Search

Your search keyword '"ROMANO, P"' showing total 131 results
Start Over Author "ROMANO, P" Journal monthly notices of the royal astronomical society
131 results on '"ROMANO, P"'

1. Photospheric signatures of CME onset.

Author

Aslam, O P M, MacTaggart, D, Williams, T, Fletcher, L, and Romano, P

Subjects
SOLAR magnetic fields, CORONAL mass ejections, UMPOLUNG, MAGNETIC flux, MAGNETIC fields
Abstract

Coronal mass ejections (CMEs) are solar eruptions that involve large-scale changes to the magnetic topology of an active region. There exists a range of models for CME onset which are based on twisted or sheared magnetic field above a polarity inversion line (PIL). We present observational evidence that topological changes at PILs, in the photosphere, form a key part of CME onset, as implied by many models. In particular, we study the onset of 30 CMEs and investigate topological changes in the photosphere by calculating the magnetic winding flux, using the artop code. By matching the times and locations of winding signatures with CME observations produced by the almanac code, we confirm that these signatures are indeed associated with CMEs. Therefore, as well as presenting evidence that changes in magnetic topology at the photosphere are a common signature of CME onset, our approach also allows for the finding of the source location of a CME within an active region. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

2. NuSTAR detection of a cyclotron line in the supergiant fast X-ray transient IGR J17544−2619

Author

Bhalerao, Varun, Romano, Patrizia, Tomsick, John, Natalucci, Lorenzo, Smith, David M, Bellm, Eric, Boggs, Steven E, Chakrabarty, Deepto, Christensen, Finn E, Craig, William W, Fuerst, Felix, Hailey, Charles J, Harrison, Fiona A, Krivonos, Roman A, Lu, Ting-Ni, Madsen, Kristin, Stern, Daniel, Younes, George, and Zhang, William

Subjects
X-rays: binaries, X-rays: individual: IGR J17544-2619, astro-ph.HE, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

We present NuSTAR spectral and timing studies of the supergiant fast X-ray transient (SFXT) IGR J17544-2619. The spectrum is well described by an ~1 keV blackbody and a hard continuum component, as expected from an accreting X-ray pulsar. We detect a cyclotron line at 17 keV, confirming that the compact object in IGR J17544-2619 is indeed a neutron star. This is the first measurement of the magnetic field in an SFXT. The inferred magnetic field strength, B = (1.45 ± 0.03) × 1012G (1 + z) is typical of neutron stars in X-ray binaries, and rules out a magnetar nature for the compact object. We do not find any significant pulsations in the source on time-scales of 1-2000 s.

Published
2015

6. NuSTAR and Swift observations of two supergiant fast X-ray transients: AX J1841.0−0536 and SAX J1818.6−1703.

Author

Bozzo, E, Ferrigno, C, and Romano, P

Subjects
MAGNETIC flux density, X-rays, NEUTRON stars, STELLAR magnetic fields, CYCLOTRONS, NEUTRON measurement, SMALL-angle X-ray scattering, MAGNETIC fields
Abstract

Supergiant fast X-ray transients are wind-fed binaries hosting neutron star accretors, which display a peculiar variability in the X-ray domain. Different models have been proposed to explain this variability and the strength of the compact object magnetic field is generally considered a key parameter to discriminate among possible scenarios. We present here the analysis of two simultaneous observational campaigns carried out with Swift and NuSTAR targeting the supergiant fast X-ray transient sources AX J1841.0−0536 and SAX J1818.6−1703. A detailed spectral analysis is presented for both sources, with the main goal of hunting for cyclotron resonant scattering features that can provide a direct measurement of the neutron star magnetic field intensity. AX J1841.0−0536 was caught during the observational campaign at a relatively low flux. The source broad-band spectrum was featureless and could be well-described by using a combination of a hot blackbody and a power-law component with no measurable cut-off energy. In the case of SAX J1818.6−1703, the broad-band spectrum presented a relatively complex curvature which could be described by an absorbed cut-off power law (including both a cut-off and a folding energy) and featured a prominent edge at ∼7 keV, compatible with being associated to the presence of a 'screen' of neutral material partly obscuring the X-ray source. The fit to the broad-band spectrum also required the addition of a moderately broad (∼1.6 keV) feature centred at ∼14 keV. If interpreted as a cyclotron resonant scattering feature, our results would indicate for SAX J1818.6−1703 a relatively low-magnetized neutron star (∼1.2 × 1012 G). [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

7. Swift/XRT observations of superorbital modulations in wind-fed supergiant X-ray binaries.

Author

Romano, P, Bozzo, E, Islam, N, and Corbet, R H D

Subjects
*X-ray binaries, *X-ray telescopes, *SOFT X rays, *LIGHT curves, *X-rays, *GAMMA ray bursts
Abstract

We present the first Swift /XRT long-term monitoring of 2S 0114+650, a wind-fed supergiant X-ray binary for which both orbital and superorbital periods are known (P orb ∼ 11.6 d and P sup ∼ 30.8 d). Our campaign, summing up to ∼79 ks, is the most intense and complete sampling of the X-ray light curve of this source with a sensitive pointed X-ray instrument, and covers 17 orbital, and 6 superorbital cycles. The combination of flexibility, sensitivity, and soft X-ray coverage of the X-ray telescope (XRT) allowed us to confirm previously reported spectral changes along the orbital cycle of the source and unveil the variability in its spectral parameters as a function of the superorbital phase. For completeness, we also report on a similar analysis carried out by exploiting XRT archival data on three additional wind-fed supergiant X-ray binaries IGR J16418−4532, IGR J16479−4514, and IGR J16493−4348. For these sources, the archival data provided coverage along several superorbital cycles but our analysis could not reveal any significant spectral variability. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

8. Swift, NuSTAR, and INTEGRAL observations of the symbiotic X-ray binary IGR J16194-2810.

Author

Bozzo, E, Romano, P, Ferrigno, C, and Ducci, L

Subjects
*X-ray binaries, *STELLAR evolution, *NEUTRON stars, *ACCRETION disks, *INTEGRALS, *GAMMA ray bursts
Abstract

We report on a simultaneous observational campaign with both Swift /XRT and NuSTAR targeting the symbiotic X-ray binary (SyXB) IGR J16194-2810. The main goal of the campaign was to investigate the possible presence of cyclotron scattering absorption features in the broad-band spectrum of the source, and help advance our understanding of the process of neutron star formation via the accretion-induced collapse of a white dwarf. The 1–30 keV spectrum of the source, as measured during our campaign, did not reveal the presence of any statistically significant absorption feature. The spectrum could be well described using a model comprising a thermal black-body hot component, most likely emerging from the surface of the accreting neutron star, and a power law with no measurable cut-off energy (and affected by a modest absorption column density). Compared to previous analyses in the literature, we could rule out the presence of a colder thermal component emerging from an accretion disc, compatible with the idea that IGR J16194-2810 is a wind-fed binary (as most of the SyXBs). Our results were strengthened by exploiting the archival XRT and INTEGRAL data, extending the validity of the spectral model used up to 0.3–40 keV and demonstrating that IGR J16194-2810 is unlikely to undergo significant spectral variability over time in the X-ray domain. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

9. Sensitivity of the Cherenkov Telescope Array to TeV photon emission from the Large Magellanic Cloud

Author

Acharyya, A, primary, Adam, R, additional, Aguasca-Cabot, A, additional, Agudo, I, additional, Aguirre-Santaella, A, additional, Alfaro, J, additional, Aloisio, R, additional, Alves Batista, R, additional, Amato, E, additional, Angüner, E O, additional, Aramo, C, additional, Arcaro, C, additional, Asano, K, additional, Aschersleben, J, additional, Ashkar, H, additional, Backes, M, additional, Baktash, A, additional, Balazs, C, additional, Balbo, M, additional, Ballet, J, additional, Bamba, A, additional, Baquero Larriva, A, additional, Barbosa Martins, V, additional, Barres de Almeida, U, additional, Barrio, J A, additional, Bastieri, D, additional, Batista, P, additional, Batkovic, I, additional, Baxter, J R, additional, Becerra González, J, additional, Becker Tjus, J, additional, Benbow, W, additional, Bernardini, E, additional, Bernardos Martín, M I, additional, Bernete Medrano, J, additional, Berti, A, additional, Bertucci, B, additional, Beshley, V, additional, Bhattacharjee, P, additional, Bhattacharyya, S, additional, Bigongiari, C, additional, Biland, A, additional, Bissaldi, E, additional, Bocchino, F, additional, Bordas, P, additional, Borkowski, J, additional, Bottacini, E, additional, Böttcher, M, additional, Bradascio, F, additional, Brown, A M, additional, Bulgarelli, A, additional, Burmistrov, L, additional, Caroff, S, additional, Carosi, A, additional, Carquín, E, additional, Casanova, S, additional, Cascone, E, additional, Cassol, F, additional, Cerruti, M, additional, Chadwick, P, additional, Chaty, S, additional, Chen, A, additional, Chiavassa, A, additional, Chytka, L, additional, Conforti, V, additional, Cortina, J, additional, Costa, A, additional, Costantini, H, additional, Cotter, G, additional, Crestan, S, additional, Cristofari, P, additional, D’Ammando, F, additional, Dalchenko, M, additional, Dazzi, F, additional, De Angelis, A, additional, De Caprio, V, additional, de Gouveia Dal Pino, E M, additional, De Martino, D, additional, de Naurois, M, additional, de Souza, V, additional, del Valle, M V, additional, Delgado Giler, A G, additional, Delgado, C, additional, della Volpe, D, additional, Depaoli, D, additional, Di Girolamo, T, additional, Di Piano, A, additional, Di Pierro, F, additional, Di Tria, R, additional, Di Venere, L, additional, Diebold, S, additional, Doro, M, additional, Dumora, D, additional, Dwarkadas, V V, additional, Eckner, C, additional, Egberts, K, additional, Emery, G, additional, Escudero, J, additional, Falceta-Goncalves, D, additional, Fedorova, E, additional, Fegan, S, additional, Feng, Q, additional, Ferenc, D, additional, Ferrand, G, additional, Fiandrini, E, additional, Filipovic, M, additional, Fioretti, V, additional, Foffano, L, additional, Fontaine, G, additional, Fukui, Y, additional, Gaggero, D, additional, Galanti, G, additional, Galaz, G, additional, Gallozzi, S, additional, Gammaldi, V, additional, Garczarczyk, M, additional, Gasbarra, C, additional, Gasparrini, D, additional, Ghalumyan, A, additional, Giarrusso, M, additional, Giavitto, G, additional, Giglietto, N, additional, Giordano, F, additional, Giuliani, A, additional, Glicenstein, J -F, additional, Goldoni, P, additional, Goulart Coelho, J, additional, Granot, J, additional, Green, D, additional, Green, J G, additional, Grondin, M -H, additional, Gueta, O, additional, Hadasch, D, additional, Hamal, P, additional, Hassan, T, additional, Hayashi, K, additional, Heller, M, additional, Hernández Cadena, S, additional, Hiroshima, N, additional, Hnatyk, B, additional, Hnatyk, R, additional, Hofmann, W, additional, Holder, J, additional, Holler, M, additional, Horan, D, additional, Horvath, P, additional, Hrabovsky, M, additional, Hütten, M, additional, Iarlori, M, additional, Inada, T, additional, Incardona, F, additional, Inoue, S, additional, Iocco, F, additional, Jamrozy, M, additional, Jin, W, additional, Jung-Richardt, I, additional, Juryšek, J, additional, Kantzas, D, additional, Karas, V, additional, Katagiri, H, additional, Kerszberg, D, additional, Knödlseder, J, additional, Komin, N, additional, Kornecki, P, additional, Kosack, K, additional, Kowal, G, additional, Kubo, H, additional, Lamastra, A, additional, Lapington, J, additional, Lemoine-Goumard, M, additional, Lenain, J -P, additional, Leone, F, additional, Leto, G, additional, Leuschner, F, additional, Lindfors, E, additional, Lohse, T, additional, Lombardi, S, additional, Longo, F, additional, López-Coto, R, additional, López-Oramas, A, additional, Loporchio, S, additional, Luque-Escamilla, P L, additional, Macias, O, additional, Majumdar, P, additional, Mandat, D, additional, Mangano, S, additional, Manicò, G, additional, Mariotti, M, additional, Marquez, P, additional, Marsella, G, additional, Martí, J, additional, Martin, P, additional, Martínez, M, additional, Mazin, D, additional, Menchiari, S, additional, Meyer, D M -A, additional, Miceli, D, additional, Miceli, M, additional, Michałowski, J, additional, Mitchell, A, additional, Moderski, R, additional, Mohrmann, L, additional, Molero, M, additional, Molina, E, additional, Montaruli, T, additional, Moralejo, A, additional, Morcuende, D, additional, Morselli, A, additional, Moulin, E, additional, Moya, V, additional, Mukherjee, R, additional, Munari, K, additional, Muraczewski, A, additional, Nagataki, S, additional, Nakamori, T, additional, Nayak, A, additional, Niemiec, J, additional, Nievas, M, additional, Nikołajuk, M, additional, Nishijima, K, additional, Noda, K, additional, Nosek, D, additional, Novosyadlyj, B, additional, Nozaki, S, additional, Ohishi, M, additional, Ohm, S, additional, Okumura, A, additional, Olmi, B, additional, Ong, R A, additional, Orienti, M, additional, Orito, R, additional, Orlandini, M, additional, Orlando, E, additional, Orlando, S, additional, Ostrowski, M, additional, Oya, I, additional, Pagliaro, A, additional, Palatka, M, additional, Pantaleo, F R, additional, Paoletti, R, additional, Paredes, J M, additional, Parmiggiani, N, additional, Patricelli, B, additional, Pech, M, additional, Pecimotika, M, additional, Persic, M, additional, Petruk, O, additional, Pierre, E, additional, Pietropaolo, E, additional, Pirola, G, additional, Pohl, M, additional, Prandini, E, additional, Priyadarshi, C, additional, Pühlhofer, G, additional, Pumo, M L, additional, Punch, M, additional, Queiroz, F S, additional, Quirrenbach, A, additional, Rainò, S, additional, Rando, R, additional, Razzaque, S, additional, Reimer, A, additional, Reimer, O, additional, Reposeur, T, additional, Ribó, M, additional, Richtler, T, additional, Rico, J, additional, Rieger, F, additional, Rigoselli, M, additional, Rizi, V, additional, Roache, E, additional, Rodriguez Fernandez, G, additional, Romano, P, additional, Romeo, G, additional, Rosado, J, additional, Rosales de Leon, A, additional, Rudak, B, additional, Rulten, C, additional, Sadeh, I, additional, Saito, T, additional, Sánchez-Conde, M, additional, Sano, H, additional, Santangelo, A, additional, Santos-Lima, R, additional, Sarkar, S, additional, Saturni, F G, additional, Scherer, A, additional, Schovanek, P, additional, Schussler, F, additional, Schwanke, U, additional, Sergijenko, O, additional, Servillat, M, additional, Siejkowski, H, additional, Siqueira, C, additional, Spencer, S, additional, Stamerra, A, additional, Stanič, S, additional, Steppa, C, additional, Stolarczyk, T, additional, Suda, Y, additional, Tavernier, T, additional, Teshima, M, additional, Tibaldo, L, additional, Torres, D F, additional, Tothill, N, additional, Vacula, M, additional, Vallage, B, additional, Vallania, P, additional, van Eldik, C, additional, Vázquez Acosta, M, additional, Vecchi, M, additional, Ventura, S, additional, Vercellone, S, additional, Viana, A, additional, Vigorito, C F, additional, Vink, J, additional, Vitale, V, additional, Vodeb, V, additional, Vorobiov, S, additional, Vuillaume, T, additional, Wagner, S J, additional, Walter, R, additional, White, M, additional, Wierzcholska, A, additional, Will, M, additional, Yamazaki, R, additional, Yang, L, additional, Yoshikoshi, T, additional, Zacharias, M, additional, Zaharijas, G, additional, Zavrtanik, D, additional, Zavrtanik, M, additional, Zdziarski, A A, additional, Zhdanov, V I, additional, Ziętara, K, additional, and Živec, M, additional

Published
2023
Full Text
View/download PDF

11. symbiotic X-ray binaries Sct X-1, 4U 1700+24, and IGR J17329−2731.

Author

Bozzo, E, Romano, P, Ferrigno, C, and Oskinova, L

Subjects
*X-ray binaries, *NEUTRON stars, *SOFT X rays, *SUPERGIANT stars, *X-rays
Abstract

Symbiotic X-ray binaries are systems hosting a neutron star accreting form the wind of a late-type companion. These are rare objects and so far only a handful of them are known. One of the most puzzling aspects of the symbiotic X-ray binaries is the possibility that they contain strongly magnetized neutron stars. These are expected to be evolutionary much younger compared to their evolved companions and could thus be formed through the (yet poorly known) accretion induced collapse of a white dwarf. In this paper, we perform a broad-band X-ray and soft γ-ray spectroscopy of two known symbiotic binaries, Sct X−1 and 4U 1700+24, looking for the presence of cyclotron scattering features that could confirm the presence of strongly magnetized NSs. We exploited available Chandra ,  Swift , and NuSTAR data. We find no evidence of cyclotron resonant scattering features (CRSFs) in the case of Sct X−1 but in the case of 4U 1700+24 we suggest the presence of a possible CRSF at ∼16 keV and its first harmonic at ∼31 keV, although we could not exclude alternative spectral models for the broad-band fit. If confirmed by future observations, 4U 1700+24 could be the second symbiotic X-ray binary with a highly magnetized accretor. We also report about our long-term monitoring of the last discovered symbiotic X-ray binary IGR J17329−2731 performed with Swift /XRT. The monitoring revealed that, as predicted, in 2017 this object became a persistent and variable source, showing X-ray flares lasting for a few days and intriguing obscuration events that are interpreted in the context of clumpy wind accretion. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

15. The beamed jet and quasar core of the distant blazar 4C 71.07

Author

Raiteri, C M, primary, Villata, M, additional, Carnerero, M I, additional, Acosta-Pulido, J A, additional, Mirzaqulov, D O, additional, Larionov, V M, additional, Romano, P, additional, Vercellone, S, additional, Agudo, I, additional, Arkharov, A A, additional, Bach, U, additional, Bachev, R, additional, Baitieri, S, additional, Borman, G A, additional, Boschin, W, additional, Bozhilov, V, additional, Butuzova, M S, additional, Calcidese, P, additional, Carosati, D, additional, Casadio, C, additional, Chen, W-P, additional, Damljanovic, G, additional, Di Paola, A, additional, Doroshenko, V T, additional, Efimova, N V, additional, Ehgamberdiev, Sh A, additional, Giroletti, M, additional, Gómez, J L, additional, Grishina, T S, additional, Ibryamov, S, additional, Jermak, H, additional, Jorstad, S G, additional, Kimeridze, G N, additional, Klimanov, S A, additional, Kopatskaya, E N, additional, Kurtanidze, O M, additional, Kurtanidze, S O, additional, Lähteenmäki, A, additional, Larionova, E G, additional, Marscher, A P, additional, Mihov, B, additional, Minev, M, additional, Molina, S N, additional, Moody, J W, additional, Morozova, D A, additional, Nazarov, S V, additional, Nikiforova, A A, additional, Nikolashvili, M G, additional, Ovcharov, E, additional, Peneva, S, additional, Righini, S, additional, Rizzi, N, additional, Sadun, A C, additional, Samal, M R, additional, Savchenko, S S, additional, Semkov, E, additional, Sigua, L A, additional, Slavcheva-Mihova, L, additional, Steele, I A, additional, Strigachev, A, additional, Tornikoski, M, additional, Troitskaya, Yu V, additional, Troitsky, I S, additional, and Vince, O, additional

Published
2019
Full Text
View/download PDF

20. The prolonged X-ray flaring activity of Mrk 501 in 2014

Author

Kapanadze, B., primary, Dorner, D., additional, Romano, P., additional, Vercellone, S., additional, Mannheim, K., additional, Lindfors, E., additional, Nilsson, K., additional, Reinthal, R., additional, Takalo, L., additional, Kapanadze, S., additional, and Tabagari, L., additional

Published
2017
Full Text
View/download PDF

21. Evidence for the magnetar nature of 1E 161348−5055 in RCW 103

Author

D'Aì, A., primary, Evans, P. A., additional, Burrows, D. N., additional, Kuin, N. P. M., additional, Kann, D. A., additional, Campana, S., additional, Maselli, A., additional, Romano, P., additional, Cusumano, G., additional, La Parola, V., additional, Barthelmy, S. D., additional, Beardmore, A. P., additional, Cenko, S. B., additional, De Pasquale, M., additional, Gehrels, N., additional, Greiner, J., additional, Kennea, J. A., additional, Klose, S., additional, Melandri, A., additional, Nousek, J. A., additional, Osborne, J. P., additional, Palmer, D. M., additional, Sbarufatti, B., additional, Schady, P., additional, Siegel, M. H., additional, Tagliaferri, G., additional, Yates, R., additional, and Zane, S., additional

Published
2016
Full Text
View/download PDF

22. Putting the hadron beam scenario for extreme blazars to the test with the Cherenkov Telescope Array.

Author

Tavecchio, F, Romano, P, Landoni, M, and Vercellone, S

Subjects
*HADRON beams, *BL Lacertae objects, *CHERENKOV radiation, *COMPUTER simulation, *GAMMA ray sources
Abstract

Hadron beams are invoked to explain the peculiar properties of a subclass of BL Lac objects, the so-called extreme BL Lacs (EHBLs). This scenario predicts a quite distinctive feature for the high-energy gamma-ray spectrum of these sources, namely a hard energy tail extending up to ∼100 TeV. It has been proposed that the detection of this tail can offer an unambiguous way to distinguish between the hadron beam scenario and the standard one, which instead assumes gamma-ray emission from the jet strongly depleted at the highest energies (E > 30 TeV) because of the interaction with the optical-IR cosmic radiation field. We present dedicated simulations of observations through the presently under construction Cherenkov Telescope Array (CTA) of the very high energy spectrum of the prototypical EHBL 1ES 0229+200 assuming the two alternative models. We demonstrate that, considering 50 h of observations from the southern site of CTA (the most sensitive at the highest energies), in the case of the hadron beam model it is possible to detect the source up to 100 TeV. This, together with the non-detection of the source above 10 TeV in the standard case, ensures that CTA observations can be effectively used to unambiguously confirm or rule out the hadron beam scenario. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

24. The second strong X-ray flare and multifrequency variability of 1ES 1959+650 in 2016 January–August.

Author

Kapanadze, B., Dorner, D., Vercellone, S., Romano, P., Hughes, P., Aller, M., Aller, H., Reynolds, M., Kapanadze, S., and Tabagari, L.

Subjects
ACTIVE galaxies, X-ray telescopes, SPACE telescopes, BL Lacertae objects, RADIO sources (Astronomy)
Abstract

The X-ray variability of the BL Lacertae source 1ES 1959+650 was studied intensively with X-ray telescope (XRT) onboard Swift during 2016 January-August. In this paper, we present the results obtained during this campaign. A long-term high X-ray state was superimposed by shorter-term flares by a factor of 1.9-4.7.We found 35 instances of intra-day variability which showed very fast flux changes by 14-21 per cent occurring within 1 ks and a decline by a factor of 2.3 in 17.2 ks. Similarly to the previous years, this period sometimes was characterized by a lack of correlated X-ray and TeV variability, indicating that the high-energy emission in 1ES 1959+650 was generated in the emission region more complex than a single zone. The source showed a significant X-ray - high-energy flux correlation, while the former was not correlated with the optical-UV fluxes. The best fits of the 0.3-10 keV spectra were mainly obtained using the log-parabola model. Strong spectral variability was detected, shifting the peak of the spectral energy distribution by more than 10 keV that happens rarely in blazars. During some strong short-term flares, the photon index at 1 keV frequently became harder than 1.70, and the spectral evolution was characterized by a harder-when-brighter behaviour. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

26. Broad-band monitoring tracing the evolution of the jet and disc in the black hole candidate X-ray binary MAXI J1659−152

Author

van der Horst, A. J., primary, Curran, P. A., additional, Miller-Jones, J. C. A., additional, Linford, J. D., additional, Gorosabel, J., additional, Russell, D. M., additional, de Ugarte Postigo, A., additional, Lundgren, A. A., additional, Taylor, G. B., additional, Maitra, D., additional, Guziy, S., additional, Belloni, T. M., additional, Kouveliotou, C., additional, Jonker, P. G., additional, Kamble, A., additional, Paragi, Z., additional, Homan, J., additional, Kuulkers, E., additional, Granot, J., additional, Altamirano, D., additional, Buxton, M. M., additional, Castro-Tirado, A., additional, Fender, R. P., additional, Garrett, M. A., additional, Gehrels, N., additional, Hartmann, D. H., additional, Kennea, J. A., additional, Krimm, H. A., additional, Mangano, V., additional, Ramirez-Ruiz, E., additional, Romano, P., additional, Wijers, R. A. M. J., additional, Wijnands, R., additional, and Yang, Y. J., additional

Published
2013
Full Text
View/download PDF

27. Long-term monitoring of PKS 0537−441 with Fermi–LAT and multiwavelength observations

Author

D’Ammando, F., primary, Antolini, E., additional, Tosti, G., additional, Finke, J., additional, Ciprini, S., additional, Larsson, S., additional, Ajello, M., additional, Covino, S., additional, Gasparrini, D., additional, Gurwell, M., additional, Hauser, M., additional, Romano, P., additional, Schinzel, F., additional, Wagner, S. J., additional, Impiombato, D., additional, Perri, M., additional, Persic, M., additional, Pian, E., additional, Polenta, G., additional, Sbarufatti, B., additional, Treves, A., additional, Vercellone, S., additional, Wehrle, A., additional, and Zook, A., additional

Published
2013
Full Text
View/download PDF

28. Evidence for the magnetar nature of 1E 161348-5055 in RCW 103.

Author

D'ì, A., Evans, P. A., Burrows, D. N., Kuin, N. P. M., Kann, D. A., Campana, S., Maselli, A., Romano, P., Cusumano, G., Parola, V. La, Barthelmy, S. D., Beardmore, A. P., Cenko, S. B., De Pasquale, M., Gehrels, N., Greiner, J., Kennea, J. A., Klose, S., Melandri, A., and Nousek, J. A.

Subjects
X-ray astronomy, SPACE telescopes, NEAR infrared radiation, ORBITAL mechanics, NEUTRONS, STELLAR luminosity function
Abstract

We report on the detection of a bright, short, structured X-ray burst coming from the supernova remnant RCW 103 on 2016 June 22 caught by the Swift/Burst Alert Telescope (BAT) monitor, and on the follow-up campaign made with Swift/X-ray Telescope, Swift/UV/Optical Telescope, and the optical/near-infrared (NIR) Gamma-Ray burst Optical and Near-infrared Detector. The characteristics of this flash, such as duration and spectral shape, are consistent with typical short bursts observed from soft gamma repeaters. The BAT error circle at 68 per cent confidence range encloses the point-like X-ray source at the centre of the nebula, 1E 161348-5055. Its nature has been long debated due to a periodicity of 6.67 h in X-rays, which could indicate either an extremely slow pulsating neutron star, or the orbital period of a very compact X-ray binary system. We found that 20 min before the BAT trigger, the soft X-ray emission of 1E 161348-5055 was a factor of ~100 higher than measured 2 yr earlier, indicating that an outburst had already started. By comparing the spectral and timing characteristics of the source in the 2 yr before the outburst and after the BAT event, we find that, besides a change in luminosity and spectral shape, also the 6.67 h pulsed profile has significantly changed with a clear phase shift with respect to its low-flux profile. The UV/optical/NIR observations did not reveal any counterpart at the position of 1E 161348-5055. Based on these findings, we associate the BAT burst with 1E 161348-5055, we classify it as a magnetar, and pinpoint the 6.67 h periodicity as the magnetar spin period. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

29. The long-term Swift observations of the high-energy peaked BL Lacertae source 1ES 1959+650.

Author

Kapanadze, B., Romano, P., Vercellone, S., Kapanadze, S., Mdzinarishvili, T., and Kharshiladze, G.

Subjects
*SPECTRAL energy distribution, *SPECTRUM analysis, *MOMENTS method (Statistics), *RADIATION, *QUALITATIVE chemical analysis
Abstract

We present the results based on the monitoring of the high-energy peaked BL Lacertae object 1ES 1959+650 by the Swift satellite during 2005-2014. Our timing study shows that the source was highly variable on longer (weeks-to-months) time-scales with the 0.3-10 keV fluxes ranging by a factor of 8. It sometimes showed a significant intra-day variability in the course of ~1 ks, detected mainly in the epochs of higher brightness states. The flux variability exhibited an erratic character and no signatures of periodic variations are revealed. The X-ray spectra were mainly curved with broad ranges of photon index, curvature parameter, hardness ratio, synchrotron spectral energy distribution (SED) peak location which exhibited a significant variability with the flux at different time-scales. Our study of multi-wavelength cross-correlations shows that the one-zone synchrotron self-Compton scenario was not always valid for 1ES 1959+650. The X-ray flares were sometimes not accompanied with an increasing activity in the γ -ray or lower-energy parts of the spectrum and vice versa. Similar to the prominent 'orphan' TeV event in 2002, significant flares in the high-energy and very high energy bands in 2009 May and 2012 May were not accompanied by those in the synchrotron part of the spectrum. Similar to other TeV-detected high-energy peaked BLLs, the stochastic acceleration of the electrons from the magnetic turbulence close to the shock front may be more important for our target compared to other scenarios since it showed mainly broader synchrotron SEDs during the X-ray flares expected when the stochastic mechanism is more efficient. [ABSTRACT FROM AUTHOR]

Published
2016
Full Text
View/download PDF

31. X-ray and radio observations of the magnetar Swift J1834.9−0846 and its dust-scattering halo

Author

Esposito, P., primary, Tiengo, A., additional, Rea, N., additional, Turolla, R., additional, Fenzi, A., additional, Giuliani, A., additional, Israel, G. L., additional, Zane, S., additional, Mereghetti, S., additional, Possenti, A., additional, Burgay, M., additional, Stella, L., additional, Götz, D., additional, Perna, R., additional, Mignani, R. P., additional, and Romano, P., additional

Published
2013
Full Text
View/download PDF

32. The prompt-afterglow connection in gamma-ray bursts: a comprehensive statistical analysis of Swift X-ray light curves

Author

Margutti, R., primary, Zaninoni, E., additional, Bernardini, M. G., additional, Chincarini, G., additional, Pasotti, F., additional, Guidorzi, C., additional, Angelini, L., additional, Burrows, D. N., additional, Capalbi, M., additional, Evans, P. A., additional, Gehrels, N., additional, Kennea, J., additional, Mangano, V., additional, Moretti, A., additional, Nousek, J., additional, Osborne, J. P., additional, Page, K. L., additional, Perri, M., additional, Racusin, J., additional, Romano, P., additional, Sbarufatti, B., additional, Stafford, S., additional, and Stamatikos, M., additional

Published
2012
Full Text
View/download PDF

36. Long-term spectral and timing properties of the soft gamma-ray repeater SGR 1833−0832 and detection of extended X-ray emission around the radio pulsar PSR B1830−08

Author

Esposito, P., primary, Israel, G. L., additional, Turolla, R., additional, Mattana, F., additional, Tiengo, A., additional, Possenti, A., additional, Zane, S., additional, Rea, N., additional, Burgay, M., additional, Götz, D., additional, Mereghetti, S., additional, Stella, L., additional, Wieringa, M. H., additional, Sarkissian, J. M., additional, Enoto, T., additional, Romano, P., additional, Sakamoto, T., additional, Nakagawa, Y. E., additional, Makishima, K., additional, Nakazawa, K., additional, Nishioka, H., additional, and François-Martin, C., additional

Published
2011
Full Text
View/download PDF

37. The 2008 October Swift detection of X-ray bursts/outburst from the transient SGR-like AXP 1E 1547.0−5408

Author

Israel, G. L., primary, Esposito, P., additional, Rea, N., additional, Dall'Osso, S., additional, Senziani, F., additional, Romano, P., additional, Mangano, V., additional, Götz, D., additional, Zane, S., additional, Tiengo, A., additional, Palmer, D. M., additional, Krimm, H., additional, Gehrels, N., additional, Mereghetti, S., additional, Stella, L., additional, Turolla, R., additional, Campana, S., additional, Perna, R., additional, Angelini, L., additional, and De Luca, A., additional

Published
2010
Full Text
View/download PDF

38. Two years of monitoring supergiant fast X-ray transients with Swift

Author

Romano, P., primary, La Parola, V., additional, Vercellone, S., additional, Cusumano, G., additional, Sidoli, L., additional, Krimm, H. A., additional, Pagani, C., additional, Esposito, P., additional, Hoversten, E. A., additional, Kennea, J. A., additional, Page, K. L., additional, Burrows, D. N., additional, and Gehrels, N., additional

Published
2010
Full Text
View/download PDF

39. Unveiling the origin of X-ray flares in gamma-ray bursts

Author

Chincarini, G., primary, Mao, J., additional, Margutti, R., additional, Bernardini, M. G., additional, Guidorzi, C., additional, Pasotti, F., additional, Giannios, D., additional, Valle, M. Della, additional, Moretti, A., additional, Romano, P., additional, D'Avanzo, P., additional, Cusumano, G., additional, and Giommi, P., additional

Published
2010
Full Text
View/download PDF

40. Early X-ray and optical observations of the soft gamma-ray repeater SGR 0418+5729

Author

Esposito, P., primary, Israel, G. L., additional, Turolla, R., additional, Tiengo, A., additional, Götz, D., additional, De Luca, A., additional, Mignani, R. P., additional, Zane, S., additional, Rea, N., additional, Testa, V., additional, Caraveo, P. A., additional, Chaty, S., additional, Mattana, F., additional, Mereghetti, S., additional, Pellizzoni, A., additional, and Romano, P., additional

Published
2010
Full Text
View/download PDF

44. Monitoring supergiant fast X-ray transients withSwift: results from the first year

Author

Romano, P., primary, Sidoli, L., additional, Cusumano, G., additional, La Parola, V., additional, Vercellone, S., additional, Pagani, C., additional, Ducci, L., additional, Mangano, V., additional, Cummings, J., additional, Krimm, H. A., additional, Guidorzi, C., additional, Kennea, J. A., additional, Hoversten, E. A., additional, Burrows, D. N., additional, and Gehrels, N., additional

Published
2009
Full Text
View/download PDF

47. Methods and results of an automatic analysis of a complete sample ofSwift-XRT observations of GRBs

Author

Evans, P. A., primary, Beardmore, A. P., additional, Page, K. L., additional, Osborne, J. P., additional, O'Brien, P. T., additional, Willingale, R., additional, Starling, R. L. C., additional, Burrows, D. N., additional, Godet, O., additional, Vetere, L., additional, Racusin, J., additional, Goad, M. R., additional, Wiersema, K., additional, Angelini, L., additional, Capalbi, M., additional, Chincarini, G., additional, Gehrels, N., additional, Kennea, J. A., additional, Margutti, R., additional, Morris, D. C., additional, Mountford, C. J., additional, Pagani, C., additional, Perri, M., additional, Romano, P., additional, and Tanvir, N., additional

Published
2009
Full Text
View/download PDF

48. Multiple flaring activity in the supergiant fast X-ray transient IGR J08408−4503 observed withSwift

Author

Romano, P., primary, Sidoli, L., additional, Cusumano, G., additional, Evans, P. A., additional, Ducci, L., additional, Krimm, H. A., additional, Vercellone, S., additional, Page, K. L., additional, Beardmore, A. P., additional, Burrows, D. N., additional, Kennea, J. A., additional, Gehrels, N., additional, La Parola, V., additional, and Mangano, V., additional

Published
2009
Full Text
View/download PDF

49. The complex light curve of the afterglow of GRB071010A

Author

Covino, S., primary, D'Avanzo, P., additional, Klotz, A., additional, Perley, D. A., additional, Amati, L., additional, Campana, S., additional, Chincarini, G., additional, Cucchiara, A., additional, D'Elia, V., additional, Guetta, D., additional, Guidorzi, C., additional, Kann, D. A., additional, Kpc Yolda, A., additional, Misra, K., additional, Olofsson, G., additional, Tagliaferri, G., additional, Antonelli, L. A., additional, Berger, E., additional, Bloom, J. S., additional, Ber, M., additional, Clemens, C., additional, D'Alessio, F., additional, Della Valle, M., additional, di Serego Alighieri, S., additional, Filippenko, A. V., additional, Foley, R. J., additional, Fox, D. B., additional, Fugazza, D., additional, Fynbo, J., additional, Gendre, B., additional, Goldoni, P., additional, Greiner, J., additional, Kocevksi, D., additional, Maiorano, E., additional, Masetti, N., additional, Meurs, E., additional, Modjaz, M., additional, Molinari, E., additional, Moretti, A., additional, Palazzi, E., additional, Pandey, S. B., additional, Piranomonte, S., additional, Poznanski, D., additional, Primak, N., additional, Romano, P., additional, Rossi, E., additional, Roy, R., additional, Silverman, J. M., additional, Stella, L., additional, Stratta, G., additional, Testa, V., additional, Vergani, S. D., additional, Vitali, F., additional, and Zerbi, F., additional

Published
2008
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results