban, T. R. Corbitt, I. Cordero-Carrión, S. Corezzi, K. R. Corley, N. Cornish, D. Corre, A. Corsi, S. Cortese, C. A. Costa, R. Cotesta, M. W. Coughlin, J.-P. Coulon, S. T. Countryman, B. Cousins, P. Couvares, D. M. Coward, M. J. Cowart, D. C. Coyne, R. Coyne, J. D. E. Creighton, T. D. Creighton, A. W. Criswell, M. Croquette, S. G. Crowder, J. R. Cudell, T. J. Cullen, A. Cumming, R. Cummings, L. Cunningham, E. Cuoco, M. Curyło, P. Dabadie, T. Dal Canton, S. Dall’Osso, G. Dálya, A. Dana, L. M. DaneshgaranBajastani, B. D’Angelo, S. Danilishin, S. D’Antonio, K. Danzmann, C. Darsow-Fromm, A. Dasgupta, L. E. H. Datrier, S. Datta, V. Dattilo, I. Dave, M. Davier, G. S. Davies, D. Davis, M. C. Davis, E. J. Daw, R. Dean, D. DeBra, M. Deenadayalan, J. Degallaix, M. De Laurentis, S. Deléglise, V. Del Favero, F. De Lillo, N. De Lillo, W. Del Pozzo, L. M. DeMarchi, F. De Matteis, V. D’Emilio, N. Demos, T. Dent, A. Depasse, R. De Pietri, R. De Rosa, C. De Rossi, R. DeSalvo, R. De Simone, S. Dhurandhar, M. C. Díaz, M. Diaz-Ortiz Jr., N. A. Didio, T. Dietrich, L. Di Fiore, C. Di Fronzo, C. Di Giorgio, F. Di Giovanni, M. Di Giovanni, T. Di Girolamo, A. Di Lieto, B. Ding, S. Di Pace, I. Di Palma, F. Di Renzo, A. K. Divakarla, A. Dmitriev, Z. Doctor, L. D’Onofrio, F. Donovan, K. L. Dooley, S. Doravari, I. Dorrington, M. Drago, J. C. Driggers, Y. Drori, J.-G. Ducoin, P. Dupej, O. Durante, D. D’Urso, P.-A. Duverne, S. E. Dwyer, C. Eassa, P. J. Easter, M. Ebersold, T. Eckhardt, G. Eddolls, B. Edelman, T. B. Edo, O. Edy, A. Effler, S. Eguchi, J. Eichholz, S. S. Eikenberry, M. Eisenmann, R. A. Eisenstein, A. Ejlli, E. Engelby, Y. Enomoto, L. Errico, R. C. Essick, H. Estellés, D. Estevez, Z. Etienne, T. Etzel, M. Evans, T. M. Evans, B. E. Ewing, V. Fafone, H. Fair, S. Fairhurst, A. M. Farah, S. Farinon, B. Farr, W. M. Farr, N. W. Farrow, E. J. Fauchon-Jones, G. Favaro, M. Favata, M. Fays, M. Fazio, J. Feicht, M. M. Fejer, E. Fenyvesi, D. L. Ferguson, A. Fernandez-Galiana, I. Ferrante, T. A. Ferreira, F. Fidecaro, P. Figura, I. Fiori, M. Fishbach, R. P. Fisher, R. Fittipaldi, V. Fiumara, R. Flaminio, E. Floden, H. Fong, J. A. Font, B. Fornal, P. W. F. Forsyth, A. Franke, S. Frasca, F. Frasconi, C. Frederick, J. P. Freed, Z. Frei, A. Freise, R. Frey, P. Fritschel, V. V. Frolov, G. G. Fronzé, Y. Fujii, Y. Fujikawa, M. Fukunaga, M. Fukushima, P. Fulda, M. Fyffe, H. A. Gabbard, B. U. Gadre, J. R. Gair, J. Gais, S. Galaudage, R. Gamba, D. Ganapathy, A. Ganguly, D. Gao, S. G. Gaonkar, B. Garaventa, C. García-Núñez, C. García-Quirós, F. Garufi, B. Gateley, S. Gaudio, V. Gayathri, G.-G. Ge, G. Gemme, A. Gennai, J. George, O. Gerberding, L. Gergely, P. Gewecke, S. Ghonge, Abhirup Ghosh, Archisman Ghosh, Shaon Ghosh, Shrobana Ghosh, B. Giacomazzo, L. Giacoppo, J. A. Giaime, K. D. Giardina, D. R. Gibson, C. Gier, M. Giesler, P. Giri, F. Gissi, J. Glanzer, A. E. Gleckl, P. Godwin, E. Goetz, R. Goetz, N. Gohlke, B. Goncharov, G. González, A. Gopakumar, M. Gosselin, R. Gouaty, D. W. Gould, B. Grace, A. Grado, M. Granata, V. Granata, A. Grant, S. Gras, P. Grassia, C. Gray, R. Gray, G. Greco, A. C. Green, R. Green, A. M. Gretarsson, E. M. Gretarsson, D. Griffith, W. Griffiths, H. L. Griggs, G. Grignani, A. Grimaldi, S. J. Grimm, H. Grote, S. Grunewald, P. Gruning, D. Guerra, G. M. Guidi, A. R. Guimaraes, G. Guixé, H. K. Gulati, H.-K. Guo, Y. Guo, Anchal Gupta, Anuradha Gupta, P. Gupta, E. K. Gustafson, R. Gustafson, F. Guzman, S. Ha, L. Haegel, A. Hagiwara, S. Haino, O. Halim, E. D. Hall, E. Z. Hamilton, G. Hammond, W.-B. Han, M. Haney, J. Hanks, C. Hanna, M. D. Hannam, O. Hannuksela, H. Hansen, T. J. Hansen, J. Hanson, T. Harder, T. Hardwick, K. Haris, J. Harms, G. M. Harry, I. W. Harry, D. Hartwig, K. Hasegawa, B. Haskell, R. K. Hasskew, C.-J. Haster, K. Hattori, K. Haughian, H. Hayakawa, K. Hayama, F. J. Hayes, J. Healy, A. Heidmann, A. Heidt, M. C. Heintze, J. Heinze, J. Heinzel, H. Heitmann, F. Hellman, P. Hello, A. F. Helmling-Cornell, G. Hemming, M. Hendry, I. S. Heng, E. Hennes, J. Hennig, M. H. Hennig, A. G. Hernandez, F. Hernandez Vivanco, M. Heurs, S. Hild, P. Hill, Y. Himemoto, A. S. Hines, Y. Hiranuma, N. Hirata, E. Hirose, W. C. G. Ho, S. Hochheim, D. Hofman, J. N. Hohmann, D. G. Holcomb, N. A. Holland, I. J. Hollows, Z. J. Holmes, K. Holt, D. E. Holz, Z. Hong, P. Hopkins, J. Hough, S. Hourihane, E. J. Howell, C. G. Hoy, D. Hoyland, A. Hreibi, B-H. Hsieh, Y. Hsu, G-Z. Huang, H-Y. Huang, P. Huang, Y-C. Huang, Y.-J. Huang, Y. Huang, M. T. Hübner, A. D. Huddart, B. Hughey, D. C. Y. Hui, V. Hui, S. Husa, S. H. Huttner, R. Huxford, T. Huynh-Dinh, S. Ide, B. Idzkowski, A. Iess, B. Ikenoue, S. Imam, K. Inayoshi, C. Ingram, Y. Inoue, K. Ioka, M. Isi, K. Isleif, K. Ito, Y. Itoh, B. R. Iyer, K. Izumi, V. JaberianHamedan, T. Jacqmin, S. J. Jadhav, S. P. Jadhav, A. L. James, A. Z. Jan, K. Jani, J. Janquart, K. Janssens, N. N. Janthalur, P. Jaranowski, D. Jariwala, R. Jaume, A. C. Jenkins, K. Jenner, C. Jeon, M. Jeunon, W. Jia, H.-B. Jin, G. R. Johns, A. W. Jones, D. I. Jones, J. D. Jones, P. Jones, R. Jones, R. J. G. Jonker, L. Ju, P. Jung, K. Jung, J. Junker, V. Juste, K. Kaihotsu, T. Kajita, M. Kakizaki, C. V. Kalaghatgi, V. Kalogera, B. Kamai, M. Kamiizumi, N. Kanda, S. Kandhasamy, G. Kang, J. B. Kanner, Y. Kao, S. J. Kapadia, D. P. Kapasi, S. Karat, C. Karathanasis, S. Karki, R. Kashyap, M. Kasprzack, W. Kastaun, S. Katsanevas, E. Katsavounidis, W. Katzman, T. Kaur, K. Kawabe, K. Kawaguchi, N. Kawai, T. Kawasaki, F. Kéfélian, D. Keitel, J. S. Key, S. Khadka, F. Y. Khalili, S. Khan, E. A. Khazanov, N. Khetan, M. Khursheed, N. Kijbunchoo, C. Kim, J. C. Kim, J. Kim, K. Kim, W. S. Kim, Y.-M. Kim, C. Kimball, N. Kimura, M. Kinley-Hanlon, R. Kirchhoff, J. S. Kissel, N. Kita, H. Kitazawa, L. Kleybolte, S. Klimenko, A. M. Knee, T. D. Knowles, E. Knyazev, P. Koch, G. Koekoek, Y. Kojima, K. Kokeyama, S. Koley, P. Kolitsidou, M. Kolstein, K. Komori, V. Kondrashov, A. K. H. Kong, A. Kontos, N. Koper, M. Korobko, K. Kotake, M. Kovalam, D. B. Kozak, C. Kozakai, R. Kozu, V. Kringel, N. V. Krishnendu, A. Królak, G. Kuehn, F. Kuei, P. Kuijer, A. Kumar, P. Kumar, Rahul Kumar, Rakesh Kumar, J. Kume, K. Kuns, C. Kuo, H-S. Kuo, Y. Kuromiya, S. Kuroyanagi, K. Kusayanagi, S. Kuwahara, K. Kwak, P. Lagabbe, D. Laghi, E. Lalande, T. L. Lam, A. Lamberts, M. Landry, B. B. Lane, R. N. Lang, J. Lange, B. Lantz, I. La Rosa, A. Lartaux-Vollard, P. D. Lasky, M. Laxen, A. Lazzarini, C. Lazzaro, P. Leaci, S. Leavey, Y. K. Lecoeuche, H. K. Lee, H. M. Lee, H. W. Lee, J. Lee, K. Lee, R. Lee, J. Lehmann, A. Lemaître, M. Leonardi, N. Leroy, N. Letendre, C. Levesque, Y. Levin, J. N. Leviton, K. Leyde, A. K. Y. Li, B. Li, J. Li, K. L. Li, T. G. F. Li, X. Li, C-Y. Lin, F-K. Lin, F-L. Lin, H. L. Lin, L. C.-C. Lin, F. Linde, S. D. Linker, J. N. Linley, T. B. Littenberg, G. C. Liu, J. Liu, K. Liu, X. Liu, F. Llamas, M. Llorens-Monteagudo, R. K. L. Lo, A. Lockwood, L. T. London, A. Longo, D. Lopez, M. Lopez Portilla, M. Lorenzini, V. Loriette, M. Lormand, G. Losurdo, T. P. Lott, J. D. Lough, C. O. Lousto, G. Lovelace, J. F. Lucaccioni, H. Lück, D. Lumaca, A. P. Lundgren, L.-W. Luo, J. E. Lynam, R. Macas, M. MacInnis, D. M. Macleod, I. A. O. MacMillan, A. Macquet, I. Magaña Hernandez, C. Magazzù, R. M. Magee, R. Maggiore, M. Magnozzi, S. Mahesh, E. Majorana, C. Makarem, I. Maksimovic, S. Maliakal, A. Malik, N. Man, V. Mandic, V. Mangano, J. L. Mango, G. L. Mansell, M. Manske, M. Mantovani, M. Mapelli, F. Marchesoni, M. Marchio, F. Marion, Z. Mark, S. Márka, Z. Márka, C. Markakis, A. S. Markosyan, A. Markowitz, E. Maros, A. Marquina, S. Marsat, F. Martelli, I. W. Martin, R. M. Martin, M. Martinez, V. A. Martinez, V. Martinez, K. Martinovic, D. V. Martynov, E. J. Marx, H. Masalehdan, K. Mason, E. Massera, A. Masserot, T. J. Massinger, M. Masso-Reid, S. Mastrogiovanni, A. Matas, M. Mateu-Lucena, F. Matichard, M. Matiushechkina, N. Mavalvala, J. J. McCann, R. McCarthy, D. E. McClelland, P. K. McClincy, S. McCormick, L. McCuller, G. I. McGhee, S. C. McGuire, C. McIsaac, J. McIver, T. McRae, S. T. McWilliams, D. Meacher, M. Mehmet, A. K. Mehta, Q. Meijer, A. Melatos, D. A. Melchor, G. Mendell, A. Menendez-Vazquez, C. S. Menoni, R. A. Mercer, L. Mereni, K. Merfeld, E. L. Merilh, J. D. Merritt, M. Merzougui, S. Meshkov, C. Messenger, C. Messick, P. M. Meyers, F. Meylahn, A. Mhaske, A. Miani, H. Miao, I. Michaloliakos, C. Michel, Y. Michimura, H. Middleton, L. Milano, A. L. Miller, A. Miller, B. Miller, M. Millhouse, J. C. Mills, E. Milotti, O. Minazzoli, Y. Minenkov, N. Mio, Ll. M. Mir, M. Miravet-Tenés, C. Mishra, T. Mishra, T. Mistry, S. Mitra, V. P. Mitrofanov, G. Mitselmakher, R. Mittleman, O. Miyakawa, A. Miyamoto, Y. Miyazaki, K. Miyo, S. Miyoki, Geoffrey Mo, L. M. Modafferi, E. Moguel, K. Mogushi, S. R. P. Mohapatra, S. R. Mohite, I. Molina, M. Molina-Ruiz, M. Mondin, M. Montani, C. J. Moore, J. Moragues, D. Moraru, F. Morawski, A. More, C. Moreno, G. Moreno, Y. Mori, S. Morisaki, Y. Moriwaki, B. Mours, C. M. Mow-Lowry, S. Mozzon, F. Muciaccia, Arunava Mukherjee, D. Mukherjee, Soma Mukherjee, Subroto Mukherjee, Suvodip Mukherjee, N. Mukund, A. Mullavey, J. Munch, E. A. Muñiz, P. G. Murray, R. Musenich, S. Muusse, S. L. Nadji, K. Nagano, S. Nagano, A. Nagar, K. Nakamura, H. Nakano, M. Nakano, R. Nakashima, Y. Nakayama, V. Napolano, I. Nardecchia, T. Narikawa, L. Naticchioni, B. Nayak, R. K. Nayak, R. Negishi, B. F. Neil, J. Neilson, G. Nelemans, T. J. N. Nelson, M. Nery, P. Neubauer, A. Neunzert, K. Y. Ng, S. W. S. Ng, C. Nguyen, P. Nguyen, T. Nguyen, L. Nguyen Quynh, W.-T. Ni, S. A. Nichols, A. Nishizawa, S. Nissanke, E. Nitoglia, F. Nocera, M. Norman, C. North, S. Nozaki, L. K. Nuttall, J. Oberling, B. D. O’Brien, Y. Obuchi, J. O’Dell, E. Oelker, W. Ogaki, G. Oganesyan, J. J. Oh, K. Oh, S. H. Oh, M. Ohashi, N. Ohishi, M. Ohkawa, F. Ohme, H. Ohta, M. A. Okada, Y. Okutani, K. Okutomi, C. Olivetto, K. Oohara, C. Ooi, R. Oram, B. O’Reilly, R. G. Ormiston, N. D. Ormsby, L. F. Ortega, R. O’Shaughnessy, E. O’Shea, S. Oshino, S. Ossokine, C. Osthelder, S. Otabe, D. J. Ottaway, H. Overmier, A. E. Pace, G. Pagano, M. A. Page, G. Pagliaroli, A. Pai, S. A. Pai, J. R. Palamos, O. Palashov, C. Palomba, H. Pan, K. Pan, P. K. Panda, H. Pang, P. T. H. Pang, C. Pankow, F. Pannarale, B. C. Pant, F. H. Panther, F. Paoletti, A. Paoli, A. Paolone, A. Parisi, H. Park, J. Park, W. Parker, D. Pascucci, A. Pasqualetti, R. Passaquieti, D. Passuello, M. Patel, M. Pathak, B. Patricelli, A. S. Patron, S. Patrone, S. Paul, E. Payne, M. Pedraza, M. Pegoraro, A. Pele, F. E. Peña Arellano, S. Penn, A. Perego, A. Pereira, T. Pereira, C. J. Perez, C. Périgois, C. C. Perkins, A. Perreca, S. Perriès, J. Petermann, D. Petterson, H. P. Pfeiffer, K. A. Pham, K. S. Phukon, O. J. Piccinni, M. Pichot, M. Piendibene, F. Piergiovanni, L. Pierini, V. Pierro, G. Pillant, M. Pillas, F. Pilo, L. Pinard, I. M. Pinto, M. Pinto, K. Piotrzkowski, M. Pirello, M. D. Pitkin, E. Placidi, L. Planas, W. Plastino, C. Pluchar, R. Poggiani, E. Polini, D. Y. T. Pong, S. Ponrathnam, P. Popolizio, E. K. Porter, R. Poulton, J. Powell, M. Pracchia, T. Pradier, A. K. Prajapati, K. Prasai, R. Prasanna, G. Pratten, M. Principe, G. A. Prodi, L. Prokhorov, P. Prosposito, L. Prudenzi, A. Puecher, M. Punturo, F. Puosi, P. Puppo, M. Pürrer, H. Qi, V. Quetschke, R. Quitzow-James, F. J. Raab, G. Raaijmakers, H. Radkins, N. Radulesco, P. Raffai, S. X. Rail, S. Raja, C. Rajan, K. E. Ramirez, T. D. Ramirez, A. Ramos-Buades, J. Rana, P. Rapagnani, U. D. Rapol, A. Ray, V. Raymond, N. Raza, M. Razzano, J. Read, L. A. Rees, T. Regimbau, L. Rei, S. Reid, S. W. Reid, D. H. Reitze, P. Relton, A. Renzini, P. Rettegno, M. Rezac, F. Ricci, D. Richards, J. W. Richardson, L. Richardson, G. Riemenschneider, K. Riles, S. Rinaldi, K. Rink, M. Rizzo, N. A. Robertson, R. Robie, F. Robinet, A. Rocchi, S. Rodriguez, L. Rolland, J. G. Rollins, M. Romanelli, R. Romano, C. L. Romel, A. Romero-Rodríguez, I. M. Romero-Shaw, J. H. Romie, S. Ronchini, L. Rosa, C. A. Rose, D. Rosińska, M. P. Ross, S. Rowan, S. J. Rowlinson, S. Roy, Santosh Roy, Soumen Roy, D. Rozza, P. Ruggi, K. Ryan, S. Sachdev, T. Sadecki, J. Sadiq, N. Sago, S. Saito, Y. Saito, K. Sakai, Y. Sakai, M. Sakellariadou, Y. Sakuno, O. S. Salafia, L. Salconi, M. Saleem, F. Salemi, A. Samajdar, E. J. Sanchez, J. H. Sanchez, L. E. Sanchez, N. Sanchis-Gual, J. R. Sanders, A. Sanuy, T. R. Saravanan, N. Sarin, B. Sassolas, H. Satari, S. Sato, T. Sato, O. Sauter, R. L. Savage, T. Sawada, D. Sawant, H. L. Sawant, S. Sayah, D. Schaetzl, M. Scheel, J. Scheuer, M. Schiworski, P. Schmidt, S. Schmidt, R. Schnabel, M. Schneewind, R. M. S. Schofield, A. Schönbeck, B. W. Schulte, B. F. Schutz, E. Schwartz, J. Scott, S. M. Scott, M. Seglar-Arroyo, T. Sekiguchi, Y. Sekiguchi, D. Sellers, A. S. Sengupta, D. Sentenac, E. G. Seo, V. Sequino, A. Sergeev, Y. Setyawati, T. Shaffer, M. S. Shahriar, B. Shams, L. Shao, A. Sharma, P. Sharma, P. Shawhan, N. S. Shcheblanov, S. Shibagaki, M. Shikauchi, R. Shimizu, T. Shimoda, K. Shimode, H. Shinkai, T. Shishido, A. Shoda, D. H. Shoemaker, D. M. Shoemaker, S. ShyamSundar, M. Sieniawska, D. Sigg, L. P. Singer, D. Singh, N. Singh, A. Singha, A. M. Sintes, V. Sipala, V. Skliris, B. J. J. Slagmolen, T. J. Slaven-Blair, J. Smetana, J. R. Smith, R. J. E. Smith, J. Soldateschi, S. N. Somala, K. Somiya, E. J. Son, K. Soni, S. Soni, V. Sordini, F. Sorrentino, N. Sorrentino, H. Sotani, R. Soulard, T. Souradeep, E. Sowell, V. Spagnuolo, A. P. Spencer, M. Spera, R. Srinivasan, A. K. Srivastava, V. Srivastava, K. Staats, C. Stachie, D. A. Steer, J. Steinlechner, S. Steinlechner, D. J. Stops, M. Stover, K. A. Strain, L. C. Strang, G. Stratta, A. Strunk, R. Sturani, A. L. Stuver, S. Sudhagar, V. Sudhir, R. Sugimoto, H. G. Suh, T. Z. Summerscales, H. Sun, L. Sun, S. Sunil, A. Sur, J. Suresh, P. J. Sutton, Takamasa Suzuki, Toshikazu Suzuki, B. L. Swinkels, M. J. Szczepańczyk, P. Szewczyk, M. Tacca, H. Tagoshi, S. C. Tait, H. Takahashi, R. Takahashi, A. Takamori, S. Takano, H. Takeda, M. Takeda, C. J. Talbot, C. Talbot, H. Tanaka, Kazuyuki Tanaka, Kenta Tanaka, Taiki Tanaka, Takahiro Tanaka, A. J. Tanasijczuk, S. Tanioka, D. B. Tanner, D. Tao, L. Tao, E. N. Tapia San Martín, C. Taranto, J. D. Tasson, S. Telada, R. Tenorio, J. E. Terhune, L. Terkowski, M. P. Thirugnanasambandam, M. Thomas, P. Thomas, J. E. Thompson, S. R. Thondapu, K. A. Thorne, E. Thrane, Shubhanshu Tiwari, Srishti Tiwari, V. Tiwari, A. M. Toivonen, K. Toland, A. E. Tolley, T. Tomaru, Y. Tomigami, T. Tomura, M. Tonelli, A. Torres-Forné, C. I. Torrie, I. Tosta e Melo, D. Töyrä, A. Trapananti, F. Travasso, G. Traylor, M. Trevor, M. C. Tringali, A. Tripathee, L. Troiano, A. Trovato, L. Trozzo, R. J. Trudeau, D. S. Tsai, D. Tsai, K. W. Tsang, T. Tsang, J-S. Tsao, M. Tse, R. Tso, K. Tsubono, S. Tsuchida, L. Tsukada, D. Tsuna, T. Tsutsui, T. Tsuzuki, K. Turbang, M. Turconi, D. Tuyenbayev, A. S. Ubhi, N. Uchikata, T. Uchiyama, R. P. Udall, A. Ueda, T. Uehara, K. Ueno, G. Ueshima, C. S. Unnikrishnan, F. Uraguchi, A. L. Urban, T. Ushiba, A. Utina, H. Vahlbruch, G. Vajente, A. Vajpeyi, G. Valdes, M. Valentini, V. Valsan, N. van Bakel, M. van Beuzekom, J. F. J. van den Brand, C. Van Den Broeck, D. C. Vander-Hyde, L. van der Schaaf, J. V. van Heijningen, J. Vanosky, M. H. P. M. van Putten, N. van Remortel, M. Vardaro, A. F. Vargas, V. Varma, M. Vasúth, A. Vecchio, G. Vedovato, J. Veitch, P. J. Veitch, J. Venneberg, G. Venugopalan, D. Verkindt, P. Verma, Y. Verma, D. Veske, F. Vetrano, A. Viceré, S. Vidyant, A. D. Viets, A. Vijaykumar, V. Villa-Ortega, J.-Y. Vinet, A. Virtuoso, S. Vitale, T. Vo, H. Vocca, E. R. G. von Reis, J. S. A. von Wrangel, C. Vorvick, S. P. Vyatchanin, L. E. Wade, M. Wade, K. J. Wagner, R. C. Walet, M. Walker, G. S. Wallace, L. Wallace, S. Walsh, J. Wang, J. Z. Wang, W. H. Wang, R. L. Ward, J. Warner, M. Was, T. Washimi, N. Y. Washington, J. Watchi, B. Weaver, S. A. Webster, M. Weinert, A. J. Weinstein, R. Weiss, C. M. Weller, F. Wellmann, L. Wen, P. Weßels, K. Wette, J. T. Whelan, D. D. White, B. F. Whiting, C. Whittle, D. Wilken, D. Williams, M. J. Williams, A. R. Williamson, J. L. Willis, B. Willke, D. J. Wilson, W. Winkler, C. C. Wipf, T. Wlodarczyk, G. Woan, J. Woehler, J. K. Wofford, I. C. F. Wong, C. Wu, D. S. Wu, H. Wu, S. Wu, D. M. Wysocki, L. Xiao, W-R. Xu, T. Yamada, H. Yamamoto, Kazuhiro Yamamoto, Kohei Yamamoto, T. Yamamoto, K. Yamashita, R. Yamazaki, F. W. Yang, L. Yang, Y. Yang, Yang Yang, Z. Yang, M. J. Yap, D. W. Yeeles, A. B. Yelikar, M. Ying, K. Yokogawa, J. Yokoyama, T. Yokozawa, J. Yoo, T. Yoshioka, Hang Yu, Haocun Yu, H. Yuzurihara, A. Zadrożny, M. Zanolin, S. Zeidler, T. Zelenova, J.-P. Zendri, M. Zevin, M. Zhan, H. Zhang, J. Zhang, L. Zhang, T. Zhang, Y. Zhang, C. Zhao, G. Zhao, Y. Zhao, Yue Zhao, R. Zhou, Z. Zhou, X. J. Zhu, Z.-H. Zhu, M. E. Zucker, J. Zweizig, The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, D. Antonopoulou, Z. Arzoumanian, A. Basu, S. Bogdanov, I. Cognard, K. Crowter, T. Enoto, C. M. Espinoza, C. M. L. Flynn, E. Fonseca, D. C. Good, L. Guillemot, S. Guillot, A. K. Harding, M. J. Keith, L. Kuiper, M. E. Lower, A. G. Lyne, J. W. McKee, B. W. Meyers, C. Ng, J. L. Palfreyman, R. M. Shannon, B. Shaw, I. H. Stairs, B. W. Stappers, C. M. Tan, G. Theureau, and P. Weltevrede
Subjects: Gravitational wave astronomy, Neutron stars, Pulsars, Astrophysics, QB460-466
Abstract: Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo’s third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours–months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets.
Published: 2022
Full Text: View/download PDF

5. Strong-Field Gravity Tests with the Double Pulsar

Author: M. Kramer, I. H. Stairs, R. N. Manchester, N. Wex, A. T. Deller, W. A. Coles, M. Ali, M. Burgay, F. Camilo, I. Cognard, T. Damour, G. Desvignes, R. D. Ferdman, P. C. C. Freire, S. Grondin, L. Guillemot, G. B. Hobbs, G. Janssen, R. Karuppusamy, D. R. Lorimer, A. G. Lyne, J. W. McKee, M. McLaughlin, L. E. Münch, B. B. P. Perera, N. Pol, A. Possenti, J. Sarkissian, B. W. Stappers, and G. Theureau
Subjects: Physics, QC1-999
Abstract: Continued timing observations of the double pulsar PSR J0737–3039A/B, which consists of two active radio pulsars (A and B) that orbit each other with a period of 2.45 h in a mildly eccentric (e=0.088) binary system, have led to large improvements in the measurement of relativistic effects in this system. With a 16-yr data span, the results enable precision tests of theories of gravity for strongly self-gravitating bodies and also reveal new relativistic effects that have been expected but are now observed for the first time. These include effects of light propagation in strong gravitational fields which are currently not testable by any other method. In particular, we observe the effects of retardation and aberrational light bending that allow determination of the spin direction of the pulsar. In total, we detect seven post-Keplerian parameters in this system, more than for any other known binary pulsar. For some of these effects, the measurement precision is now so high that for the first time we have to take higher-order contributions into account. These include the contribution of the A pulsar’s effective mass loss (due to spin-down) to the observed orbital period decay, a relativistic deformation of the orbit, and the effects of the equation of state of superdense matter on the observed post-Keplerian parameters via relativistic spin-orbit coupling. We discuss the implications of our findings, including those for the moment of inertia of neutron stars, and present the currently most precise test of general relativity’s quadrupolar description of gravitational waves, validating the prediction of general relativity at a level of 1.3×10^{-4} with 95% confidence. We demonstrate the utility of the double pulsar for tests of alternative theories of gravity by focusing on two specific examples and also discuss some implications of the observations for studies of the interstellar medium and models for the formation of the double pulsar system. Finally, we provide context to other types of related experiments and prospects for the future.
Published: 2021
Full Text: View/download PDF

6. Tests of gravitational symmetries with pulsar binary J1713+0747

Author: W W Zhu, G Desvignes, N Wex, R N Caballero, D J Champion, P B Demorest, J A Ellis, G H Janssen, M Kramer, A Krieger, L Lentati, D J Nice, S M Ransom, I H Stairs, B W Stappers, J P W Verbiest, Z Arzoumanian, C G Bassa, M Burgay, I Cognard, K Crowter, T Dolch, R D Ferdman, E Fonseca, M E Gonzalez, E Graikou, L Guillemot, J W T Hessels, A Jessner, G Jones, M L Jones, C Jordan, R Karuppusamy, M T Lam, K Lazaridis, P Lazarus, K J Lee, L Levin, K Liu, A G Lyne, J W McKee, M A McLaughlin, S Osłowski, T Pennucci, D Perrodin, A Possenti, S Sanidas, G Shaifullah, R Smits, K Stovall, J Swiggum, G Theureau, and C Tiburzi
Published: 2018
Full Text: View/download PDF

7. Studying the Solar system with the International Pulsar Timing Array

Author: R N Caballero, Y J Guo, K J Lee, P Lazarus, D J Champion, G Desvignes, M Kramer, K Plant, Z Arzoumanian, M Bailes, C G Bassa, N D R Bhat, A Brazier, M Burgay, S Burke-Spolaor, S J Chamberlin, S Chatterjee, I Cognard, J M Cordes, S Dai, P Demorest, T Dolch, R D Ferdman, E Fonseca, J R Gair, N Garver-Daniels, P Gentile, M E Gonzalez, E Graikou, L Guillemot, G Hobbs, G H Janssen, R Karuppusamy, M J Keith, M Kerr, M T Lam, P D Lasky, T J W Lazio, L Levin, K Liu, A N Lommen, D R Lorimer, R S Lynch, D R Madison, R N Manchester, J W McKee, M A McLaughlin, S T McWilliams, C M F Mingarelli, D J Nice, S Osłowski, N T Palliyaguru, T T Pennucci, B B P Perera, D Perrodin, A Possenti, S M Ransom, D J Reardon, S A Sanidas, A Sesana, G Shaifullah, R M Shannon, X Siemens, J Simon, R Spiewak, I Stairs, B Stappers, D R Stinebring, K Stovall, J K Swiggum, S R Taylor, G Theureau, C Tiburzi, L Toomey, R van Haasteren, W van Straten, J P W Verbiest, J B Wang, X J Zhu, and W W Zhu
Published: 2018
Full Text: View/download PDF

8. Detection of quasi-periodic micro-structure in three millisecond pulsars with the Large European Array for Pulsars

Author: K Liu, J Antoniadis, C G Bassa, S Chen, I Cognard, M Gaikwad, H Hu, J Jang, G H Janssen, R Karuppusamy, M Kramer, K J Lee, R A Main, G Mall, J W McKee, M B Mickaliger, D Perrodin, S A Sanidas, B W Stappers, L Wang, W W Zhu, M Burgay, R Concu, A Corongiu, A Melis, M Pilia, and A Possenti
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Space and Planetary Science, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies, Mathematics
Abstract: We report on the detection of quasi-periodic micro-structure in three millisecond pulsars (MSPs), PSRs J1022+1001, J2145-0750 and J1744-1134, using high time resolution data acquired with the Large European Array for Pulsars at a radio frequency of 1.4 GHz. The occurrence rate of quasi-periodic micro-structure is consistent among pulses with different peak flux densities. Using an auto-correlation analysis, we measure the periodicity and width of the micro-structure in these three pulsars. The detected micro-structure from PSRs J1022+1001 and J1744-1134 is often highly linearly polarised. In PSR J1022+1001, the linear polarisation position angles of micro-structure pulses are in general flat with a small degree of variation. Using these results, we further examine the frequency and rotational period dependency of micro-structure properties established in previous work, along with the angular beaming and temporal modulation models that explains the appearance of micro-structure. We also discuss a possible link of micro-structure to the properties of some of the recently discovered fast radio bursts which exhibit a very similar emission morphology., Comment: 8 pages, 6 figures, 1 table, published in MNRAS
Published: 2022

9. A Pulsar-Based Time-Scale from the International Pulsar Timing Array

Author: G. Hobbs, L. Guo, R. N. Caballero, W. Coles, K. J. Lee, R. N. Manchester, D. J. Reardon, D. Matsakis, M. L. Tong, Z Arzoumanian, M Bailes, C. G. Bassa, N. D. R. Bhat, A. Brazier, S. Burke-Spolaor, D. J. Champion, S. Chatterjee, I. Cognard, S. Dai, G. Desvignes, T Dolch, R. D. Ferdman, E. Graikou, L Guillemot, G H Janssen, M. J. Keith, M Kerr, M Kramer, M T Lam, K Liu, A Lyne, T J W Lazio, R Lynch, J W McKee, M A McLaughlin, C M F Mingarelli, D J Nice, S Oslowski, T T Pennucci, B B P Perera, D Perrodin, A Possenti, C J Russell, S Sanidas, A Sesana, G Shaifullah, R M Shannon, J Simon, R Spiewak, I H Stairs, B W Stappers, J K Swiggum, S R Taylor, G Theureau, L Toomey, R van Haasteren, J B Wang, Y Wang, and X J Zhu
Subjects: Astronomy
Abstract: We have constructed a new time-scale, TT(IPTA16), based on observations of radio pulsars presented in the first data release from the International Pulsar Timing Array (IPTA). We used two analysis techniques with independent estimates of the noise models for the pulsar observations and different algorithms for obtaining the pulsar time-scale. The two analyses agree within the estimated uncertainties and both agree with TT(BIPM17), a post-corrected time-scale produced by the Bureau International des Poids et Mesures (BIPM). We show that both methods could detect significant errors in TT(BIPM17) if they were present. We estimate the stability of the atomic clocks from which TT(BIPM17) is derived using observations of four rubidium fountain clocks at the US Naval Observatory. Comparing the power spectrum of TT(IPTA16) with that of these fountain clocks suggests that pulsar-based time-scales are unlikely to contribute to the stability of the best time-scales over the next decade, but they will remain a valuable independent check on atomic time-scales. We also find that the stability of the pulsar-based time-scale is likely to be limited by our knowledge of solar-system dynamics, and that errors in TT(BIPM17) will not be a limiting factor for the primary goal of the IPTA, which is to search for the signatures of nano-Hertz gravitational waves.
Published: 2019
Full Text: View/download PDF

10. The International Pulsar Timing Array: Second Data Release

Author: B B P Perara, M E DeCesar, P B Demorest, M Kerr, L Lentati, D J Nice, S Oslowski, S M Ransom, M J Keith, Z Arzoumanian, M Bailes, P T Baker, C G Bassa, NDR Bhat, A Brazier, M Burgay, S Burke-Spolaor, R N Caballero, D J Champion, S Chatterjee, S Chen, I Cognard, J M Cordes, K Crowter, S Dai, G Desvignes, T Dolch, R D Ferdman, E C Ferrara, E Fonseca, J M Goldstein, E Graikou, L Guillemot, J S Hazboun, G Hobbs, H Hu, K Islo, G H Janssen, R Karuppusam, M Kramer, M T Lam, K J Lee, K Liu, J Luo, A G Lyne, R N Manchester, J W McKee, M A McLaughlin, C M F Mingarelli, A P Parthasarathy, T T Pennucci, D Perrodin, A Possenti, D J Reardon, C J Russell, S A Sanidas, A Sesana, G Shaifullah, R M Shannon, X Siemens, J Simon, R Spiewak, I H Stairs, B W Stappers, J K Swiggum, S R Taylor, G Theureau, C Tiburzi, M Vallisneri, A Vecchio, J B Wang, S B Zhang, L Zhang, W W Zhu, and X J Zhu
Subjects: Astronomy
Abstract: In this paper, we describe the International Pulsar Timing Array second data release, which includes recent pulsar timing data obtained by three regional consortia: the European Pulsar Timing Array, the North American Nanohertz Observatory for Gravitational Waves, and the Parkes Pulsar Timing Array. We analyse and where possible combine high-precision timing data for 65 millisecond pulsars which are regularly observed by these groups. A basic noise analysis, including the processes which are both correlated and uncorrelated in time, provides noise models and timing ephemerides for the pulsars. We find that the timing precisions of pulsars are generally improved compared to the previous data release, mainly due to the addition of new data in the combination. The main purpose of this work is to create the most up-to-date IPTA data release. These data are publicly available for searches for low-frequency gravitational waves and other pulsar science.
Published: 2019
Full Text: View/download PDF

11. CHIME Discovery of a Binary Pulsar with a Massive Non-Degenerate Companion

Author: Bridget C. Andersen, Emmanuel Fonseca, J. W. McKee, B. W. Meyers, Jing Luo, C. M. Tan, I. H. Stairs, Victoria M. Kaspi, M. H. van Kerkwijk, Mohit Bhardwaj, P. J. Boyle, Kathryn Crowter, Paul B. Demorest, Fengqiu A. Dong, Deborah C. Good, Jane F. Kaczmarek, Calvin Leung, Kiyoshi W. Masui, Arun Naidu, Cherry Ng, Chitrang Patel, Aaron B. Pearlman, Ziggy Pleunis, Masoud Rafiei-Ravandi, Mubdi Rahman, Scott M. Ransom, Kendrick M. Smith, and Shriharsh P. Tendulkar
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Of the more than $3{,}000$ radio pulsars currently known, only ${\sim}300$ are in binary systems, and only five of these consist of young pulsars with massive non-degenerate companions. We present the discovery and initial timing, accomplished using the Canadian Hydrogen Intensity Mapping Experiment telescope (CHIME), of the sixth such binary pulsar, PSR J2108+4516, a $0.577$-s radio pulsar in a 269-day orbit of eccentricity 0.09 with a companion of minimum mass $11$ M$_{\odot}$. Notably, the pulsar undergoes periods of substantial eclipse, disappearing from the CHIME $400{-}800$ MHz observing band for a large fraction of its orbit, and displays significant dispersion measure and scattering variations throughout its orbit, pointing to the possibility of a circumstellar disk or very dense stellar wind associated with the companion star. Subarcsecond resolution imaging with the Karl G. Jansky Very Large Array unambiguously demonstrates that the companion is a bright, $V \simeq 11$ OBe star, EM* UHA 138, located at a distance of $3.26(14)$ kpc. Archival optical observations of \companion{} approximately suggest a companion mass ranging from $17.5$ M$_{\odot} < M_{\rm c} < 23$ M$_{\odot}$, in turn constraining the orbital inclination angle to $50.3^{\circ} \lesssim i \lesssim 58.3^{\circ}$. With further multi-wavelength followup, PSR J2108+4516 promises to serve as another rare laboratory for the exploration of companion winds, circumstellar disks, and short-term evolution through extended-body orbital dynamics., 20 pages, 12 figures, accepted by ApJ
Published: 2022

12. Robust parameter estimation from pulsar timing data

Author: Samajdar, A, Shaifullah, G, Sesana, A, Antoniadis, J, Burgay, M, Chen, S, Cognard, I, Guillemot, L, Kramer, M, W McKee, J, B Mickaliger, M, Theureau, G, Van&nbsp, E, Wateren, D, A Samajdar, G Shaifullah, A Sesana, J Antoniadis, M Burgay, S Chen, I Cognard, L Guillemot, M Kramer, J W McKee, M B Mickaliger, G Theureau, E Van&nbsp, der Wateren, Samajdar, A, Shaifullah, G, Sesana, A, Antoniadis, J, Burgay, M, Chen, S, Cognard, I, Guillemot, L, Kramer, M, W McKee, J, B Mickaliger, M, Theureau, G, Van&nbsp, E, Wateren, D, A Samajdar, G Shaifullah, A Sesana, J Antoniadis, M Burgay, S Chen, I Cognard, L Guillemot, M Kramer, J W McKee, M B Mickaliger, G Theureau, E Van&nbsp, and der Wateren
Abstract: Recently, global pulsar timing arrays have released results from searching for a nano-Hertz gravitational wave background signal. Although there has not been any definite evidence of the presence of such a signal in residuals of pulsar timing data yet, with more and improved data in future, a statistically significant detection is expected to be made. Stochastic algorithms are used to sample a very large parameter space to infer results from data. In this paper, we attempt to rule out effects arising from the stochasticity of the sampler in the inference process. We compare different configurations of nested samplers and the more commonly used markov chain monte carlo method to sample the pulsar timing array parameter space and account for times taken by the different samplers on same data. Although we obtain consistent results on parameters from different sampling algorithms, we propose two different samplers for robustness checks on data in the future to account for cross-checks between sampling methods as well as realistic run-times.
Published: 2022

13. Dual-frequency single-pulse study of PSR B0950+08

Author: A. V. Bilous, J. M. Grießmeier, T. Pennucci, Z. Wu, L. Bondonneau, V. Kondratiev, J. van Leeuwen, Y. Maan, L. Connor, L. C. Oostrum, E. Petroff, J. P. W. Verbiest, D. Vohl, J. W. McKee, G. Shaifullah, G. Theureau, O. M. Ulyanov, B. Cecconi, A. H. Coolen, S. Corbel, S. Damstra, H. Dénes, J. N. Girard, B. Hut, M. Ivashina, O. O. Konovalenko, A. Kutkin, G. M. Loose, H. Mulder, M. Ruiter, R. Smits, P. L. Tokarsky, N. J. Vermaas, V. V. Zakharenko, P. Zarka, J. Ziemke, High Energy Astrophys. & Astropart. Phys (API, FNWI), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Bilous, A, Griessmeier, J, Pennucci, T, Wu, Z, Bondonneau, L, Kondratiev, V, van Leeuwen, J, Maan, Y, Connor, L, Oostrum, L, Petroff, E, Verbiest, J, Vohl, D, Mckee, J, Shaifullah, G, Theureau, G, Ulyanov, O, Cecconi, B, Coolen, A, Corbel, S, Damstra, S, Denes, H, Girard, J, Hut, B, Ivashina, M, Konovalenko, O, Kutkin, A, Loose, G, Mulder, H, Ruiter, M, Smits, R, Tokarsky, P, Vermaas, N, Zakharenko, V, Zarka, P, and Ziemke, J
Subjects: Astrophysics::High Energy Astrophysical Phenomena, Population, Frequency drift, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Spectral line, Radio telescope, stars: neutron, Pulsar, 0103 physical sciences, education, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, education.field_of_study, Scintillation, Line-of-sight, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, Interstellar medium, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: PSR B0950+08 is a bright non-recycled pulsar whose single-pulse fluence variability is reportedly large. Based on observations at two widely separated frequencies, 55 MHz (NenuFAR) and 1.4 GHz (Westerbork Synthesis Radio Telescope), we review the properties of these single pulses. We conclude that they are more similar to ordinary pulses of radio emission than to a special kind of short and bright Giant Pulses, observed from only a handful of pulsars. We argue that temporal variation of properties of interstellar medium along the line of sight to this nearby pulsar, namely the fluctuating size of decorrelation bandwidth of diffractive scintillation makes important contribution to observed single-pulse fluence variability. We further present interesting structures in the low-frequency single-pulse spectra that resemble the "sad trombones" seen in Fast Radio Bursts (FRBs); although for PSR B0950+08 the upward frequency drift is also routinely present. We explain these spectral features with radius-to-frequency mapping, similar to the model developed by Wang et al. (2019) for FRBs. Finally, we speculate that microsecond-scale fluence variability of the general pulsar population remains poorly known, and that its further study may bring important clues about the nature of FRBs., Accepted by A&A. This version includes a number of minor corrections, including corrected FRB luminosities on the time-luminosity phase-space plot for radio pulses from neutron stars and repeating FRBs
Published: 2022
Full Text: View/download PDF

14. Localizing FRBs through VLBI with the Algonquin Radio Observatory 10 m Telescope

Author: T. Cassanelli, Calvin Leung, M. Rahman, K. Vanderlinde, J. Mena-Parra, S. Cary, Kiyoshi W. Masui, Jing Luo, H.-H. Lin, A. Bij, A. Gill, D. Baker, Kevin Bandura, S. Berger, P. J. Boyle, Charanjot Brar, S. Chatterjee, D. Cubranic, Matt Dobbs, E. Fonseca, D. C. Good, J. F. Kaczmarek, V. M. Kaspi, T. L. Landecker, A. E. Lanman, Dongzi Li, J. W. McKee, B. W. Meyers, D. Michilli, Arun Naidu, Cherry Ng, Chitrang Patel, Aaron B. Pearlman, U. L. Pen, Ziggy Pleunis, Brendan Quine, A. Renard, Pranav Sanghavi, K. M. Smith, Ingrid Stairs, and Shriharsh P. Tendulkar
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Space and Planetary Science, 0103 physical sciences, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, 01 natural sciences
Abstract: The CHIME/FRB experiment has detected thousands of Fast Radio Bursts (FRBs) due to its sensitivity and wide field of view; however, its low angular resolution prevents it from localizing events to their host galaxies. Very Long Baseline Interferometry (VLBI), triggered by FRB detections from CHIME/FRB will solve the challenge of localization for non-repeating events. Using a refurbished 10-m radio dish at the Algonquin Radio Observatory located in Ontario Canada, we developed a testbed for a VLBI experiment with a theoretical ~, Accepted for publication by AJ
Published: 2022

15. Study of 72 pulsars discovered in the PALFA survey: Timing analysis, glitch activity, emission variability, and a pulsar in an eccentric binary

Author: E. Parent, H. Sewalls, P. C. C. Freire, T. Matheny, A. G. Lyne, B. B. P. Perera, F. Cardoso, M. A. McLaughlin, B. Allen, A. Brazier, F. Camilo, S. Chatterjee, J. M. Cordes, F. Crawford, J. S. Deneva, F. A. Dong, R. D. Ferdman, E. Fonseca, J. W. T. Hessels, V. M. Kaspi, B. Knispel, J. van Leeuwen, R. S. Lynch, B. M. Meyers, J. W. McKee, M. B. Mickaliger, C. Patel, S. M. Ransom, A. Rochon, P. Scholz, I. H. Stairs, B. W. Stappers, C. M. Tan, W. W. Zhu, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Space and Planetary Science, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics
Abstract: We present new discoveries and results from long-term timing of 72 pulsars discovered in the Arecibo PALFA survey, including precise determination of astrometric and spin parameters, and flux density and scatter broadening measurements at 1.4 GHz. Notable discoveries include two young pulsars (characteristic ages $\sim$30 kyr) with no apparent supernova remnant associations, three mode changing, 12 nulling and two intermittent pulsars. We detected eight glitches in five pulsars. Among them is PSR J1939+2609, an apparently old pulsar (characteristic age $\sim$1 Gy), and PSR J1954+2529, which likely belongs to a newly-emerging class of binary pulsars. The latter is the only pulsar among the 72 that is clearly not isolated: a non-recycled neutron star with a 931-ms spin period in an eccentric ($e\,=\,0.114$) wide ($P_b\,=\,82.7\,$d) orbit with a companion of undetermined nature having a minimum mass of $\sim0.6\,M_{\odot}$. Since operations at Arecibo ceased in 2020 August, we give a final tally of PALFA sky coverage, and compare its 207 pulsar discoveries to the known population. On average, they are 50% more distant than other Galactic plane radio pulsars; PALFA millisecond pulsars (MSP) have twice the dispersion measure per unit spin period than the known population of MSP in the Plane. The four intermittent pulsars discovered by PALFA more than double the population of such objects, which should help to improve our understanding of pulsar magnetosphere physics. The statistics for these, RRATS, and nulling pulsars suggest that there are many more of these objects in the Galaxy than was previously thought., 39 pages, 18 figures, 9 tables. Accepted for publication in ApJ
Published: 2022

16. Removal and replacement of interference in tied-array radio pulsar observations using the spectral kurtosis estimator

Author: S. Sanidas, Kejia Lee, C. G. Bassa, Ramesh Karuppusamy, Ismaël Cognard, M. B. Purver, D. Perrodin, K. Liu, Michael Kramer, Gemma H. Janssen, J. W. McKee, Benjamin Stappers, R. Smits, ITA, GBR, FRA, DEU, CAN, NLD, and CHN
Subjects: Gaussian, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Interference (wave propagation), 01 natural sciences, law.invention, Telescope, 010104 statistics & probability, symbols.namesake, Pulsar, law, 0103 physical sciences, 0101 mathematics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Statistical hypothesis testing, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Estimator, Astronomy and Astrophysics, Computational physics, Amplitude, Space and Planetary Science, Kurtosis, symbols, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We describe how to implement the spectral kurtosis method of interference removal (zapping) on a digitized signal of averaged power values. Spectral kurtosis is a hypothesis test, analogous to the t-test, with a null hypothesis that the amplitudes from which power is formed belong to a `good' distribution -- typically Gaussian with zero mean -- where power values are zapped if the hypothesis is rejected at a specified confidence level. We derive signal-to-noise ratios (SNRs) as a function of amount of zapping for folded radio pulsar observations consisting of a sum of signals from multiple telescopes in independent radio-frequency interference (RFI) environments, comparing four methods to compensate for lost data with coherent (tied-array) and incoherent summation. For coherently summed amplitudes, scaling amplitudes from non-zapped telescopes achieves a higher SNR than replacing zapped amplitudes with artificial noise. For incoherently summed power values, the highest SNR is given by scaling power from non-zapped telescopes to maintain a constant mean. We use spectral kurtosis to clean a tied-array radio pulsar observation by the Large European Array for Pulsars (LEAP): the signal from one telescope is zapped with time and frequency resolutions of 6.25 $\mu$s and 0.16 MHz, removing interference along with 0.27 per cent of `good' data, giving an uncertainty of 0.25 $\mu$s in pulse time of arrival (TOA) for PSR J1022+1001. We use a single-telescope observation to demonstrate recovery of the pulse profile shape, with 0.6 per cent of data zapped and a reduction from 1.22 to 0.70 $\mu$s in TOA uncertainty., Comment: 16 pages, 9 figures
Published: 2022

17. The International Pulsar Timing Array second data release: Search for an isotropic gravitational wave background

Author: J Antoniadis, Z Arzoumanian, S Babak, M Bailes, A-S Bak Nielsen, P T Baker, C G Bassa, B Bécsy, A Berthereau, M Bonetti, A Brazier, P R Brook, M Burgay, S Burke-Spolaor, R N Caballero, J A Casey-Clyde, A Chalumeau, D J Champion, M Charisi, S Chatterjee, S Chen, I Cognard, J M Cordes, N J Cornish, F Crawford, H T Cromartie, K Crowter, S Dai, M E DeCesar, P B Demorest, G Desvignes, T Dolch, B Drachler, M Falxa, E C Ferrara, W Fiore, E Fonseca, J R Gair, N Garver-Daniels, B Goncharov, D C Good, E Graikou, L Guillemot, Y J Guo, J S Hazboun, G Hobbs, H Hu, K Islo, G H Janssen, R J Jennings, A D Johnson, M L Jones, A R Kaiser, D L Kaplan, R Karuppusamy, M J Keith, L Z Kelley, M Kerr, J S Key, M Kramer, M T Lam, W G Lamb, T J W Lazio, K J Lee, L Lentati, K Liu, J Luo, R S Lynch, A G Lyne, D R Madison, R A Main, R N Manchester, A McEwen, J W McKee, M A McLaughlin, M B Mickaliger, C M F Mingarelli, C Ng, D J Nice, S Osłowski, A Parthasarathy, T T Pennucci, B B P Perera, D Perrodin, A Petiteau, N S Pol, N K Porayko, A Possenti, S M Ransom, P S Ray, D J Reardon, C J Russell, A Samajdar, L M Sampson, S Sanidas, J M Sarkissian, K Schmitz, L Schult, A Sesana, G Shaifullah, R M Shannon, B J Shapiro-Albert, X Siemens, J Simon, T L Smith, L Speri, R Spiewak, I H Stairs, B W Stappers, D R Stinebring, J K Swiggum, S R Taylor, G Theureau, C Tiburzi, M Vallisneri, E van der Wateren, A Vecchio, J P W Verbiest, S J Vigeland, H Wahl, J B Wang, J Wang, L Wang, C A Witt, S Zhang, X J Zhu, Antoniadis, J, Arzoumanian, Z, Babak, S, Bailes, M, Bak Nielsen, A, Baker, P, Bassa, C, Becsy, B, Berthereau, A, Bonetti, M, Brazier, A, Brook, P, Burgay, M, Burke-Spolaor, S, Caballero, R, Casey-Clyde, J, Chalumeau, A, Champion, D, Charisi, M, Chatterjee, S, Chen, S, Cognard, I, Cordes, J, Cornish, N, Crawford, F, Cromartie, H, Crowter, K, Dai, S, Decesar, M, Demorest, P, Desvignes, G, Dolch, T, Drachler, B, Falxa, M, Ferrara, E, Fiore, W, Fonseca, E, Gair, J, Garver-Daniels, N, Goncharov, B, Good, D, Graikou, E, Guillemot, L, Guo, Y, Hazboun, J, Hobbs, G, Hu, H, Islo, K, Janssen, G, Jennings, R, Johnson, A, Jones, M, Kaiser, A, Kaplan, D, Karuppusamy, R, Keith, M, Kelley, L, Kerr, M, Key, J, Kramer, M, Lam, M, Lamb, W, Lazio, T, Lee, K, Lentati, L, Liu, K, Luo, J, Lynch, R, Lyne, A, Madison, D, Main, R, Manchester, R, Mcewen, A, Mckee, J, Mclaughlin, M, Mickaliger, M, Mingarelli, C, Ng, C, Nice, D, Oslowski, S, Parthasarathy, A, Pennucci, T, Perera, B, Perrodin, D, Petiteau, A, Pol, N, Porayko, N, Possenti, A, Ransom, S, Ray, P, Reardon, D, Russell, C, Samajdar, A, Sampson, L, Sanidas, S, Sarkissian, J, Schmitz, K, Schult, L, Sesana, A, Shaifullah, G, Shannon, R, Shapiro-Albert, B, Siemens, X, Simon, J, Smith, T, Speri, L, Spiewak, R, Stairs, I, Stappers, B, Stinebring, D, Swiggum, J, Taylor, S, Theureau, G, Tiburzi, C, Vallisneri, M, Van Der Wateren, E, Vecchio, A, Verbiest, J, Vigeland, S, Wahl, H, Wang, J, Wang, L, Witt, C, Zhang, S, Zhu, X, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire Univers et Théories (LUTH (UMR_8102)), ANR-18-CE31-0015,PTA-France,Recherche d'ondes gravitationnelles avec un réseau de pulsars en France(2018), ITA, USA, GBR, FRA, DEU, AUS, CAN, GRC, NLD, CHN, RUS, CHE, and HUN
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, [PHYS]Physics [physics], Astrophysics and Astronomy, Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, methods: Data analysi, pulsars: General, methods: data analysis, gravitational waves, Space and Planetary Science, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), gravitational wave, astro-ph.IM
Abstract: We searched for an isotropic stochastic gravitational wave background in the second data release of the International Pulsar Timing Array, a global collaboration synthesizing decadal-length pulsar-timing campaigns in North America, Europe, and Australia. In our reference search for a power law strain spectrum of the form $h_c = A(f/1\,\mathrm{yr}^{-1})^{\alpha}$, we found strong evidence for a spectrally-similar low-frequency stochastic process of amplitude $A = 3.8^{+6.3}_{-2.5}\times10^{-15}$ and spectral index $\alpha = -0.5 \pm 0.5$, where the uncertainties represent 95\% credible regions, using information from the auto- and cross-correlation terms between the pulsars in the array. For a spectral index of $\alpha = -2/3$, as expected from a population of inspiralling supermassive black hole binaries, the recovered amplitude is $A = 2.8^{+1.2}_{-0.8}\times10^{-15}$. Nonetheless, no significant evidence of the Hellings-Downs correlations that would indicate a gravitational-wave origin was found. We also analyzed the constituent data from the individual pulsar timing arrays in a consistent way, and clearly demonstrate that the combined international data set is more sensitive. Furthermore, we demonstrate that this combined data set produces comparable constraints to recent single-array data sets which have more data than the constituent parts of the combination. Future international data releases will deliver increased sensitivity to gravitational wave radiation, and significantly increase the detection probability., 17 pages, 12 figures, accepted in MNRAS
Published: 2022
Full Text: View/download PDF

18. Robust parameter estimation from pulsar timing data

Author: A Samajdar, G Shaifullah, A Sesana, J Antoniadis, M Burgay, S Chen, I Cognard, L Guillemot, M Kramer, J W McKee, M B Mickaliger, G Theureau, E Van&nbsp, derundefined Wateren, Samajdar, A, Shaifullah, G, Sesana, A, Antoniadis, J, Burgay, M, Chen, S, Cognard, I, Guillemot, L, Kramer, M, W McKee, J, B Mickaliger, M, Theureau, G, Van&nbsp, E, and Wateren, D
Subjects: Space and Planetary Science, pulsars: general, Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, General Relativity and Quantum Cosmology (gr-qc), gravitational wave, methods: data analysi, General Relativity and Quantum Cosmology
Abstract: Recently, global pulsar timing arrays have released results from searching for a nano-Hertz gravitational wave background signal. Although there has not been any definite evidence of the presence of such a signal in residuals of pulsar timing data yet, with more and improved data in future, a statistically significant detection is expected to be made. Stochastic algorithms are used to sample a very large parameter space to infer results from data. In this paper, we attempt to rule out effects arising from the stochasticity of the sampler in the inference process. We compare different configurations of nested samplers and the more commonly used markov chain monte carlo method to sample the pulsar timing array parameter space and account for times taken by the different samplers on same data. Although we obtain consistent results on parameters from different sampling algorithms, we propose two different samplers for robustness checks on data in the future to account for cross-checks between sampling methods as well as realistic run-times., Comment: 8 pages, 5 figures, 4 tables
Published: 2022

19. Modelling annual scintillation arc variations in PSR J1643-1224 using the Large European Array for Pulsars

Author: G Mall, R A Main, J Antoniadis, C G Bassa, M Burgay, S Chen, I Cognard, R Concu, A Corongiu, M Gaikwad, H Hu, G H Janssen, R Karuppusamy, M Kramer, K J Lee, K Liu, J W McKee, A Melis, M B Mickaliger, D Perrodin, M Pilia, A Possenti, D J Reardon, S A Sanidas, T Sprenger, B W Stappers, L Wang, O Wucknitz, W W Zhu, ITA, GBR, FRA, DEU, AUS, CAN, GRC, NLD, and CHN
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Space and Planetary Science, Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: In this work we study variations in the parabolic scintillation arcs of the binary millisecond pulsar PSR J1643-1224 over five years using the Large European Array for Pulsars (LEAP). The 2D power spectrum of scintillation, called the secondary spectrum, often shows a parabolic distribution of power, where the arc curvature encodes the relative velocities and distances of the pulsar, ionised interstellar medium (IISM), and Earth. We observe a clear parabolic scintillation arc which varies in curvature throughout the year. The distribution of power in the secondary spectra are inconsistent with a single scattering screen which is fully 1D, or entirely isotropic. We fit the observed arc curvature variations with two models; an isotropic scattering screen, and a model with two independent 1D screens. We measure the distance to the scattering screen to be in the range 114-223 pc, depending on the model, consistent with the known distance of the foreground large-diameter HII region Sh 2-27 (112+/-17 pc), suggesting that it is the dominant source of scattering. We obtain only weak constraints on the pulsar's orbital inclination and angle of periastron, since the scintillation pattern is not very sensitive to the pulsar's motion, since the screen is much closer to the Earth than the pulsar. More measurements of this kind - where scattering screens can be associated with foreground objects - will help to inform the origins and distribution of scattering screens within our galaxy., 11 pages, 6 figures. Accepted by MNRAS
Published: 2022

20. Refined Mass and Geometric Measurements of the High-mass PSR J0740+6620

Author: Shriharsh P. Tendulkar, Deborah C. Good, V. M. Kaspi, J. W. McKee, Wenbai Zhu, Cherry Ng, Ross J. Jennings, Harsha Blumer, Fengqiu Adam Dong, D. R. Lorimer, Paul S. Ray, A. Naidu, E. C. Ferrara, H. A. Radovan, I. H. Stairs, Paul Demorest, William Fiore, Paul R. Brook, Zaven Arzoumanian, Paul T. Baker, Joseph K. Swiggum, C. M. Tan, Michael T. Lam, Timothy T. Pennucci, N. Garver-Daniels, Timothy Dolch, Natasha McMann, Alexander McEwen, B. W. Meyers, David J. Nice, M. A. McLaughlin, Brent J. Shapiro-Albert, Ismaël Cognard, J. Luo, Haley M. Wahl, L. Guillemot, A. Yu. Kirichenko, Aditya Parthasarathy, Matthew Kerr, Nihan Pol, M. L. Jones, Scott M. Ransom, Emmanuel Fonseca, H. T. Cromartie, M. E. DeCesar, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, General relativity, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Neutron star, Pulsar, Space and Planetary Science, [SDU]Sciences of the Universe [physics], 0103 physical sciences, High mass, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics
Abstract: We report results from continued timing observations of PSR J0740+6620, a high-mass, 2.8-ms radio pulsar in orbit with a likely ultra-cool white dwarf companion. Our data set consists of combined pulse arrival-time measurements made with the 100-m Green Bank Telescope and the Canadian Hydrogen Intensity Mapping Experiment telescope. We explore the significance of timing-based phenomena arising from general-relativistic dynamics and variations in pulse dispersion. When using various statistical methods, we find that combining $\sim 1.5$ years of additional, high-cadence timing data with previous measurements confirms and improves upon previous estimates of relativistic effects within the PSR J0740+6620 system, with the pulsar mass $m_{\rm p} = 2.08^{+0.07}_{-0.07}$ M$_\odot$ (68.3\% credibility) determined by the relativistic Shapiro time delay. For the first time, we measure secular variation in the orbital period and argue that this effect arises from apparent acceleration due to significant transverse motion. After incorporating contributions from Galactic differential rotation and off-plane acceleration in the Galactic potential, we obtain a model-dependent distance of $d = 1.14^{+0.17}_{-0.15}$ kpc (68.3\% credibility). This improved distance confirms the ultra-cool nature of the white dwarf companion determined from recent optical observations. We discuss the prospects for future observations with next-generation facilities, which will likely improve the precision on $m_{\rm p}$ for J0740+6620 by an order of magnitude within the next few years., Final version after minor corrections during referee process. Published in the Astrophysical Journal Letters on 1 July 2021
Published: 2021
Full Text: View/download PDF

21. Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: inferences in the stochastic gravitational-wave background search

Author: Cees Bassa, J. W. McKee, A.-S. Bak Nielsen, E. van der Wateren, J. Wang, Antoine Petiteau, Andrea Possenti, Mitchell B. Mickaliger, Alberto Sesana, Kejia Lee, Delphine Perrodin, E. Graikou, Lan Wang, A. Chalumeau, R. N. Caballero, Kang Liu, Caterina Tiburzi, N. K. Porayko, Siyuan Chen, H. Xu, Alberto Vecchio, H. Hu, M. Falxa, Gemma H. Janssen, X. J. Liu, Ramesh Karuppusamy, John Antoniadis, David Champion, Ismaël Cognard, Michael Kramer, Benetge Perera, Gregory Desvignes, Stanislav Babak, Aditya Parthasarathy, Gilles Theureau, Y J Guo, L. Speri, Lucas Guillemot, Robert D. Ferdman, S. A. Sanidas, Paulo C. C. Freire, Michael Keith, Ben Stappers, J. Jang, Jonathan R. Gair, A. Berthereau, Andrew Lyne, G. Shaifullah, A. Samajdar, R. A. Main, M. Burgay, Joris P. W. Verbiest, RUS, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), ANR-18-CE31-0015,PTA-France,Recherche d'ondes gravitationnelles avec un réseau de pulsars en France(2018), Chen, S, Caballero, R, Guo, Y, Chalumeau, A, Liu, K, Shaifullah, G, Lee, K, Babak, S, Desvignes, G, Parthasarathy, A, Hu, H, Van Der Wateren, E, Antoniadis, J, Bak Nielsen, A, Bassa, C, Berthereau, A, Burgay, M, Champion, D, Cognard, I, Falxa, M, Ferdman, R, Freire, P, Gair, J, Graikou, E, Guillemot, L, Jang, J, Janssen, G, Karuppusamy, R, Keith, M, Kramer, M, Liu, X, Lyne, A, Main, R, Mckee, J, Mickaliger, M, Perera, B, Perrodin, D, Petiteau, A, Porayko, N, Possenti, A, Samajdar, A, Sanidas, S, Sesana, A, Speri, L, Stappers, B, Theureau, G, Tiburzi, C, Vecchio, A, Verbiest, J, Wang, J, Wang, L, and Xu, H
Subjects: Spatial correlation, General relativity, Astronomy, Astrophysics, 01 natural sciences, Gravitational wave background, Pulsar, Millisecond pulsar, pulsars: general, 0103 physical sciences, gravitational wave, 010303 astronomy & astrophysics, Physics, Spectral index, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, methods: data analysis, European Pulsar Timing Array, Amplitude, gravitational waves, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics - High Energy Astrophysical Phenomena, methods: data analysi, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present results from the search for a stochastic gravitational-wave background (GWB) as predicted by the theory of General Relativity using six radio millisecond pulsars from the Data Release 2 (DR2) of the European Pulsar Timing Array (EPTA) covering a timespan up to 24 years. A GWB manifests itself as a long-term low-frequency stochastic signal common to all pulsars, a common red signal (CRS), with the characteristic Hellings-Downs (HD) spatial correlation. Our analysis is performed with two independent pipelines, \eprise{} and \tn{}+\ftwo{}, which produce consistent results. A search for a CRS with simultaneous estimation of its spatial correlations yields spectral properties compatible with theoretical GWB predictions, but does not result in the required measurement of the HD correlation, as required for GWB detection. Further Bayesian model comparison between different types of CRSs, including a GWB, finds the most favoured model to be the common uncorrelated red noise described by a power-law with $A = 5.13_{-2.73}^{+4.20} \times 10^{-15}$ and $\gamma = 3.78_{-0.59}^{+0.69}$ (95\% credible regions). Fixing the spectral index to $\gamma=13/3$ as expected from the GWB by circular, inspiralling supermassive black-hole binaries results in an amplitude of $A =2.95_{-0.72}^{+0.89} \times 10^{-15}$. We implement three different models, BAYESEPHEM, LINIMOSS and EPHEMGP, to address possible Solar-system ephemeris (SSE) systematics and conclude that our results may only marginally depend on these effects. This work builds on the methods and models from the studies on the EPTA DR1. We show that under the same analysis framework the results remain consistent after the data set extension., Comment: 25 pages, 10 figures, 7 tables, 2 appendix tables and 1 appendix figure
Published: 2021
Full Text: View/download PDF

22. Pulsars with NenuFAR: backend and pipelines

Author: Cyril Tasse, A. Possenti, Serge Yerin, Siyuan Chen, L. Bondonneau, C. Viou, M. Serylak, G. Shaifullah, Richard Dallier, J. W. McKee, Z. Wu, Julien N. Girard, Baptiste Cecconi, J.-M. Grießmeier, V. I. Kondratiev, M. Tagger, L. Guillemot, M. Brionne, Maura Pilia, R. A. Main, A. Loh, Ismaël Cognard, P. Zarka, Joris P. W. Verbiest, Caterina Tiburzi, Lilian Martin, Carine Briand, Stephane Corbel, A. V. Bilous, G. Theureau, Olaf Wucknitz, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Universität Bielefeld = Bielefeld University, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Rhodes University, Grahamstown, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Bondonneau, L, Griessmeier, J, Theureau, G, Cognard, I, Brionne, M, Kondratiev, V, Bilous, A, Mckee, J, Zarka, P, Viou, C, Guillemot, L, Chen, S, Main, R, Pilia, M, Possenti, A, Serylak, M, Shaifullah, G, Tiburzi, C, Verbiest, J, Wu, Z, Wucknitz, O, Yerin, S, Briand, C, Cecconi, B, Corbel, S, Dallier, R, Girard, J, Loh, A, Martin, L, Tagger, M, Tasse, C, Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)
Subjects: Physics - Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, 4/3, 01 natural sciences, frequency: high, Radio telescope, High Energy Physics - Phenomenology (hep-ph), Pulsar, Millisecond pulsar, Observatory, pulsars: general, 0103 physical sciences, site, Instrumentation (computer programming), structure, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), pulsar, Physics, radio wave, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Crab Pulsar, Astrophysics::Instrumentation and Methods for Astrophysics, resolution, Astronomy and Astrophysics, LOFAR, Instrumentation and Detectors (physics.ins-det), sensitivity, coherence, observatory, High Energy Physics - Phenomenology, frequency: low, Space and Planetary Science, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], dispersion, methods: observational, Astrophysics - Instrumentation and Methods for Astrophysics, performance, Radio wave
Abstract: NenuFAR (New extension in Nan\c{c}ay upgrading LoFAR) is a new radio telescope developed and built on the site of the Nan\c{c}ay Radio Observatory. It is designed to observe the largely unexplored frequency window from 10 to 85\,MHz, offering a high sensitivity across its full bandwidth. NenuFAR has started its "early science" operation in July 2019, with 58\% of its final collecting area being available. Pulsars are one of the major topics for the scientific exploitation of this frequency range and represent an important challenge in terms of instrumentation. Designing instrumentation at these frequencies is complicated by the need to compensate for the effects of both the interstellar medium and the ionosphere on the observed signal. Our real-time pipeline LUPPI (Low frequency Ultimate Pulsar Processing Instrumentation) is able to cope with a high data rate and to provide real-time coherent de-dispersion down to the lowest frequencies reached by NenuFAR (10\,MHz). The full backend functionality is described, as well as the main pulsar observing modes (folded, single-pulse, waveform, and dynamic spectrum). This instrumentation allowed us to detect 172 pulsars in our first targeted search below 85\,MHz, including 10 millisecond pulsars (6 of which detected for the first time below 100 MHz). We also present some of the "early science" results of NenuFAR on pulsars: a high frequency resolution mapping of PSR B1919$+$21's emission profile and a detailed observation of single-pulse sub-structures from PSR~B0809$+$74 down to 16\,MHz, the high rate of giant-pulse emission from the Crab pulsar detected at 68.7\,MHz (43 events/min), and the illustration of the very good timing performance of the instrumentation, allowing us to study dispersion measure variations in great detail., Comment: 13 pages, 14 figures, submitted to A&A
Published: 2020
Full Text: View/download PDF

23. The CHIME Pulsar Project: System Overview

Author: A. Renard, Paul Demorest, Laura Newburgh, B. W. Meyers, J. R. Shaw, A. E. Sikora, Ingrid H. Stairs, T. L. Landecker, M. A. Dobbs, Mandana Amiri, N. T. Denman, Scott M. Ransom, Calvin Leung, Jing Luo, A. Naidu, Cherry Ng, C. Brar, Victoria M. Kaspi, C. M. Tan, K. Vanderlinde, J. W. McKee, I. Tretyakov, H. Wang, Xin Wang, M. Fandino, C. Patel, Hsiu-Hsien Lin, F. Q. Dong, Alex S. Hill, Kiyoshi Masui, C. Höfer, Emmanuel Fonseca, J. F. Cliche, P. J. Boyle, Mark Halpern, Kevin Bandura, D. Cubranic, Daniele Michilli, J. Mena-Parra, Shriharsh P. Tendulkar, P. Scholz, Deborah C. Good, T. Pinsonneault-Marotte, and Kathryn Crowter
Subjects: astronomy data analysis, Physics, astronomical instrumentation, pulsar timing method, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, radio astronomy, 01 natural sciences, Astronomical instrumentation, Pulsar, Space and Planetary Science, 0103 physical sciences, astronomy data acquisition, Astrophysics - Instrumentation and Methods for Astrophysics, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), radio pulsars, Radio astronomy
Abstract: We present the design, implementation and performance of a digital backend constructed for the Canadian Hydrogen Intensity Mapping Experiment (CHIME) that uses accelerated computing to observe radio pulsars and transient radio sources. When operating, the CHIME correlator outputs 10 independent streams of beamformed data for the CHIME/Pulsar backend that digitally track specified celestial positions. Each of these independent streams are processed by the CHIME/Pulsar backend system which can coherently dedisperse, in real-time, up to dispersion measure values of 2500 pc/cm$^{-3}$ . The tracking beams and real-time analysis system are autonomously controlled by a priority-based algorithm that schedules both known sources and positions of interest for observation with observing cadences as small as one day. Given the distribution of known pulsars and radio-transient sources, the CHIME/Pulsar system can monitor up to 900 positions once per sidereal day and observe all sources with declinations greater than $-20^\circ$ once every $\sim$2 weeks. We also discuss the science program enabled through the current modes of data acquisition for CHIME/Pulsar that centers on timing and searching experiments., Comment: 18 pages, 9 figures, 1 table. Submitted to ApJS
Published: 2020
Full Text: View/download PDF

24. A pulsar-based time-scale from the International Pulsar Timing Array

Author: Sourav Chatterjee, Daniel J. Reardon, Ismaël Cognard, Gemma H. Janssen, Sarah Burke-Spolaor, Zaven Arzoumanian, Michael T. Lam, Kejia Lee, Michael Kramer, Benetge Perera, J. B. Wang, L. Guo, Renée Spiewak, Ryan Shannon, David J. Nice, Richard N. Manchester, N. D. R. Bhat, D. Matsakis, E. Graikou, Joseph Simon, Ingrid H. Stairs, R. N. Caballero, Shi Dai, Matthew Bailes, Christopher J. Russell, Alberto Sesana, Robert D. Ferdman, Lucas Guillemot, Delphine Perrodin, Xing-Jiang Zhu, Andrew Lyne, Chiara M. F. Mingarelli, C. G. Bassa, Benjamin Stappers, A. Brazier, R. van Haasteren, Timothy T. Pennucci, J. W. McKee, Yue-Fei Wang, Maura McLaughlin, Michael Keith, L. Toomey, Matthew Kerr, William A. Coles, Timothy Dolch, Stefan Oslowski, M. L. Tong, Stephen Taylor, D. J. Champion, Kang Liu, S. A. Sanidas, George Hobbs, J. K. Swiggum, Gregory Desvignes, Gilles Theureau, A. Possenti, T. J. W. Lazio, R. S. Lynch, G. Shaifullah, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Hobbs, G, Guo, L, Caballero, R, Coles, W, Lee, K, Manchester, R, Reardon, D, Matsakis, D, Tong, M, Arzoumanian, Z, Bailes, M, Bassa, C, Bhat, N, Brazier, A, Burke-Spolaor, S, Champion, D, Chatterjee, S, Cognard, I, Dai, S, Desvignes, G, Dolch, T, Ferdman, R, Graikou, E, Guillemot, L, Janssen, G, Keith, M, Kerr, M, Kramer, M, Lam, M, Liu, K, Lyne, A, Lazio, T, Lynch, R, Mckee, J, Mclaughlin, M, Mingarelli, C, Nice, D, Osłowski, S, Pennucci, T, Perera, B, Perrodin, D, Possenti, A, Russell, C, Sanidas, S, Sesana, A, Shaifullah, G, Shannon, R, Simon, J, Spiewak, R, Stairs, I, Stappers, B, Swiggum, J, Taylor, S, Theureau, G, Toomey, L, van Haasteren, R, Wang, J, Wang, Y, Zhu, X, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), ITA, USA, GBR, FRA, DEU, AUS, CAN, NLD, CHN, and HUN
Subjects: Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astronomy & Astrophysics, 01 natural sciences, Stability (probability), general [pulsars], Pulsar, Millisecond pulsar, Observatory, pulsars: general, 0103 physical sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, time, Physics, 010308 nuclear & particles physics, Gravitational wave, Spectral density, Astronomy and Astrophysics, Atomic clock, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics - Instrumentation and Methods for Astrophysics, Noise (radio), Astronomical and Space Sciences
Abstract: We have constructed a new timescale, TT(IPTA16), based on observations of radio pulsars presented in the first data release from the International Pulsar Timing Array (IPTA). We used two analysis techniques with independent estimates of the noise models for the pulsar observations and different algorithms for obtaining the pulsar timescale. The two analyses agree within the estimated uncertainties and both agree with TT(BIPM17), a post-corrected timescale produced by the Bureau International des Poids et Mesures (BIPM). We show that both methods could detect significant errors in TT(BIPM17) if they were present. We estimate the stability of the atomic clocks from which TT(BIPM17) is derived using observations of four rubidium fountain clocks at the US Naval Observatory. Comparing the power spectrum of TT(IPTA16) with that of these fountain clocks suggests that pulsar-based timescales are unlikely to contribute to the stability of the best timescales over the next decade, but they will remain a valuable independent check on atomic timescales. We also find that the stability of the pulsar-based timescale is likely to be limited by our knowledge of solar-system dynamics, and that errors in TT(BIPM17) will not be a limiting factor for the primary goal of the IPTA, which is to search for the signatures of nano-Hertz gravitational waves., Comment: accepted by MNRAS
Published: 2020
Full Text: View/download PDF

25. Dispersion measure variability for 36 millisecond pulsars at 150 MHz with LOFAR

Author: Rene P. Breton, C. Vocks, A. V. Bilous, Stefan Oslowski, J. Y. Donner, J. Künsemöller, Michael Kramer, A.-S. Bak Nielsen, Evan Keane, James M. Anderson, V. I. Kondratiev, M. Serylak, Caterina Tiburzi, B. Ciardi, O. Wucknitz, Marcus Brüggen, Charlotte Sobey, J. van Leeuwen, J. W. McKee, Joris P. W. Verbiest, Matthias Hoeft, J.-M. Grießmeier, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), CNRS-INSU, and European Project: 617199,EC:FP7:ERC,ERC-2013-CoG,ALERT(2014)
Subjects: ISM: structure, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, 01 natural sciences, law.invention, Telescope, Pulsar, Millisecond pulsar, law, pulsars: general, 0103 physical sciences, Dispersion (optics), 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [PHYS]Physics [physics], 010308 nuclear & particles physics, Gravitational wave, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, LOFAR, Astrophysics - Astrophysics of Galaxies, gravitational waves, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), ddc:520, Radio frequency, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Noise (radio)
Abstract: Radio pulses from pulsars are affected by plasma dispersion, which results in a frequency-dependent propagation delay. Variations in the magnitude of this effect lead to an additional source of red noise in pulsar timing experiments, including pulsar timing arrays that aim to detect nanohertz gravitational waves. We aim to quantify the time-variable dispersion with much improved precision and characterise the spectrum of these variations. We use the pulsar timing technique to obtain highly precise dispersion measure (DM) time series. Our dataset consists of observations of 36 millisecond pulsars, which were observed for up to 7.1 years with the LOFAR telescope at a centre frequency of ~150 MHz. Seventeen of these sources were observed with a weekly cadence, while the rest were observed at monthly cadence. We achieve a median DM precision of the order of 10^-5 cm^-3 pc for a significant fraction of our sources. We detect significant variations of the DM in all pulsars with a median DM uncertainty of less than 2x10^-4 cm^-3 pc. The noise contribution to pulsar timing experiments at higher frequencies is calculated to be at a level of 0.1-10 us at 1.4 GHz over a timespan of a few years, which is in many cases larger than the typical timing precision of 1 us or better that PTAs aim for. We found no evidence for a dependence of DM on radio frequency for any of the sources in our sample. The DM time series we obtained using LOFAR could in principle be used to correct higher-frequency data for the variations of the dispersive delay. However, there is currently the practical restriction that pulsars tend to provide either highly precise times of arrival (ToAs) at 1.4 GHz or a high DM precision at low frequencies, but not both, due to spectral properties. Combining the higher-frequency ToAs with those from LOFAR to measure the infinite-frequency ToA and DM would improve the result., Comment: 16 pages, 8 figures, 2 tables
Published: 2020
Full Text: View/download PDF

26. Measuring Interstellar Delays of PSR J0613-0200 over 7 years, using the Large European Array for Pulsars

Author: M. Gaikwad, Kejia Lee, S. Sanidas, C. G. Bassa, Siyuan Chen, John Antoniadis, Mitchell B. Mickaliger, Gemma H. Janssen, Weiwei Zhu, Benjamin Stappers, Long Wang, H. Hu, G. Mall, Delphine Perrodin, Olaf Wucknitz, Michael Kramer, Caterina Tiburzi, Ramesh Karuppusamy, Ismaël Cognard, R. A. Main, J. W. McKee, Kang Liu, Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), ITA, GBR, FRA, DEU, CAN, GRC, NLD, and CHN
Subjects: Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, 01 natural sciences, law.invention, Telescope, pulsars: individual: PSR J0613−0200, Pulsar, Millisecond pulsar, law, pulsars: general, 0103 physical sciences, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Scintillation, 010308 nuclear & particles physics, Scattering, Gravitational wave, Spectral density, Astronomy and Astrophysics, Pulse (physics), Space and Planetary Science, [SDU]Sciences of the Universe [physics], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena
Abstract: Using data from the Large European Array for Pulsars (LEAP), and the Effelsberg telescope, we study the scintillation parameters of the millisecond pulsar J0613-0200 over a 7 year timespan. The "secondary spectrum" -- the 2D power spectrum of scintillation -- presents the scattered power as a function of time delay, and contains the relative velocities of the pulsar, observer, and scattering material. We detect a persistent parabolic scintillation arc, suggesting scattering is dominated by a thin, anisotropic region. The scattering is poorly described by a simple exponential tail, with excess power at high delays; we measure significant, detectable scattered power at times out to $\sim 5 \mu s$, and measure the bulk scattering delay to be between 50 to 200\,ns with particularly strong scattering throughout 2013. These delays are too small to detect a change of the pulse profile shape, yet they would change the times-of-arrival as measured through pulsar timing. The arc curvature varies annually, and is well fit by a one-dimensional scattering screen $\sim 40\%$ of the way towards the pulsar, with a changing orientation during the increased scattering in 2013. Effects of uncorrected scattering will introduce time delays correlated over time in individual pulsars, and may need to be considered in gravitational wave analyses. Pulsar timing programs would benefit from simultaneously recording in a way that scintillation can be resolved, in order to monitor the variable time delays caused by multipath propagation., Comment: 12 pages, 10 figures. Published in MNRAS
Published: 2020
Full Text: View/download PDF

27. A precise mass measurement of PSR J2045 + 3633

Author: Benjamin Stappers, Michael Kramer, Lucas Guillemot, Michael Keith, Gilles Theureau, M. Berezina, Paulo C. C. Freire, Thomas M. Tauris, E. Graikou, Ismaël Cognard, D. J. Champion, Andrew Lyne, J. W. McKee, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)
Subjects: Proper motion, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Omega, general [pulsars], law.invention, Telescope, Radio telescope, stars: neutron, neutron [stars], Pulsar, law, stars: rotation, pulsars: general, 0103 physical sciences, pulsars: individual (PSR J2045 + 3633), Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [PHYS]Physics [physics], White dwarf, Astronomy and Astrophysics, Shapiro delay, Orientation (vector space), individual (PSR J2045 + 3633) [pulsars], Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], rotation [stars], Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We present the results of a timing analysis undertaken with the goal of obtaining an improved mass measurement of the recycled pulsar J2045+3633. Using regular high-cadence observations with the Effelsberg, Nan\c{c}ay, and Lovell radio telescopes, together with targeted campaigns with the Arecibo Telescope and Effelsberg, we have assembled a 6-yr timing data set for this pulsar. We measure highly significant values for the proper motion and the related rate of change of orbital semi-major axis ($\dot{x}$), and have obtained high precision values of the rate of advance of periastron time ($\dot{\omega}$), and two of the Shapiro delay parameters ($h_{3}$ and $\varsigma$). This has allowed us to improve the measurements of the pulsar and companion masses by an order of magnitude, yielding (with $1\sigma$ uncertainties) $1.251^{+0.021}_{-0.021}\,\text{M}_{\odot}$ for PSR J2045+3633, and $0.873^{+0.016}_{-0.014}\,\text{M}_{\odot}$ for its white dwarf companion, and has allowed us to place improved constraints on the geometrical orientation of the binary system. Using our measurements of the binary component masses and the orbital size, we consider possible evolutionary scenarios for the system., Comment: 17 pages, 6 figures, accepted for publication in MNRAS
Published: 2020
Full Text: View/download PDF

28. The International Pulsar Timing Array: Second data release

Author: Sarah Burke-Spolaor, Robert D. Ferdman, Stephen Taylor, Lei Zhang, Janna Goldstein, Caterina Tiburzi, Alberto Sesana, Ingrid H. Stairs, Elizabeth C. Ferrara, N. D. R. Bhat, Benetge Perera, Aditya Parthasarathy, Michael Kramer, H. Hu, Richard N. Manchester, Joseph Simon, L. Lentati, Matthew Kerr, Shi Dai, R. N. Caballero, Megan E. DeCesar, Paul Demorest, A. Possenti, Xing-Jiang Zhu, Kathryn Crowter, Weiwei Zhu, C. G. Bassa, Emmanuel Fonseca, Kejia Lee, Scott M. Ransom, Michael Keith, Stefan Oslowski, Chiara M. F. Mingarelli, D. J. Champion, Ramesh Karuppusamy, David J. Nice, Andrew Lyne, Timothy T. Pennucci, Timothy Dolch, J. K. Swiggum, Benjamin Stappers, K. Islo, Lucas Guillemot, Michele Vallisneri, J. B. Wang, X. Siemens, Gregory Desvignes, Gilles Theureau, James M. Cordes, Ismaël Cognard, Renée Spiewak, Siyuan Chen, Jing Luo, S. A. Sanidas, P. T. Baker, A. Brazier, Songbo Zhang, Alberto Vecchio, George Hobbs, Delphine Perrodin, Michael T. Lam, Jeffrey S. Hazboun, M. Burgay, Daniel J. Reardon, Zaven Arzoumanian, G. Shaifullah, J. W. McKee, Maura McLaughlin, Christopher J. Russell, Sourav Chatterjee, Kang Liu, Matthew Bailes, Gemma H. Janssen, Ryan Shannon, E. Graikou, Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Perera, B, Decesar, M, Demorest, P, Kerr, M, Lentati, L, Nice, D, Osłowski, S, Ransom, S, Keith, M, Arzoumanian, Z, Bailes, M, Baker, P, Bassa, C, Bhat, N, Brazier, A, Burgay, M, Burke-Spolaor, S, Caballero, R, Champion, D, Chatterjee, S, Chen, S, Cognard, I, Cordes, J, Crowter, K, Dai, S, Desvignes, G, Dolch, T, Ferdman, R, Ferrara, E, Fonseca, E, Goldstein, J, Graikou, E, Guillemot, L, Hazboun, J, Hobbs, G, Hu, H, Islo, K, Janssen, G, Karuppusamy, R, Kramer, M, Lam, M, Lee, K, Liu, K, Luo, J, Lyne, A, Manchester, R, Mckee, J, Mclaughlin, M, Mingarelli, C, Parthasarathy, A, Pennucci, T, Perrodin, D, Possenti, A, Reardon, D, Russell, C, Sanidas, S, Sesana, A, Shaifullah, G, Shannon, R, Siemens, X, Simon, J, Spiewak, R, Stairs, I, Stappers, B, Swiggum, J, Taylor, S, Theureau, G, Tiburzi, C, Vallisneri, M, Vecchio, A, Wang, J, Zhang, S, Zhang, L, Zhu, W, Zhu, X, Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Technologie de Belfort-Montbeliard (UTBM), PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Ephemeris, 01 natural sciences, Pulsar timing array, stars: neutron, neutron [stars], Pulsar, Millisecond pulsar, Observatory, pulsars: general, 0103 physical sciences, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Gravitational wave, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, methods: data analysis, European Pulsar Timing Array, gravitational waves, Space and Planetary Science, [SDU]Sciences of the Universe [physics], pulsars, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Noise (radio), Methods: data analysi
Abstract: In this paper, we describe the International Pulsar Timing Array second data release, which includes recent pulsar timing data obtained by three regional consortia: the European Pulsar Timing Array, the North American Nanohertz Observatory for Gravitational Waves, and the Parkes Pulsar Timing Array. We analyse and where possible combine high-precision timing data for 65 millisecond pulsars which are regularly observed by these groups. A basic noise analysis, including the processes which are both correlated and uncorrelated in time, provides noise models and timing ephemerides for the pulsars. We find that the timing precisions of pulsars are generally improved compared to the previous data release, mainly due to the addition of new data in the combination. The main purpose of this work is to create the most up-to-date IPTA data release. These data are publicly available for searches for low-frequency gravitational waves and other pulsar science., Comment: Submitted to MNRAS and in review, 23 pages, 5 figures
Published: 2019
Full Text: View/download PDF

29. Tests of gravitational symmetries with pulsar binary J1713+0747

Author: Michael Kramer, Kang Liu, Robert D. Ferdman, Lina Levin, P. Lazarus, Marjorie Gonzalez, Michael T. Lam, Gemma H. Janssen, Kejia Lee, Timothy Dolch, Norbert Wex, Scott M. Ransom, Kathryn Crowter, A. Jessner, Ramesh Karuppusamy, J. K. Swiggum, Andrew Lyne, K. Lazaridis, M. L. Jones, Gregory Desvignes, J. W. McKee, Gilles Theureau, Ismaël Cognard, R. Smits, Maura McLaughlin, A. Krieger, Weiwei Zhu, M. Burgay, D. J. Champion, Timothy T. Pennucci, Delphine Perrodin, Caterina Tiburzi, L. Lentati, Kevin Stovall, Joris P. W. Verbiest, A. Possenti, Christine Jordan, Glenn Jones, G. Shaifullah, E. Graikou, J. A. Ellis, David J. Nice, R. N. Caballero, Ingrid H. Stairs, Stefan Oslowski, Jason W. T. Hessels, C. G. Bassa, Emmanuel Fonseca, Benjamin Stappers, S. A. Sanidas, Zaven Arzoumanian, Lucas Guillemot, Paul Demorest, High Energy Astrophys. & Astropart. Phys (API, FNWI), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Centre National de la Recherche Scientifique ( CNRS ) -Université d'Orléans ( UO ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Unité Scientifique de la Station de Nançay ( USN ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Univers et Théories ( LUTH ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Zhu, W, Desvignes, G, Wex, N, Caballero, R, Champion, D, Demorest, P, Ellis, J, Janssen, G, Kramer, M, Krieger, A, Lentati, L, Nice, D, Ransom, S, Stairs, I, Stappers, B, Verbiest, J, Arzoumanian, Z, Bassa, C, Burgay, M, Cognard, I, Crowter, K, Dolch, T, Ferdman, R, Fonseca, E, Gonzalez, M, Graikou, E, Guillemot, L, Hessels, J, Jessner, A, Jones, G, Jones, M, Jordan, C, Karuppusamy, R, Lam, M, Lazaridis, K, Lazarus, P, Lee, K, Levin, L, Liu, K, Lyne, A, Mckee, J, Mclaughlin, M, Osłowski, S, Pennucci, T, Perrodin, D, Possenti, A, Sanidas, S, Shaifullah, G, Smits, R, Stovall, K, Swiggum, J, Theureau, G, Tiburzi, C, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: General relativity, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Astronomy, FOS: Physical sciences, Astrophysics, Lorentz covariance, 01 natural sciences, Binary pulsar, Gravitation, stars: neutron, General Relativity and Quantum Cosmology, Pulsar, Gravitational field, 0103 physical sciences, pulsars: individual (PSR J1713+0747), 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, Gravitational constant, European Pulsar Timing Array, binaries: general, Space and Planetary Science, [SDU]Sciences of the Universe [physics], gravitation, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Symmetries play an important role in modern theories of gravity. The strong equivalence principle (SEP) constitutes a collection of gravitational symmetries which are all implemented by general relativity. Alternative theories, however, are generally expected to violate some aspects of SEP. We test three aspects of SEP using observed change rates in the orbital period and eccentricity of binary pulsar J1713+0747: 1. the gravitational constant's constancy as part of locational invariance of gravitation; 2. the post-Newtonian parameter $\hat{\alpha}_3$ in gravitational Lorentz invariance; 3. the universality of free fall (UFF) for strongly self-gravitating bodies. Based on the pulsar timing result of the combined dataset from the North American Nanohertz Gravitational Observatory (NANOGrav) and the European Pulsar Timing Array (EPTA), we find $\dot{G}/G = (-0.1 \pm 0.9) \times 10^{-12}\,{\rm yr}^{-1}$, which is weaker than Solar system limits, but applies for strongly self-gravitating objects. Furthermore, we obtain the constraints $|\Delta|< 0.002$ for the UFF test and $-3\times10^{-20} < \hat{\alpha}_3 < 4\times10^{-20}$ at 95% confidence. These are the first direct UFF and $\hat{\alpha}_3$ tests based on pulsar binaries, and they overcome various limitations of previous tests., Comment: 11 pages, 6 figures, and 1 table; submitted to MNRAS
Published: 2019
Full Text: View/download PDF

30. A detailed study of giant pulses from PSR B1937+21 using the Large European Array for Pulsars

Author: Si Chen, Michael Kramer, J. W. McKee, Delphine Perrodin, Benjamin Stappers, M. Gaikwad, Gemma H. Janssen, Weiwei Zhu, C. G. Bassa, Kejia Lee, Long Wang, Kang Liu, S. A. Sanidas, Ramesh Karuppusamy, Ismaël Cognard, R. Smits, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), ITA, GBR, FRA, DEU, NLD, and CHN
Subjects: FOS: Physical sciences, Astrophysics, 01 natural sciences, Power law, stars: neutron, Time of arrival, Pulsar, Millisecond pulsar, stars: rotation, pulsars: general, 0103 physical sciences, structure, 010303 astronomy & astrophysics, pulsar, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, polarization, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, business.industry, Astronomy and Astrophysics, radiation mechanisms: non-thermal, Polarization (waves), Fractional polarization, Interstellar medium, modulation, pulsars: individual (PSR J1939+2134), Space and Planetary Science, [SDU]Sciences of the Universe [physics], correlation, fractional, Global Positioning System, pulsars: individual (PSR B1937+21), Astrophysics - High Energy Astrophysical Phenomena, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We have studied 4265 giant pulses (GPs) from the millisecond pulsar B1937+21; the largest-ever sample gathered for this pulsar, in observations made with the Large European Array for Pulsars. The pulse energy distribution of GPs associated with the interpulse are well-described by a power law, with index $\alpha = -3.99 \pm 0.04$, while those associated with the main pulse are best-described by a broken power law, with the break occurring at $\sim7$ Jy $\mu$s, with power law indices $\alpha_{\text{low}} = -3.48 \pm 0.04$ and $\alpha_{\text{high}} = -2.10 \pm 0.09$. The modulation indices of the GP emission are measured, which are found to vary by $\sim0.5$ at pulse phases close to the centre of the GP phase distributions. We find the frequency-resolved structure of GPs to vary significantly, and in a manner that cannot be attributed to the interstellar medium influence on the observed pulses. We examine the distribution of polarisation fractions of the GPs and find no correlation between GP emission phase and fractional polarisation. We use the GPs to time PSR B1937+21 and although the achievable time of arrival precision of the GPs is approximately a factor of two greater than that of the average pulse profile, there is a negligible difference in the precision of the overall timing solution when using the GPs., Comment: 20 pages, 21 figures, 3 tables, accepted for publication in MNRAS
Published: 2019
Full Text: View/download PDF

31. High-precision timing of 42 millisecond pulsars with the European Pulsar Timing Array

Author: P. Lazarus, R. van Haasteren, Christine Jordan, Pablo Rosado, Jason W. T. Hessels, S. Babak, Alberto Sesana, Joris P. W. Verbiest, Chiara M. F. Mingarelli, Benjamin Stappers, A. Jessner, D. J. Champion, J. W. McKee, J. R. Gair, Lucas Guillemot, Delphine Perrodin, Antoine Petiteau, P. Brem, Michael Kramer, Ramesh Karuppusamy, Andrew Lyne, Ismaël Cognard, Gregory Desvignes, Gilles Theureau, Kejia Lee, G. Shaifullah, E. Graikou, M. Burgay, Stefan Oslowski, M. B. Purver, Caterina Tiburzi, R. Smits, K. Lazaridis, Stephen Taylor, R. N. Caballero, Kang Liu, C. G. Bassa, A. Lassus, Gemma H. Janssen, Alberto Vecchio, S. Sanidas, L. Lentati, A. Possenti, Desvignes, G, Caballero, R, Lentati, L, Verbiest, J, Champion, D, Stappers, B, Janssen, G, Lazarus, P, Osłowski, S, Babak, S, Bassa, C, Brem, P, Burgay, M, Cognard, I, Gair, J, Graikou, E, Guillemot, L, Hessels, J, Jessner, A, Jordan, C, Karuppusamy, R, Kramer, M, Lassus, A, Lazaridis, K, Lee, K, Liu, K, Lyne, A, Mckee, J, Mingarelli, C, Perrodin, D, Petiteau, A, Possenti, A, Purver, M, Rosado, P, Sanidas, S, Sesana, A, Shaifullah, G, Smits, R, Taylor, S, Theureau, G, Tiburzi, C, van Haasteren, R, Vecchio, A, Max-Planck-Institut für Radioastronomie (MPIFR), Cavendish Laboratory, University of Cambridge [UK] (CAM), Universität Bielefeld, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Netherlands Institute for Radio Astronomy ( ASTRON ), Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft, INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), University of Amsterdam [Amsterdam] (UvA), Kavli Institute for Astronomy and Astrophysics [Beijing] (KIAA-PKU), Peking University [Beijing], APC - Gravitation (APC-Gravitation), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Centre for Astrophysics and Supercomputing [Swinburne] (CAS), Swinburne University of Technology [Melbourne], Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Theoretical Astrophysics [Pasadena] (TAPIR), California Institute of Technology (CALTECH), Birmingham City University (BCU), National Natural Science Foundation of China (Grant No.11373011)., European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Division of Physics, Mathematics and Astronomy [Pasadena], California Institute of Technology (CALTECH)-California Institute of Technology (CALTECH), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: astro-ph.SR, FOS: Physical sciences, Proper motion, Astrophysics, Magnetar, 01 natural sciences, Radio spectrum, Radio telescope, Pulsar timing array, proper motions, Pulsar, Millisecond pulsar, 0103 physical sciences, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Stars: Distance, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 010308 nuclear & particles physics, Pulsars: General, Astronomy, Astronomy and Astrophysics, pulsars:general, European Pulsar Timing Array, Neutron star, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, stars: distances, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, stars:distances, astro-ph.IM
Abstract: We report on the high-precision timing of 42 radio millisecond pulsars (MSPs) observed by the European Pulsar Timing Array (EPTA). This EPTA Data Release 1.0 extends up to mid-2014 and baselines range from 7-18 years. It forms the basis for the stochastic gravitational-wave background, anisotropic background, and continuous-wave limits recently presented by the EPTA elsewhere. The Bayesian timing analysis performed with TempoNest yields the detection of several new parameters: seven parallaxes, nine proper motions and, in the case of six binary pulsars, an apparent change of the semi-major axis. We find the NE2001 Galactic electron density model to be a better match to our parallax distances (after correction from the Lutz-Kelker bias) than the M2 and M3 models by Schnitzeler (2012). However, we measure an average uncertainty of 80\% (fractional) for NE2001, three times larger than what is typically assumed in the literature. We revisit the transverse velocity distribution for a set of 19 isolated and 57 binary MSPs and find no statistical difference between these two populations. We detect Shapiro delay in the timing residuals of PSRs J1600$-$3053 and J1918$-$0642, implying pulsar and companion masses $m_p=1.22_{-0.35}^{+0.5} \text{M}_{\odot}$, $m_c = 0.21_{-0.04}^{+0.06} \text{M}_{\odot }$ and $m_p=1.25_{-0.4}^{+0.6} \text{M}_{\odot}$, $m_c = 0.23_{-0.05}^{+0.07} \text{M}_{\odot }$, respectively. Finally, we use the measurement of the orbital period derivative to set a stringent constraint on the distance to PSRs J1012$+$5307 and J1909$-$3744, and set limits on the longitude of ascending node through the search of the annual-orbital parallax for PSRs J1600$-$3053 and J1909$-$3744., Comment: 42 pages, 11 figures. Accepted for publication in MNRAS
Published: 2016
Full Text: View/download PDF

32. From spin noise to systematics: stochastic processes in the first International Pulsar Timing Array data release

Author: R. van Haasteren, Scott M. Ransom, S. Babak, Antoine Petiteau, Paul Demorest, L. Toomey, Gemma H. Janssen, Alberto Sesana, Marjorie Gonzalez, Sourav Chatterjee, A. Lassus, Ryan Shannon, Justin A. Ellis, Glenn Jones, E. Graikou, J. W. McKee, Kang Liu, Kejia Lee, Matthew Kerr, Sarah Burke-Spolaor, William A. Coles, Maura McLaughlin, G. Shaifullah, Stephen Taylor, Weiwei Zhu, P. Lazarus, S. A. Sanidas, D. J. Champion, Delphine Perrodin, R. N. Caballero, Kevin Stovall, Joris P. W. Verbiest, Benetge Perera, Richard N. Manchester, C. G. Bassa, Emmanuel Fonseca, Jonathan R. Gair, George Hobbs, D. R. Madison, R. Smits, Alberto Vecchio, Daniel R. Stinebring, Michael T. Lam, Daniel J. Reardon, X. P. You, Zaven Arzoumanian, Paul D. Lasky, Yue-Fei Wang, Lucas Guillemot, R. S. Lynch, Pablo Rosado, Lina Levin, Xing-Jiang Zhu, Chiara M. F. Mingarelli, L. Lentati, Benjamin Stappers, A. Possenti, T. J. W. Lazio, Robert D. Ferdman, Stefan Oslowski, J. K. Swiggum, X. Siemens, Gregory Desvignes, Gilles Theureau, Ramesh Karuppusamy, Ismaël Cognard, M. Burgay, Timothy T. Pennucci, Michele Vallisneri, J. B. Wang, James M. Cordes, Sean T. McWilliams, David J. Nice, P. Brem, W. van Straten, Caterina Tiburzi, N. D. R. Bhat, Shi Dai, Jason W. T. Hessels, Ingrid H. Stairs, Timothy Dolch, Michael Kramer, Michael Keith, Lentati, L, Shannon, R, Coles, W, Verbiest, J, van Haasteren, R, Ellis, J, Caballero, R, Manchester, R, Arzoumanian, Z, Babak, S, Bassa, C, Bhat, N, Brem, P, Burgay, M, Burke-Spolaor, S, Champion, D, Chatterjee, S, Cognard, I, Cordes, J, Dai, S, Demorest, P, Desvignes, G, Dolch, T, Ferdman, R, Fonseca, E, Gair, J, Gonzalez, M, Graikou, E, Guillemot, L, Hessels, J, Hobbs, G, Janssen, G, Jones, G, Karuppusamy, R, Keith, M, Kerr, M, Kramer, M, Lam, M, Lasky, P, Lassus, A, Lazarus, P, Lazio, T, Lee, K, Levin, L, Liu, K, Lynch, R, Madison, D, Mckee, J, Mclaughlin, M, Mcwilliams, S, Mingarelli, C, Nice, D, Osłowski, S, Pennucci, T, Perera, B, Perrodin, D, Petiteau, A, Possenti, A, Ransom, S, Reardon, D, Rosado, P, Sanidas, S, Sesana, A, Shaifullah, G, Siemens, X, Smits, R, Stairs, I, Stappers, B, Stinebring, D, Stovall, K, Swiggum, J, Taylor, S, Theureau, G, Tiburzi, C, Toomey, L, Vallisneri, M, van Straten, W, Vecchio, A, Wang, J, Wang, Y, You, X, Zhu, W, Zhu, X, High Energy Astrophys. & Astropart. Phys (API, FNWI), Cavendish Laboratory, University of Cambridge [UK] (CAM), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), University of California, University of California (UC), Max-Planck-Institut für Radioastronomie (MPIFR), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), NASA Goddard Space Flight Center (GSFC), Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft, Netherlands Institute for Radio Astronomy (ASTRON), Curtin University [Perth], Planning and Transport Research Centre (PATREC), INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), National Radio Astronomy Observatory (NRAO), Center for Radiophysics and Space Research [Ithaca] (CRSR), Cornell University [New York], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Department of Astronomy [Ithaca], Department of Physics, Hillsdale College, Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), University of British Columbia (UBC), Vancouver Coastal Health, Department of Nuclear Medicine, Netherlands Institute for Radio Astronomy ( ASTRON ), ARC Centre of Excellence for Coral Reef Studies (CoralCoE), James Cook University (JCU), Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Vrije Universiteit Medical Centre (VUMC), Vrije Universiteit Amsterdam [Amsterdam] (VU), Kavli Institute for Astronomy and Astrophysics [Beijing] (KIAA-PKU), Peking University [Beijing], National Radio Astronomy Observatory [Green Bank] (NRAO), Jodrell Bank Centre for Astrophysics (JBCA), Department of Physics, West Virginia University, West Virginia University, Theoretical Astrophysics [Pasadena] (TAPIR), California Institute of Technology (CALTECH), Physics Department, Lafayette College, Lafayette College [Easton], Department of Astronomy [Charlottesville], University of Virginia, APC - Gravitation (APC-Gravitation), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre for Astrophysics and Supercomputing [Swinburne] (CAS), Swinburne University of Technology [Melbourne], Anton Pannekoek Institute for Astronomy, University of Amsterdam [Amsterdam] (UvA), University of Wisconsin - Milwaukee, Department of Physics and Astronomy, University of British Columbia, Department of Physics and Astronomy [Oberlin], Oberlin College, Institute of Meteoritics [Albuquerque] (IOM), The University of New Mexico [Albuquerque], Department of Physics and Astronomy, West Virginia University, West Virginia University [Morgantown], Birmingham City University (BCU), Xinjiang Astronomical Observatory, Chinese Academy of Sciences [Beijing] (CAS), Huazhong University of Science and Technology [Wuhan] (HUST), School of Physical Science and Technology, Southwest University [Chongqing], Australian Research Council Discovery Project DP140102578NASA through Einstein Fellowship grant PF3-140116West Light Foundation of CAS XBBS201322 and NSFC project no.11403086National Science Fundation of China (NSFC) award number 11503007NNSF of China (U1231120) and FRFCU (XDJK2015B012), European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), European Project: 227947,EC:FP7:ERC,ERC-2008-AdG,LEAP(2009), European Project: 610058,EC:FP7:ERC,ERC-2013-SyG,BLACKHOLECAM(2014), Cornell University, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Division of Physics, Mathematics and Astronomy [Pasadena], California Institute of Technology (CALTECH)-California Institute of Technology (CALTECH), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), California Institute of Technology (CALTECH)-NASA, Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), University of Virginia [Charlottesville], Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, data analysis, pulsars: general [methods], FOS: Physical sciences, General Relativity and Quantum Cosmology (gr-qc), Methods: Data analysi, Astrophysics, Astronomy & Astrophysics, general [pulsars], 01 natural sciences, General Relativity and Quantum Cosmology, pulsars:individual, Binary pulsar, Pulsar, 0103 physical sciences, data analysis [methods], Coherence (signal processing), Sensitivity (control systems), Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, Stochastic process, Noise (signal processing), Model selection, Pulsars: General, Astronomy and Astrophysics, methods: data analysis, LIGO, Computational physics, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astronomical and Space Sciences
Abstract: We analyse the stochastic properties of the 49 pulsars that comprise the first International Pulsar Timing Array (IPTA) data release. We use Bayesian methodology, performing model selection to determine the optimal description of the stochastic signals present in each pulsar. In addition to spin-noise and dispersion-measure (DM) variations, these models can include timing noise unique to a single observing system, or frequency band. We show the improved radio-frequency coverage and presence of overlapping data from different observing systems in the IPTA data set enables us to separate both system and band-dependent effects with much greater efficacy than in the individual PTA data sets. For example, we show that PSR J1643$-$1224 has, in addition to DM variations, significant band-dependent noise that is coherent between PTAs which we interpret as coming from time-variable scattering or refraction in the ionised interstellar medium. Failing to model these different contributions appropriately can dramatically alter the astrophysical interpretation of the stochastic signals observed in the residuals. In some cases, the spectral exponent of the spin noise signal can vary from 1.6 to 4 depending upon the model, which has direct implications for the long-term sensitivity of the pulsar to a stochastic gravitational-wave (GW) background. By using a more appropriate model, however, we can greatly improve a pulsar's sensitivity to GWs. For example, including system and band-dependent signals in the PSR J0437$-$4715 data set improves the upper limit on a fiducial GW background by $\sim 60\%$ compared to a model that includes DM variations and spin-noise only., Comment: 29 pages. 16 figures. Accepted for publication in MNRAS
Published: 2016
Full Text: View/download PDF

33. The International Pulsar Timing Array: First data release

Author: Lucas Guillemot, Sourav Chatterjee, N. Garver-Daniels, D. R. Madison, Scott M. Ransom, J. K. Swiggum, Daniel R. Stinebring, Delphine Perrodin, Ingrid H. Stairs, Alberto Vecchio, Timothy Dolch, X. Siemens, Gregory Desvignes, Antoine Petiteau, Gilles Theureau, W. van Straten, J. B. Wang, X. P. You, Jason W. T. Hessels, Renée Spiewak, R. N. Caballero, Alberto Sesana, Stefan Oslowski, R. S. Lynch, Xing-Jiang Zhu, C. G. Bassa, Emmanuel Fonseca, Daniel J. Reardon, Yue-Fei Wang, Chiara M. F. Mingarelli, Benjamin Stappers, Kejia Lee, Stanislav Babak, Benetge Perera, Pablo Rosado, Zaven Arzoumanian, Richard N. Manchester, Paul Demorest, A. Brazier, Jonathan R. Gair, R. van Haasteren, Nipuni Palliyaguru, Lina Levin, R. Smits, Joseph Simon, P. Brem, Michele Vallisneri, Michael Kramer, James M. Cordes, Andrew Lyne, L. Lentati, Weiwei Zhu, Matthew Kerr, Peter A. Gentile, Michael Keith, A. Possenti, D. J. Champion, Caterina Tiburzi, T. J. W. Lazio, N. D. R. Bhat, A. Lassus, Stephen Taylor, Linqing Wen, Ryan Shannon, Glenn Jones, Shi Dai, E. Graikou, Gemma H. Janssen, S. J. Chamberlin, Kevin Stovall, Kang Liu, P. Lazarus, Ramesh Karuppusamy, S. A. Sanidas, Ismaël Cognard, George Hobbs, Robert D. Ferdman, Timothy T. Pennucci, M. Burgay, Sean T. McWilliams, David J. Nice, B. Christy, G. Shaifullah, L. Toomey, Justin A. Ellis, J. W. McKee, Maura McLaughlin, Paul D. Lasky, Michael T. Lam, Sarah Burke-Spolaor, Joris P. W. Verbiest, Marjorie Gonzalez, High Energy Astrophys. & Astropart. Phys (API, FNWI), Verbiest, J, Lentati, L, Hobbs, G, van Haasteren, R, Demorest, P, Janssen, G, Wang, J, Desvignes, G, Caballero, R, Keith, M, Champion, D, Arzoumanian, Z, Babak, S, Bassa, C, Bhat, N, Brazier, A, Brem, P, Burgay, M, Burke-Spolaor, S, Chamberlin, S, Chatterjee, S, Christy, B, Cognard, I, Cordes, J, Dai, S, Dolch, T, Ellis, J, Ferdman, R, Fonseca, E, Gair, J, Garver-Daniels, N, Gentile, P, Gonzalez, M, Graikou, E, Guillemot, L, Hessels, J, Jones, G, Karuppusamy, R, Kerr, M, Kramer, M, Lam, M, Lasky, P, Lassus, A, Lazarus, P, Lazio, T, Lee, K, Levin, L, Liu, K, Lynch, R, Lyne, A, Mckee, J, Mclaughlin, M, Mcwilliams, S, Madison, D, Manchester, R, Mingarelli, C, Nice, D, Osłowski, S, Palliyaguru, N, Pennucci, T, Perera, B, Perrodin, D, Possenti, A, Petiteau, A, Ransom, S, Reardon, D, Rosado, P, Sanidas, S, Sesana, A, Shaifullah, G, Shannon, R, Siemens, X, Simon, J, Smits, R, Spiewak, R, Stairs, I, Stappers, B, Stinebring, D, Stovall, K, Swiggum, J, Taylor, S, Theureau, G, Tiburzi, C, Toomey, L, Vallisneri, M, van Straten, W, Vecchio, A, Wang, Y, Wen, L, You, X, Zhu, W, Zhu, X, Max-Planck-Institut für Radioastronomie (MPIFR), Cavendish Laboratory, University of Cambridge [UK] (CAM), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), National Radio Astronomy Observatory [Socorro] (NRAO), National Radio Astronomy Observatory (NRAO), Netherlands Institute for Radio Astronomy (ASTRON), Xinjiang Astronomical Observatory, Chinese Academy of Sciences [Beijing] (CAS), Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], NASA Goddard Space Flight Center (GSFC), Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft, Curtin University [Perth], Planning and Transport Research Centre (PATREC), Cornell Center for Astrophysics and Planetary Science (CCAPS), Cornell University [New York], INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Pennsylvania State University (Penn State), Penn State System, Center for Radiophysics and Space Research [Ithaca] (CRSR), University of Maryland [College Park], University of Maryland System, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Department of Astronomy [Ithaca], Department of Physics, Hillsdale College, University of British Columbia (UBC), University of Edinburgh, Department of Physics and Astronomy, West Virginia University, West Virginia University [Morgantown], Vancouver Coastal Health, Department of Nuclear Medicine, Department of Physics, Columbia University, Columbia University [New York], Monash Centre for Astrophysics (MoCA), Monash University [Clayton], Kavli Institute for Astronomy and Astrophysics [Beijing] (KIAA-PKU), Peking University [Beijing], National Radio Astronomy Observatory [Green Bank] (NRAO), Theoretical Astrophysics [Pasadena] (TAPIR), Division of Physics, Mathematics and Astronomy [Pasadena], California Institute of Technology (CALTECH)-California Institute of Technology (CALTECH), Physics Department, Lafayette College, Lafayette College [Easton], Physics Department, Texas Tech University, Texas Tech University [Lubbock] (TTU), Department of Astronomy [Charlottesville], University of Virginia [Charlottesville], APC - Gravitation (APC-Gravitation), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Centre for Astrophysics and Supercomputing [Swinburne] (CAS), Swinburne University of Technology [Melbourne], Anton Pannekoek Institute for Astronomy, University of Amsterdam [Amsterdam] (UvA), University of Wisconsin - Milwaukee, Center for Gravitation, Cosmology and Astrophysics, Netherlands Institute for Radio Astronomy ( ASTRON ), Department of Physics and Astronomy, University of British Columbia, Department of Physics and Astronomy [Oberlin], Oberlin College, Department of Physics and Astronomy [Albuquerque], The University of New Mexico [Albuquerque], Birmingham City University (BCU), School of Physics [HUST], Huazhong University of Science and Technology [Wuhan] (HUST), School of Physics (University of Western Australia), Université, School of Physical Science and Technology, Southwest University [Chongqing], European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), Max-Planck-Institut für Radioastronomie, Cavendish Laboratory - University of Cambridge, University of Cambridge [UK] ( CAM ), CSIRO Astronomy and Space Science, PO BOX 76, NSW 1710, Australia, Jet Propulsion Laboratory ( JPL ), NASA-California Institute of Technology ( CALTECH ), National Radio Astronomy Observatory [Socorro] ( NRAO ), National Radio Astronomy Observatory ( NRAO ), Netherlands Institute for Radio Astronomy, Chinese Academy of Sciences [Beijing] ( CAS ), NASA Goddard Space Flight Center ( GSFC ), Albert Einstein Institute, Max-Planck-Institut für Gravitationsphysik, Curtin University, Perth, Australia, Cornell Center for Astrophysics and Planetary Science ( CCAPS ), Cornell University, MPI for Gravitational Physics (Albert Einstein Institute), INAF-Osservatorio di Cagliari, PennState University [Pennsylvania] ( PSU ), Center for Radiophysics and Space Research [Ithaca] ( CRSR ), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS ), Unité Scientifique de la Station de Nançay ( USN ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire de Paris-Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS ), University of British Columbia ( UBC ), University of Edimburgh, Kavli Institute for Astronomy and Astrophysics, National Radio Astronomy Observatory [Green Bank] ( NRAO ), Commonwealth Scientific and Industrial Research Organisation [Canberra] ( CSIRO ), TAPIR (Theoretical Astrophysics), California Institute of Technology, Texas Tech University [Lubbock] ( TTU ), Osservatorio Astronomico di Cagliari, Ist Nazl Astrofis, Osservatorio Astronomico di Cagliari, APC - Gravitation ( APC-Gravitation ), AstroParticule et Cosmologie ( APC - UMR 7164 ), Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Observatoire de Paris-Université Paris Diderot - Paris 7 ( UPD7 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut), Max-Planck-Institut-Max-Planck-Institut, Centre for Astrophysics and Supercomputing [Swinburne] ( CAS ), Anton Pannekoek Institute for Astronomy, University of Amsterdam, Max Planck Institut für Gravitationsphysik, Albert Einstein Institut, Physics and Astronomy Department [Oberlin], Center for Gravitational Wave Astronomy, The University of Texas at Brownsville and Texas Southmost College, Birmingham City University ( BCU ), School of Physics, Huazhong University of Science and Technology, Huazhong University of Science and Technology, School of Physics ( University of Western Australia ), European Project : 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET ( 2014 ), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), California Institute of Technology (CALTECH), University of Virginia, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI)
Subjects: data analysis, data analysis, pulsars: general [methods], FOS: Physical sciences, Methods: Data analysi, general [pulsars], 01 natural sciences, 7. Clean energy, Set (abstract data type), Pulsar timing array, Pulsar, 0103 physical sciences, data analysis [methods], Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, instrumentation, Physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 010308 nuclear & particles physics, Gravitational wave, Astrophysics::Instrumentation and Methods for Astrophysics, Pulsars: General, Astronomy, Astronomy and Astrophysics, methods: data analysis, Data set, European Pulsar Timing Array, Neutron star, gravitational waves, Space and Planetary Science, pulsars, Measurement uncertainty, Astrophysics - Instrumentation and Methods for Astrophysics, [ SDU.ASTR.SR ] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Algorithm, astro-ph.IM
Abstract: The highly stable spin of neutron stars can be exploited for a variety of (astro-)physical investigations. In particular arrays of pulsars with rotational periods of the order of milliseconds can be used to detect correlated signals such as those caused by gravitational waves. Three such "Pulsar Timing Arrays" (PTAs) have been set up around the world over the past decades and collectively form the "International" PTA (IPTA). In this paper, we describe the first joint analysis of the data from the three regional PTAs, i.e. of the first IPTA data set. We describe the available PTA data, the approach presently followed for its combination and suggest improvements for future PTA research. Particular attention is paid to subtle details (such as underestimation of measurement uncertainty and long-period noise) that have often been ignored but which become important in this unprecedentedly large and inhomogeneous data set. We identify and describe in detail several factors that complicate IPTA research and provide recommendations for future pulsar timing efforts. The first IPTA data release presented here (and available online) is used to demonstrate the IPTA's potential of improving upon gravitational-wave limits placed by individual PTAs by a factor of ~2 and provides a 2-sigma limit on the dimensionless amplitude of a stochastic GWB of 1.7x10^{-15} at a frequency of 1 yr^{-1}. This is 1.7 times less constraining than the limit placed by (Shannon et al. 2015), due mostly to the more recent, high-quality data they used., 25 pages, 6 tables, 5 figures. Accepted for publication in MNRAS
Published: 2016
Full Text: View/download PDF

34. Timing of 29 Pulsars Discovered in the PALFA Survey

Author: Fredrick A. Jenet, P. Lazarus, J. M. Cordes, Julia Deneva, Wei Zhu, Heinz-Bernd Eggenstein, J. van Leeuwen, C. Aulbert, Xavier Siemens, H. Fehrmann, B. Machenschalk, Ryan Lynch, A. Seymour, Benjamin William Allen, Scott M. Ransom, Fronefield Crawford, Joseph K. Swiggum, O. Bock, E. Madsen, Ben Stappers, Paul Scholz, Victoria M. Kaspi, J. W. McKee, Robert Wharton, Maura McLaughlin, Shami Chatterjee, Fernando Camilo, C. Patel, Kevin Stovall, E. Parent, D. R. Lorimer, Andrew Lyne, Adam Brazier, Benjamin Knispel, Robert D. Ferdman, Ingrid H. Stairs, Paulo C. C. Freire, Slavko Bogdanov, Jason W. T. Hessels, Laura Spitler, F. Cardoso, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Rotation period, general, pulsars: individual: PSR J0611+1436, PSR J1907+0631, PSR J1925+1720, PSR J1932+1500 [pulsars], education.field_of_study, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Population, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, Jodrell Bank Observatory, Astrophysics, 01 natural sciences, Neutron star, Supernova, Pulsar, 13. Climate action, Space and Planetary Science, 0103 physical sciences, education, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Fermi Gamma-ray Space Telescope, Radio astronomy
Abstract: We report on the discovery and timing observations of 29 distant long-period pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Following discovery with the Arecibo Telescope, confirmation and timing observations of these pulsars over several years at Jodrell Bank Observatory have yielded high-precision positions and measurements of rotation and radiation properties. We have used multi-frequency data to measure the interstellar scattering properties of some of these pulsars. Most of the pulsars have properties that mirror those of the previously known pulsar population, although four show some notable characteristics. PSRs J1907+0631 and J1925+1720 are young and are associated with supernova remnants or plerionic nebulae: J1907+0631 lies close to the center of SNR G40.5-0.5, while J1925+1720 is coincident with a high-energy Fermi gamma-ray source. One pulsar, J1932+1500, is in a surprisingly eccentric, 199-day binary orbit with a companion having a minimum mass of 0.33 solar masses. Several of the sources exhibit timing noise, and two, PSRs J0611+1436 and J1907+0631, have both suffered large glitches, but with very different post-glitch rotation properties. In particular, the rotational period of PSR J0611+1436 will not recover to its pre-glitch value for about 12 years, a far greater recovery timescale than seen following any other large glitches., 30 pages, 8 Figures, accepted by ApJ, accepted version
Published: 2016
Full Text: View/download PDF

35. The noise properties of 42 millisecond pulsars from the European Pulsar Timing Array and their impact on gravitational-wave searches

Author: Chiara M. F. Mingarelli, Benjamin Stappers, Alberto Vecchio, S. Babak, Caterina Tiburzi, R. N. Caballero, Kang Liu, A. Lassus, Stefan Oslowski, C. G. Bassa, Delphine Perrodin, Lucas Guillemot, R. van Haasteren, Kejia Lee, P. Brem, E. Graikou, Jason W. T. Hessels, Joris P. W. Verbiest, Pablo Rosado, M. B. Purver, D. J. Champion, Gemma H. Janssen, Ramesh Karuppusamy, Ismaël Cognard, Jonathan R. Gair, G. Shaifullah, J. W. McKee, Stephen Taylor, Michael Kramer, Antoine Petiteau, R. Smits, Alberto Sesana, P. Lazarus, S. Sanidas, L. Lentati, M. Burgay, A. Possenti, Gregory Desvignes, Gilles Theureau, High Energy Astrophys. & Astropart. Phys (API, FNWI), Caballero, R, Lee, K, Lentati, L, Desvignes, G, Champion, D, Verbiest, J, Janssen, G, Stappers, B, Kramer, M, Lazarus, P, Possenti, A, Tiburzi, C, Perrodin, D, Osłowski, S, Babak, S, Bassa, C, Brem, P, Burgay, M, Cognard, I, Gair, J, Graikou, E, Guillemot, L, Hessels, J, Karuppusamy, R, Lassus, A, Liu, K, Mckee, J, Mingarelli, C, Petiteau, A, Purver, M, Rosado, P, Sanidas, S, Sesana, A, Shaifullah, G, Smits, R, Taylor, S, Theureau, G, van Haasteren, R, Vecchio, A, Max-Planck-Institut für Radioastronomie (MPIFR), Kavli Institute for Astronomy and Astrophysics [Beijing] (KIAA-PKU), Peking University [Beijing], Cavendish Laboratory, University of Cambridge [UK] (CAM), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Columbia Astrophysics Laboratory (CAL), Columbia University [New York], Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Universität Bielefeld, Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft, Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), School of Mathematics - University of Edinburgh, University of Edinburgh, Netherlands Institute for Radio Astronomy (ASTRON), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), APC - Gravitation (APC-Gravitation), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Netherlands Institute for Radio Astronomy ( ASTRON ), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), School of Physics and Astronomy [Birmingham], University of Birmingham [Birmingham], Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), California Institute of Technology (CALTECH)-NASA, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI)
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, 01 natural sciences, Binary pulsar, Pulsar, Millisecond pulsar, pulsars: general, 0103 physical sciences, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, gravitational waves – methods: data analysis – pulsars: general, Physics, Supermassive black hole, 010308 nuclear & particles physics, Gravitational wave, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, methods: data analysis, European Pulsar Timing Array, Amplitude, gravitational waves, 13. Climate action, Space and Planetary Science, Astrophysics - Instrumentation and Methods for Astrophysics, Noise (radio), Astrophysics - Cosmology and Nongalactic Astrophysics, Methods: data analysi
Abstract: The sensitivity of Pulsar Timing Arrays to gravitational waves depends on the noise present in the individual pulsar timing data. Noise may be either intrinsic or extrinsic to the pulsar. Intrinsic sources of noise will include rotational instabilities, for example. Extrinsic sources of noise include contributions from physical processes which are not sufficiently well modelled, for example, dispersion and scattering effects, analysis errors and instrumental instabilities. We present the results from a noise analysis for 42 millisecond pulsars (MSPs) observed with the European Pulsar Timing Array. For characterising the low-frequency, stochastic and achromatic noise component, or "timing noise", we employ two methods, based on Bayesian and frequentist statistics. For 25 MSPs, we achieve statistically significant measurements of their timing noise parameters and find that the two methods give consistent results. For the remaining 17 MSPs, we place upper limits on the timing noise amplitude at the 95% confidence level. We additionally place an upper limit on the contribution to the pulsar noise budget from errors in the reference terrestrial time standards (below 1%), and we find evidence for a noise component which is present only in the data of one of the four used telescopes. Finally, we estimate that the timing noise of individual pulsars reduces the sensitivity of this data set to an isotropic, stochastic GW background by a factor of >9.1 and by a factor of >2.3 for continuous GWs from resolvable, inspiralling supermassive black-hole binaries with circular orbits., Accepted for publication by the Monthly Notices of the Royal Astronomical Society
Published: 2016
Full Text: View/download PDF

36. A millisecond pulsar in an extremely wide binary system

Author: Benjamin Stappers, R. Smits, Kejia Lee, Lucas Guillemot, E. Graikou, R. N. Caballero, C. G. Bassa, Gemma H. Janssen, P. Lazarus, Joris P. W. Verbiest, Weiwei Zhu, Thomas Wevers, Peter G. Jonker, Ramesh Karuppusamy, S. Sanidas, G. Shaifullah, Ismaël Cognard, Andrew Lyne, A. Jessner, J. W. McKee, Michael Kramer, Caterina Tiburzi, K. Lazaridis, Stefan Oslowski, Paulo C. C. Freire, D. J. Champion, Thomas M. Tauris, Kang Liu, Christine Jordan, Delphine Perrodin, L. Lentati, Gregory Desvignes, Gilles Theureau, Netherlands Institute for Radio Astronomy (ASTRON), Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Max-Planck-Institut für Radioastronomie (MPIFR), Department of Astrophysics [Nijmegen], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen]-Radboud university [Nijmegen], SRON Netherlands Institute for Space Research (SRON), Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), Fakultät für Physik, Universität Bielefeld, Universität Bielefeld, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Kavli Institute for Astronomy and Astrophysics [Beijing] (KIAA-PKU), Peking University [Beijing], INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Anton Pannekoek Institute for Astronomy, University of Amsterdam [Amsterdam] (UvA), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Programme National de Cosmologie and Galaxies' (PNCG) of CNRS/INSU, France., European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), European Project: 610058,EC:FP7:ERC,ERC-2013-SyG,BLACKHOLECAM(2014), ITA, GBR, FRA, DEU, TWN, NLD, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Bassa, C, Janssen, G, Stappers, B, Tauris, T, Wevers, T, Jonker, P, Lentati, L, Verbiest, J, Desvignes, G, Graikou, E, Guillemot, L, Freire, P, Lazarus, P, Caballero, R, Champion, D, Cognard, I, Jessner, A, Jordan, C, Karuppusamy, R, Kramer, M, Lazaridis, K, Lee, K, Liu, K, Lyne, A, Mckee, J, Osłowski, S, Perrodin, D, Sanidas, S, Shaifullah, G, Smits, R, Theureau, G, Tiburzi, C, Zhu, W, Radboud University [Nijmegen]-Radboud University [Nijmegen], Universität Bielefeld = Bielefeld University, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: stars: individual: PSR J1024-0719, Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Pulsar planet, Supernovae: general, FOS: Physical sciences, Astrophysics, 01 natural sciences, Binary pulsar, stars: neutron, Pulsar, Millisecond pulsar, 0103 physical sciences, 010306 general physics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], supernovae: general, Astronomy and Astrophysics, European Pulsar Timing Array, Neutron star, binaries: general, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Sub-Earth, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, X-ray pulsar
Abstract: We report on 22 yrs of radio timing observations of the millisecond pulsar J1024$-$0719 by the telescopes participating in the European Pulsar Timing Array (EPTA). These observations reveal a significant second derivative of the pulsar spin frequency and confirm the discrepancy between the parallax and Shklovskii distances that has been reported earlier. We also present optical astrometry, photometry and spectroscopy of 2MASS J10243869$-$0719190. We find that it is a low-metallicity main-sequence star (K7V spectral type, $\mathrm{[M/H]}=-1.0$, $T_\mathrm{eff}=4050\pm50$ K) and that its position, proper motion and distance are consistent with those of PSR J1024$-$0719. We conclude that PSR J1024$-$0719 and 2MASS J10243869$-$0719190 form a common proper motion pair and are gravitationally bound. The gravitational interaction between the main-sequence star and the pulsar accounts for the spin frequency derivatives, which in turn resolves the distance discrepancy. Our observations suggest that the pulsar and main-sequence star are in an extremely wide ($P_\mathrm{b}>200$ yr) orbit. Combining the radial velocity of the companion and proper motion of the pulsar, we find that the binary system has a high spatial velocity of $384\pm45$ km s$^{-1}$ with respect to the local standard of rest and has a Galactic orbit consistent with halo objects. Since the observed main-sequence companion star cannot have recycled the pulsar to millisecond spin periods, an exotic formation scenario is required. We demonstrate that this extremely wide-orbit binary could have evolved from a triple system that underwent an asymmetric supernova explosion, though find that significant fine-tuning during the explosion is required. Finally, we discuss the implications of the long period orbit on the timing stability of PSR J1024$-$0719 in light of its inclusion in pulsar timing arrays., 16 pages, 12 figures, 2 tables, submitted for publication in MNRAS
Published: 2016
Full Text: View/download PDF

37. LEAP : The Large European Array for Pulsars

Author: R. Smits, Kejia Lee, Kang Liu, S. Sanidas, M. B. Purver, Ramesh Karuppusamy, Michael Kramer, Gemma H. Janssen, Delphine Perrodin, Benjamin Stappers, J. W. McKee, C. G. Bassa, ITA, GBR, FRA, DEU, TWN, NLD, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Netherlands Institute for Radio Astronomy ( ASTRON ), Max-Planck-Institut für Radioastronomie (MPIFR), Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Jodrell Bank Centre for Astrophysics (JBCA), INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), National Basic Research Program of China, 973 Program, 2015CB857101 and NSFC 11373011, European Project: 227947,EC:FP7:ERC,ERC-2008-AdG,LEAP(2009), High Energy Astrophys. & Astropart. Phys (API, FNWI), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, law.invention, Radio telescope, Telescope, Pulsar, law, 0103 physical sciences, ComputingMethodologies_SYMBOLICANDALGEBRAICMANIPULATION, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, 010308 nuclear & particles physics, Gravitational wave, Antenna aperture, Bandwidth (signal processing), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], European Pulsar Timing Array, Space and Planetary Science, Astrophysics - Instrumentation and Methods for Astrophysics, data analysis, techniques: interferometric, pulsars: general [gravitational waves, methods], Radio wave
Abstract: The Large European Array for Pulsars (LEAP) is an experiment that harvests the collective power of Europe's largest radio telescopes in order to increase the sensitivity of high-precision pulsar timing. As part of the ongoing effort of the European Pulsar Timing Array (EPTA), LEAP aims to go beyond the sensitivity threshold needed to deliver the first direct detection of gravitational waves. The five telescopes presently included in LEAP are: the Effelsberg telescope, the Lovell telescope at Jodrell Bank, the Nan\c cay radio telescope, the Sardinia Radio Telescope and the Westerbork Synthesis Radio Telescope. Dual polarization, Nyquist-sampled time-series of the incoming radio waves are recorded and processed offline to form the coherent sum, resulting in a tied-array telescope with an effective aperture equivalent to a 195-m diameter circular dish. All observations are performed using a bandwidth of 128 MHz centered at a frequency of 1396 MHz. In this paper, we present the design of the LEAP experiment, the instrumentation, the storage and transfer of data, and the processing hardware and software. In particular, we present the software pipeline that was designed to process the Nyquist-sampled time-series, measure the phase and time delays between each individual telescope and a reference telescope and apply these delays to form the tied-array coherent addition. The pipeline includes polarization calibration and interference mitigation. We also present the first results from LEAP and demonstrate the resulting increase in sensitivity, which leads to an improvement in the pulse arrival times., 15 pages, 12 figures, accepted for publication in MNRAS
Published: 2016
Full Text: View/download PDF

38. 21 year timing of the black-widow pulsar J2051-0827

Author: Caterina Tiburzi, E. Graikou, Gemma H. Janssen, Norbert Wex, A. Possenti, Christine Jordan, Ben Stappers, Andrew Lyne, R. N. Caballero, Stefan Oslowski, Lucas Guillemot, Michael Kramer, Gregory Desvignes, K. Lazaridis, C. G. Bassa, Axel Jessner, G. Shaifullah, D. J. Champion, P. Lazarus, J. W. McKee, Ramesh Karuppusamy, Ismaël Cognard, Joris P. W. Verbiest, Delphine Perrodin, Thomas M. Tauris, Paulo C. C. Freire, Shaifullah, G, Verbiest, J, Freire, P, Tauris, T, Wex, N, Osłowski, S, Stappers, B, Bassa, C, Caballero, R, Champion, D, Cognard, I, Desvignes, G, Graikou, E, Guillemot, L, Janssen, G, Jessner, A, Jordan, C, Karuppusamy, R, Kramer, M, Lazaridis, K, Lazarus, P, Lyne, A, Mckee, J, Perrodin, D, Possenti, A, Tiburzi, C, Max-Planck-Institut für Radioastronomie (MPIFR), Universität Bielefeld, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Columbia Astrophysics Laboratory (CAL), Columbia University [New York], Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft, INAF - Osservatorio Astronomico di Cagliari (OAC), Istituto Nazionale di Astrofisica (INAF), European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), and Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Proper motion, general pulsars individual, individual: PSR J2051-0827, Pulsar planet, Binaries: eclipsing, FOS: Physical sciences, fundamental properties pulsars, Astrophysics, 01 natural sciences, Binary pulsar, Radio telescope, Pulsars: individual: PSR J2051-0827, Pulsar, Millisecond pulsar, Binaries: close, 0103 physical sciences, pulsars, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, binaries:close stars, PSR J2051−0827, European Pulsar Timing Array, Pulsars: general, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), binaries:eclipsing, Astrophysics - High Energy Astrophysical Phenomena, X-ray pulsar
Abstract: Timing results for the black-widow pulsar J2051-0827 are presented, using a 21-year dataset from four European Pulsar Timing Array telescopes and the Parkes radio telescope. This dataset, which is the longest published to date for a black-widow system, allows for an improved analysis that addresses previously unknown biases. While secular variations, as identified in previous analyses, are recovered, short-term variations are detected for the first time. Concurrently, a significant decrease of approx. 2.5x10-3 cm-3 pc in the dispersion measure associated with PSR J2051-0827 is measured for the first time and improvements are also made to estimates of the proper motion. Finally, PSR J2051-0827 is shown to have entered a relatively stable state suggesting the possibility of its eventual inclusion in pulsar timing arrays., Accepted for publication by MNRAS, 10 pages, 6 figures
Published: 2016
Full Text: View/download PDF

39. A double-blind, placebo-controlled interaction study between oxcarbazepine and carbamazepine, sodium valproate and phenytoin in epileptic patients

Author: R. A. Gillham, M. J. Brodie, G. Forrest, D. Connelly, S. M. Walker, P. J. W. Mckee, and Jackie Blacklaw
Subjects: Adult, Male, Phenytoin, medicine.medical_treatment, Oxcarbazepine, Placebo, Double-Blind Method, Pharmacokinetics, medicine, Humans, Drug Interactions, Pharmacology (medical), Active metabolite, Pharmacology, Epilepsy, business.industry, Valproic Acid, Carbamazepine, Middle Aged, Drug interaction, Anticonvulsant, Anesthesia, Anticonvulsants, Female, business, Research Article, Half-Life, medicine.drug
Abstract: 1. The effect of carbamazepine (CBZ), sodium valproate (VPA) and phenytoin (PHT) on the pharmacokinetics of oxcarbazepine (OXC) was explored in three groups of 12 epileptic patients taking one of these drug as monotherapy. 2. Each patient took a single 600 mg dose of OXC followed 7 days later by 3 weeks' treatment with OXC 300 mg thrice daily and matched placebo in random order. 3. Seven untreated patients, acting as controls, were prescribed the single OXC dose and 3 weeks' active treatment only. 4. In those patients completing the study, the area under the concentration-time curve (AUC) at steady-state for hydroxycarbazepine (OHCZ), the active metabolite of OXC, was significantly lower in the CBZ-treated group than in controls (P < 0.05). 5. No other differences in AUCs or elimination half-lives for OHCZ were found between treated and untreated patients following single or multiple OXC dosing. 6. Median AUCs of CBZ, VPA and PHT during a dosage interval did not differ significantly after treatment with OXC and placebo. 7. Ten patients completing the study complained of side-effects during treatment with OXC compared with one taking placebo (P < 0.01). 8. There were no important changes in cognitive function testing during administration of OXC compared with placebo. 9. Standard doses of OXC can be given as add-on therapy in epileptic patients receiving CBZ, VPA or PHT without producing a clinically relevant pharmacokinetic interaction.
Published: 1994
Full Text: View/download PDF

40. Effect of vigabatrin on sedation and cognitive function in patients with refractory epilepsy

Author: J. Blacklaw, P. J. W. Mckee, MartinJ. Brodie, and R A Gillham
Subjects: Adult, Male, Time Factors, Adolescent, genetic structures, Sedation, medicine.medical_treatment, Neuropsychological Tests, Placebo, Vigabatrin, Epilepsy, Cognition, Double-Blind Method, Memory, medicine, Humans, Aminocaproates, Psychomotor learning, Analysis of Variance, Neuropsychology, Middle Aged, medicine.disease, Crossover study, Psychiatry and Mental health, Anticonvulsant, Anesthesia, Anticonvulsants, Female, Surgery, Neurology (clinical), medicine.symptom, Sleep, Psychology, Follow-Up Studies, Research Article, medicine.drug
Abstract: Twenty-four patients with refractory epilepsy on one or more antiepileptic drugs were given additional vigabatrin (1 g twice daily for six weeks, followed by 1.5 g twice daily for a further six weeks) and matched placebo in a double blind, randomised, crossover study. A battery of neuropsychological tests was administered at baseline and at weeks two, six and 12 of both treatment periods. No significant differences were found between vigabatrin and placebo at any time point for any of the objective tests of cognitive function. Patients, however, reported a greater degree of sedation after two and six weeks on vigabatrin than during the equivalent placebo phase (p < 0.01), although no such difference was apparent at 12 weeks. Follow up over a mean of 14.75 months in 12 responders, who continued on vigabatrin, revealed a significant improvement (all p < 0.01) on each of three composite scales (three psychomotor tests, four memory tests, three self rating scales) compared with their scores during the double blind trial. Vigabatrin did not cause cognitive impairment either acutely or in the long term. Phased introduction, however, seems a prudent policy to allow tolerance to early subjective sedation.
Published: 1993
Full Text: View/download PDF

41. Double dummy comparison between once and twice daily dosing with modified-release carbamazepine in epileptic patients

Author: P. J. W. Mckee, R. A. Gillham, J. Blacklaw, M. J. Brodie, and A. Carswell
Subjects: Adult, Male, Cmax, Placebo, Drug Administration Schedule, Cmin, Double-Blind Method, medicine, Humans, Pharmacology (medical), Dosing, Morning, Pharmacology, Cross-Over Studies, Epilepsy, business.industry, Carbamazepine, Middle Aged, Crossover study, Anesthesia, Anticonvulsants, Female, business, Research Article, medicine.drug, Blood sampling
Abstract: 1. Fourteen patients with refractory epilepsy on a twice daily regimen of modified-release carbamazepine (CBZ-MR. Tegretol Retard. Ciba Pharmaceuticals) completed a balanced, double-blind, double dummy, random order, crossover comparison of 8 weeks treatment with once (o.d.) and twice daily (b.d.) dosing. In order to obtain a profile of serum CBZ concentrations over 24 h on once daily dosing, patients were randomised to taking it in the morning (o.d. a.m.) or evening (o.d. p.m.) for 4 weeks. Each treatment was taken with a placebo of the other and total tablet numbers were matched. Blood sampling was undertaken 0, 2, 4, 6, 8, 10, 12 and 24 h after the morning tablets at the end of each 4 week treatment period. 2. Overall, trough serum drug concentrations (Cmin) were lower with once daily dosing (Cmin: b.d. 7.5 mg l-1, o.d. 6.5 mg l-1, P < 0.05, 95% CI of the difference -1.3 to -0.1), but no significant differences were found in average (Cav) or peak (Cmax) concentrations, AUC values or fluctuations in CBZ concentrations. 3. Pharmacokinetic parameters for CBZ 10.11 epoxide, the active metabolite of CBZ did not differ significantly between the dosage schedules. 4. Seizure control was similar during once and twice daily dosing with CBZ-MR (median seizures/month (range): b.d. 1 (0-14.5), o.d. 0.5 (0-11), NS, 95% CI of the difference -1.8 to + 0.25). 5. There were no differences in psychomotor performance between the treatment periods. 6. More patients (n = 11) preferred treatment (P < 0.05) with once daily than twice daily dosing (n = 3) with CBZ-MR. 7. Once daily dosing with CBZ-MR should be possible in the majority of patients receiving the drug as monotherapy.
Published: 1993
Full Text: View/download PDF

42. Variability and clinical relevance of the interaction between sodium valproate and carbamazepine in epileptic patients

Author: Elaine Butler, J. Blacklaw, MartinJ. Brodie, P. J. W. Mckee, and R. A. Gillham
Subjects: Adult, Male, Adolescent, medicine.medical_treatment, Sodium, chemistry.chemical_element, Pharmacology, Epilepsy, Cognition, Pharmacokinetics, medicine, Humans, Drug Interactions, Active metabolite, Chemotherapy, business.industry, Valproic Acid, Carbamazepine, Middle Aged, Drug interaction, medicine.disease, Anticonvulsant, Neurology, chemistry, Female, lipids (amino acids, peptides, and proteins), Neurology (clinical), business, medicine.drug
Abstract: Twenty-four epileptic patients (16 females, 8 males; aged 13-62 years) were studied before and after the addition of sodium valproate (VPA) 500 mg twice daily for 5 days. All had been established previously on carbamazepine (CBZ) as monotherapy (300-1600 mg daily in divided doses). Sixteen of these patients undertook a battery of cognitive function tests before and after VPA introduction. VPA had no effect on total or free CBZ concentrations. However, median concentrations of the active metabolite, CBZ 10,11 epoxide (CBZ-E), were significantly increased (CBZ-E before VPA 1.3 mg/l, after VPA 2.1 mg/l, P less than 0.01). The median rise was 25%, although the extent of the interaction ranged from a 25% decrease to an increase of 123% in CBZ-E concentrations. This was related to the marked inter-individual variation in circulating VPA (mean 25-69 mg/l), as CBZ-E concentrations correlated significantly with total (r = 0.5, P less than 0.05, 95% CI 0 to +0.08) and free (r = 0.7, P less than 0.001, 95% CI +0.09 to +0.25) VPA levels in individual patients. Although uncontrolled, no deterioration in performance of any of the cognitive function tests was observed following the addition of VPA. This study does not support immediate clinical relevance for this drug interaction between VPA and CBZ.
Published: 1992
Full Text: View/download PDF

43. Rapid tolerance to acute psychomotor impairment with carbamazepine in epileptic patients

Author: M. J. Brodie, P. J. W. Mckee, and J. G. Larkin
Subjects: Adult, Male, medicine.medical_specialty, Adolescent, medicine.medical_treatment, Gastroenterology, Epilepsy, Oral administration, Internal medicine, Humans, Medicine, Pharmacology (medical), Active metabolite, Pharmacology, Psychomotor learning, Psychomotor function, business.industry, Drug Tolerance, Carbamazepine, Middle Aged, medicine.disease, Anticonvulsant, Anesthesia, Finger tapping, Female, business, Psychomotor Performance, Research Article, medicine.drug
Abstract: Thirteen patients with newly diagnosed epilepsy performed a battery of psychomotor function tests before and during the first 12 weeks of carbamazepine (CBZ) therapy. Movement time (P less than 0.025), total choice reaction time (P less than 0.025), finger tapping rate (P less than 0.005) and number cancellation (P less than 0.05) were all significantly impaired after 1 week's treatment, but had returned to baseline by 4 weeks. Mean (+/- s.d.) serum CBZ concentrations and those of its active metabolite CBZ 10,11 epoxide (CBZ-E) were comparable at 1 (CBZ: 8.5 +/- 2.1 mg l-1, CBZ-E: 1.1 +/- 0.68 mg l-1) and 4 weeks (CBZ: 8.1 +/- 4.4 mg l-1, CBZ-E: 0.93 +/- 0.27 mg l-1). These results suggest the rapid development of tolerance to the acute deleterious psychomotor effects of CBZ.
Published: 1992
Full Text: View/download PDF

44. Nimodipine in refractory epilepsy: A placebo-controlled, add-on study

Author: J. G. Larkin, P. J. W. Mckee, MartinJ. Brodie, G. G. Thompson, J. Blacklaw, and I.C Morgan
Subjects: Adult, Male, Adolescent, medicine.medical_treatment, Blood Pressure, Placebo, Epilepsy, Double-Blind Method, medicine, Humans, Pulse, Nimodipine, Polypharmacy, business.industry, Middle Aged, medicine.disease, Crossover study, Clinical trial, Anticonvulsant, Blood pressure, Neurology, Anesthesia, Female, Epilepsies, Partial, Neurology (clinical), business, medicine.drug
Abstract: Twenty-two patients (8 male, 14 female) with refractory epilepsy entered a balanced, double-blind, placebo-controlled crossover trial of nimodipine as adjunctive therapy. Treatment periods of 12 weeks (nimodipine 30 mg tds, 60 mg tds, 90 mg tds each for 4 weeks and matched placebo) were followed by wash-out intervals of 4 weeks. Five patients withdrew (2 side-effects, 1 intercurrent illness, 2 non-compliance). Median values (placebo vs. nimodipine) did not vary for total (17 vs. 18), partial (14 vs. 18) and generalised tonic-clonic seizures (2 vs. 5) or seizure days (13 vs. 13). Monthly analysis also failed to uncover any benefit for nimodipine. Side-effects were reported no more frequently with nimodipine than with placebo and pulse and blood pressure did not alter significantly. Antiepileptic drug levels were not affected by nimodipine treatment but circulating nimodipine concentrations were low. In this trial, nimodipine did not fulfil the promise of its success in animal models of epilepsy. Enzyme induction by concurrent antiepileptic therapy may provide an explanation.
Published: 1991
Full Text: View/download PDF

45. Physical and comparative mapping of distal mouse chromosome 16. 5 p5

Author: D E, Cabin, J W, McKee-Johnson, L E, Matesic, T, Wiltshire, E E, Rue, A E, Mjaatvedt, Y K, Huo, J R, Korenberg, and R H, Reeves
Subjects: Expressed Sequence Tags, Genetic Markers, Letter, Chromosomes, Human, Pair 21, Molecular Sequence Data, Trisomy, Blotting, Northern, Physical Chromosome Mapping, Chromosomes, Contig Mapping, Disease Models, Animal, Mice, Animals, Humans, RNA, Down Syndrome, Sequence Tagged Sites
Abstract: Distal mouse Chromosome 16 (Chr. 16) includes a region of conserved linkage with human Chromosome 21 (Chr. 21). Mouse models of Down syndrome based on trisomy of distal Chr. 16 have several phenotypes similar to those seen in human patients and have proven useful for correlating dosage imbalance of specific genes with specific developmental anomalies. The degree to which such findings can be related to Down syndrome depends on how well the conserved synteny is maintained. Twenty-four genes have been mapped in both species and there are no discordancies, but the region could carry hundreds of genes. Comparative sequence represents the ultimate comparative map and will aid in identification of genes and their regulatory sequences. A physical map of the distal 4.5 Mb of Chr. 16 has been assembled as an essential step toward a map of sequence-ready templates. The map consists of 51 YACs and 15 BACs and includes 18 transcripts, 9 of which are mapped for the first time in mouse, and 3 of which are, for the first time, described in either species. YAC fragmentation was used to precisely localize the 49 markers on the map. Comparison of this physical map with that of the corresponding region on Chr. 21 shows conservation not only of gene order but of size in the 3 Mb from Cbr1 to Ets2; distal to Ets2, the human map is expanded.
Published: 1998

46. Fragmentation and integrative modification of YACs

Author: J W, McKee-Johnson and R H, Reeves
Subjects: Genetic Markers, Recombination, Genetic, Blotting, Southern, Mutagenesis, Insertional, Transformation, Genetic, Genetic Vectors, DNA, Recombinant, Cloning, Molecular, Selection, Genetic, Chromosomes, Artificial, Yeast, Electrophoresis, Gel, Pulsed-Field, Gene Library, Repetitive Sequences, Nucleic Acid
Published: 1996

47. Adjuvant vigabatrin in refractory epilepsy: a ceiling to effective dosage in individual patients?

Author: P. J. W. Mckee, M. J. Brodie, Jackie Blacklaw, GG Thompson, R. A. Gillham, and E. Friel
Subjects: Adult, Male, Adolescent, Placebo, Vigabatrin, Drug Administration Schedule, law.invention, Placebos, Epilepsy, Pharmacotherapy, Randomized controlled trial, Double-Blind Method, law, Statistical significance, medicine, Adjuvant therapy, Humans, Aminocaproates, business.industry, Middle Aged, medicine.disease, Confidence interval, Treatment Outcome, Neurology, Anesthesia, Anticonvulsants, Drug Therapy, Combination, Female, Neurology (clinical), Epilepsies, Partial, business, medicine.drug
Abstract: A double-blind, randomized, cross-over study of additional vigabatrin (gamma-vinyl-GABA, VGB, 1.0 g twice daily for 6 weeks, followed by 1.5 g twice daily for 6 weeks) and matched placebo was undertaken in 24 patients with refractory epilepsy. Nineteen completed the trial satisfactorily. Fewer seizure days were reported during VGB treatment [placebo 41, VGB 23, p < 0.05, 95% confidence interval (CI) -1.5 to -14]. An overall reduction in median seizure numbers failed to reach statistical significance (n = 19; placebo 52, VGB 32, NS, 95% CI -18 to +24). Subgroup analysis, however, showed a significant reduction in partial seizures (n = 17) with 2 g VGB daily (placebo 22, VGB 13, p < 0.05, 95% CI -0.5 to -16.5), but not with higher dosage (placebo 28, VGB 22, NS, 95% CI -18 to +11). A deterioration in control of partial seizures as compared with the equivalent placebo phase was observed when patients were changed from 2 to 3 g/day VGB (2 g VGB 13, 3 g VGB 22, p = 0.05, 95% CI 0 to +20). Loss of efficacy was noted in 3 patients, and seizure control worsened slightly in 5 others. One previously resistant patient developed a therapeutic response, and 2 other patients reported an additional useful reduction in seizures. In the remaining 8 patients, seizure frequency did not change. VGB did not appear to benefit tonic-clonic seizures. Serum VGB concentrations were higher during treatment with 3 g (15.5 +/- 8.9 mg/L) daily than with 2 g (13.5 +/- 11.2 mg/L). No important alterations were noted in the concentrations of concomitantly administered antiepileptic drugs (AEDs) throughout the trial. VGB is useful adjuvant therapy for treatment of partial seizures. There may be a ceiling to effective dosage. This demands individual dose titration for each patient.
Published: 1993

48. Five years of anticonvulsant monitoring on site at the epilepsy clinic

Author: Martin J. Brodie, P. J. W. Mckee, I. W. Percy-Robb, A. F. Brodie, and J. G. Larkin
Subjects: Phenytoin, medicine.medical_specialty, Outpatient Clinics, Hospital, Time Factors, medicine.medical_treatment, Epilepsy, Pharmacokinetics, Internal medicine, medicine, Humans, Pharmacology (medical), Prospective Studies, Pharmacology, biology, business.industry, Valproic Acid, Carbamazepine, biology.organism_classification, medicine.disease, Drug concentration, Anticonvulsant, Scotland, Tasa, Anesthesia, Phenobarbital, Anticonvulsants, Drug Monitoring, business, medicine.drug
Abstract: The influence of antiepileptic drug monitoring on site at the epilepsy clinic was assessed in a prospective way by recording physicians' decisions before and after the drug concentration became available over the five-year period including 1986 to 1990. A total of 2,857 assays (1,121 carbamazepine, 798 phenytoin, 622 sodium valproate, and 72 phenobarbital) were performed during 2,696 hospital attendances on 618 epileptic patients. A gradual reduction in the proportion of visits monitored annually was observed (1986: 42%; 1987: 51%; 1988: 44%; 1989: 39%; 1990: 28%; p0.01). In 481 (17.8%) visits a change in management resulted from knowledge of the drug concentration. This was not an automatic response, as a large minority of unexpected results did not produce such an alteration. The proportion of decisions to adjust the drug dose after an unexpected result, however, tended to increase over the years of the study (1986: 43%; 1987: 70%; 1988: 60%; 1989: 78%; 1990: 54%; p0.01). Changes in anticonvulsant dose following an unexpected result were observed in "low" (59%), "therapeutic" (61%), and "high" (52%) concentration categories. Possible benefit for patients can be inferred from the observation that more assay results fell within the target range in the last (61%) compared with the first (33%) year of monitoring (p0.01).
Published: 1993

49. Managing seizures in the casualty department

Author: J. G. Larkin, Martin J. Brodie, J. A. Dawson, P. J. W. Mckee, and E. A. Wilson
Subjects: Adult, Male, Pediatrics, medicine.medical_specialty, Letter, Adolescent, MEDLINE, Epilepsy, Seizures, medicine, Humans, Child, Referral and Consultation, General Environmental Science, Aged, business.industry, General Engineering, General Medicine, Risk factor (computing), Middle Aged, medicine.disease, Hospitalization, Scotland, Emergency medicine, General Earth and Planetary Sciences, Anticonvulsants, Female, Emergencies, business, Emergency Service, Hospital, Research Article
Published: 1990

50. Myoclonic Epilepsy — Pitfalls in Diagnosis and Management

Author: J. G. Larkin, MartinJ. Brodie, P. J. W. Mckee, and G. McGinn
Subjects: Adult, Male, Phenytoin, Pediatrics, medicine.medical_specialty, Adolescent, Epilepsies, Myoclonic, 030204 cardiovascular system & hematology, Diagnosis, Differential, 03 medical and health sciences, 0302 clinical medicine, Seizures, medicine, Humans, 030212 general & internal medicine, business.industry, Valproic Acid, General Medicine, Carbamazepine, medicine.disease, Adult life, Myoclonic epilepsy, Female, business, medicine.drug
Abstract: Three cases of myoclonic epilepsy presenting in adolescence are described. Seizures were uninfluenced by treatment with carbamazepine. Substitution of sodium valproate in early adult life resulted in all becoming seizure-free. A high degree of clinical awareness is required in making the correct diagnosis and in choosing appropriate therapy for this form of epilepsy which can present with generalised tonic-clonic or partial seizures.
Published: 1991
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Database

Publisher

60 results on '"J W McKee"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources