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1. First Very Long Baseline Interferometry Detections at 870{\mu}m

Author

Raymond, Alexander W., Doeleman, Sheperd S., Asada, Keiichi, Blackburn, Lindy, Bower, Geoffrey C., Bremer, Michael, Broguiere, Dominique, Chen, Ming-Tang, Crew, Geoffrey B., Dornbusch, Sven, Fish, Vincent L., García, Roberto, Gentaz, Olivier, Goddi, Ciriaco, Han, Chih-Chiang, Hecht, Michael H., Huang, Yau-De, Janssen, Michael, Keating, Garrett K., Koay, Jun Yi, Krichbaum, Thomas P., Lo, Wen-Ping, Matsushita, Satoki, Matthews, Lynn D., Moran, James M., Norton, Timothy J., Patel, Nimesh, Pesce, Dominic W., Ramakrishnan, Venkatessh, Rottmann, Helge, Roy, Alan L., Sánchez, Salvador, Tilanus, Remo P. J., Titus, Michael, Torne, Pablo, Wagner, Jan, Weintroub, Jonathan, Wielgus, Maciek, Young, André, Akiyama, Kazunori, Albentosa-Ruíz, Ezequiel, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Azulay, Rebecca, Bach, Uwe, Baczko, Anne-Kathrin, Ball, David, Baloković, Mislav, Bandyopadhyay, Bidisha, Barrett, John, Bauböck, Michi, Benson, Bradford A., Bintley, Dan, Blundell, Raymond, Bouman, Katherine L., Boyce, Hope, Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Bronzwaer, Thomas, Bustamante, Sandra, Carlstrom, John E., Chael, Andrew, Chan, Chi-kwan, Chang, Dominic O., Chatterjee, Koushik, Chatterjee, Shami, Chen, Yongjun, Cheng, Xiaopeng, Cho, Ilje, Christian, Pierre, Conroy, Nicholas S., Conway, John E., Crawford, Thomas M., Cruz-Osorio, Alejandro, Cui, Yuzhu, Dahale, Rohan, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Dexter, Jason, Dhruv, Vedant, Dihingia, Indu K., Dzib, Sergio A., Eatough, Ralph P., Emami, Razieh, Falcke, Heino, Farah, Joseph, Fomalont, Edward, Fontana, Anne-Laure, Ford, H. Alyson, Foschi, Marianna, Fraga-Encinas, Raquel, Freeman, William T., Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, Gammie, Charles F., Georgiev, Boris, Gold, Roman, Gómez-Ruiz, Arturo I., Gómez, José L., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Hesper, Ronald, Heumann, Dirk, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Impellizzeri, C. M. Violette, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Jeter, Britton, Jiang, Wu, Jiménez-Rosales, Alejandra, Johnson, Michael D., Jorstad, Svetlana, Jones, Adam C., Joshi, Abhishek V., Jung, Taehyun, Karuppusamy, Ramesh, Kawashima, Tomohisa, Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Kocherlakota, Prashant, Kofuji, Yutaro, Koch, Patrick M., Koyama, Shoko, Kramer, Carsten, Kramer, Joana A., Kramer, Michael, Kubo, Derek, Kuo, Cheng-Yu, La Bella, Noemi, Lee, Sang-Sung, Levis, Aviad, Li, Zhiyuan, Lico, Rocco, Lindahl, Greg, Lindqvist, Michael, Lisakov, Mikhail, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin J., Lowitz, Amy E., Lu, Ru-Sen, MacDonald, Nicholas R., Mahieu, Sylvain, Maier, Doris, Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Martí-Vidal, Iván, Medeiros, Lia, Menten, Karl M., Mizuno, Izumi, Mizuno, Yosuke, Montgomery, Joshua, Moriyama, Kotaro, Moscibrodzka, Monika, Mulaudzi, Wanga, Müller, Cornelia, Müller, Hendrik, Mus, Alejandro, Musoke, Gibwa, Myserlis, Ioannis, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Fuentes, Santiago Navarro, Neilsen, Joey, Ni, Chunchong, Nowak, Michael A., Oh, Junghwan, Okino, Hiroki, Sánchez, Héctor Raúl Olivares, Oyama, Tomoaki, Özel, Feryal, Palumbo, Daniel C. M., Paraschos, Georgios Filippos, Park, Jongho, Parsons, Harriet, Pen, Ue-Li, Piétu, Vincent, PopStefanija, Aleksandar, Porth, Oliver, Prather, Ben, Principe, Giacomo, Psaltis, Dimitrios, Pu, Hung-Yi, Raffin, Philippe A., Rao, Ramprasad, Rawlings, Mark G., Ricarte, Angelo, Ripperda, Bart, Roelofs, Freek, Romero-Cañizales, Cristina, Ros, Eduardo, Roshanineshat, Arash, Ruiz, Ignacio, Ruszczyk, Chet, Rygl, Kazi L. J., Sánchez-Argüelles, David, Sánchez-Portal, Miguel, Sasada, Mahito, Satapathy, Kaushik, Savolainen, Tuomas, Schloerb, F. Peter, Schonfeld, Jonathan, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Salas, León David Sosapanta, Souccar, Kamal, Srinivasan, Ranjani, Stanway, Joshua S., Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Toma, Kenji, Toscano, Teresa, Traianou, Efthalia, Trent, Tyler, Trippe, Sascha, Turk, Matthew, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Vos, Jesse, Ward-Thompson, Derek, Wardle, John, Washington, Jasmin E., Wharton, Robert, Wiik, Kaj, Witzel, Gunther, Wondrak, Michael F., Wong, George N., Wu, Qingwen, Yadlapalli, Nitika, Yamaguchi, Paul, Yfantis, Aristomenis, Yoon, Doosoo, Younsi, Ziri, Yu, Wei, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhang, Shuo, Zhao, Guang-Yao, and Zhao, Shan-Shan

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

The first very long baseline interferometry (VLBI) detections at 870$\mu$m wavelength (345$\,$GHz frequency) are reported, achieving the highest diffraction-limited angular resolution yet obtained from the surface of the Earth, and the highest-frequency example of the VLBI technique to date. These include strong detections for multiple sources observed on inter-continental baselines between telescopes in Chile, Hawaii, and Spain, obtained during observations in October 2018. The longest-baseline detections approach 11$\,$G$\lambda$ corresponding to an angular resolution, or fringe spacing, of 19$\mu$as. The Allan deviation of the visibility phase at 870$\mu$m is comparable to that at 1.3$\,$mm on the relevant integration time scales between 2 and 100$\,$s. The detections confirm that the sensitivity and signal chain stability of stations in the Event Horizon Telescope (EHT) array are suitable for VLBI observations at 870$\mu$m. Operation at this short wavelength, combined with anticipated enhancements of the EHT, will lead to a unique high angular resolution instrument for black hole studies, capable of resolving the event horizons of supermassive black holes in both space and time., Comment: Corresponding author: S. Doeleman

Published
2024
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2. A search for pulsars around Sgr A* in the first Event Horizon Telescope dataset

Author

Torne, Pablo, Liu, Kuo, Eatough, Ralph P., Wongphechauxsorn, Jompoj, Cordes, James M., Desvignes, Gregory, De Laurentis, Mariafelicia, Kramer, Michael, Ransom, Scott M., Chatterjee, Shami, Wharton, Robert, Karuppusamy, Ramesh, Blackburn, Lindy, Janssen, Michael, Chan, Chi-kwan, Crew, Geoffrey B., Matthews, Lynn D., Goddi, Ciriaco, Rottmann, Helge, Wagner, Jan, Sanchez, Salvador, Ruiz, Ignacio, Abbate, Federico, Bower, Geoffrey C., Salamanca, Juan J., Gomez-Ruiz, Arturo I., Herrera-Aguilar, Alfredo, Jiang, Wu, Lu, Ru-Sen, Pen, Ue-Li, Raymond, Alexander W., Shao, Lijing, Shen, Zhiqiang, Paubert, Gabriel, Sanchez-Portal, Miguel, Kramer, Carsten, Castillo, Manuel, Navarro, Santiago, John, David, Schuster, Karl-Friedrich, Johnson, Michael D., Rygl, Kazi L. J., Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Bach, Uwe, Baczko, Anne-Kathrin, Ball, David, Balokovic, Mislav, Barrett, John, Bauboeck, Michi, Benson, Bradford A., Bintley, Dan, Blundell, Raymond, Bouman, Katherine L., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguiere, Dominique, Bronzwaer, Thomas, Bustamante, Sandra, Byun, Do-Young, Carlstrom, John E., Ceccobello, Chiara, Chael, Andrew, Chang, Dominic O., Chatterjee, Koushik, Chen, Ming-Tang, Chen, Yongjun, Cheng, Xiaopeng, Cho, Ilje, Christian, Pierre, Conroy, Nicholas S., Conway, John E., Crawford, Thomas M., Cruz-Osorio, Alejandro, Cui, Yuzhu, Dahale, Rohan, Davelaar, Jordy, Deane, Roger, Dempsey, Jessica, Dexter, Jason, Dhruv, Vedant, Doeleman, Sheperd S., Dougal, Sean, Dzib, Sergio A., Emami, Razieh, Falcke, Heino, Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Ford, H. Alyson, Foschi, Marianna, Fraga-Encinas, Raquel, Freeman, William T., Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, Gammie, Charles F., Garcia, Roberto, Gentaz, Olivier, Georgiev, Boris, Gold, Roman, Gomez, Jose L., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Haworth, Kari, Hecht, Michael H., Hesper, Ronald, Heumann, Dirk, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Impellizzeri, C. M. Violette, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Jeter, Britton, Jimenez-Rosales, Alejandra, Jorstad, Svetlana, Joshi, Abhishek V., Jung, Taehyun, Karami, Mansour, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kocherlakota, Prashant, Kofuji, Yutaro, Koyama, Shoko, Krichbaum, Thomas P., Kuo, Cheng-Yu, La Bella, Noemi, Lauer, Tod R., Lee, Daeyoung, Lee, Sang-Sung, Leung, Po Kin, Levis, Aviad, Li, Zhiyuan, Lico, Rocco, Lindahl, Greg, Lindqvist, Michael, Lisakov, Mikhail, Liu, Jun, Liuzzo, Elisabetta, Lo, Wen-Ping, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin J., MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Marti-Vidal, Ivan, Matsushita, Satoki, Medeiros, Lia, Menten, Karl M., Michalik, Daniel, Mizuno, Izumi, Mizuno, Yosuke, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Muller, Cornelia, Muller, Hendrik, Mus, Alejandro, Musoke, Gibwa, Myserlis, Ioannis, Nadolski, Andrew, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayan, Ramesh, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Neilsen, Joey, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Oh, Junghwan, Okino, Hiroki, Olivares, Hector, Ortiz-Leon, Gisela N., Oyama, Tomoaki, Ozel, Feryal, Palumbo, Daniel C. M., Paraschos, Georgios Filippos, Park, Jongho, Parsons, Harriet, Patel, Nimesh, Pesce, Dominic W., Pietu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Potzl, Felix M., Prather, Ben, Preciado-Lopez, Jorge A., Psaltis, Dimitrios, Pu, Hung-Yi, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Rezzolla, Luciano, Ricarte, Angelo, Ripperda, Bart, Roelofs, Freek, Rogers, Alan, Ros, Eduardo, Romero-Cañizales, Cristina, Roshanineshat, Arash, Roy, Alan L., Ruszczyk, Chet, Sanchez-Arguelles, David, Sasada, Mahito, Satapathy, Kaushik, Savolainen, Tuomas, Schloerb, F. Peter, Schonfeld, Jonathan, Small, Des, Sohn, Bong Won, SooHoo, Jason, Souccar, Kamal, Sun, He, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Toscano, Teresa, Traianou, Efthalia, Trent, Tyler, Trippe, Sascha, Turk, Matthew, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Vos, Jesse, Ward-Thompson, Derek, Wardle, John, Weintroub, Jonathan, Wex, Norbert, Wielgus, Maciek, Wiik, Kaj, Witzel, Gunther, Wondrak, Michael F., Wong, George N., Wu, Qingwen, Yadlapalli, Nitika, Yamaguchi, Paul, Yfantis, Aristomenis, Yoon, Doosoo, Young, Andre, Young, Ken, Younsi, Ziri, Yu, Wei, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhang, Shuo, Zhao, Guang-Yao, and Zhao, Shan-Shan

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The Event Horizon Telescope (EHT) observed in 2017 the supermassive black hole at the center of the Milky Way, Sagittarius A* (Sgr A*), at a frequency of 228.1 GHz ($\lambda$=1.3 mm). The fundamental physics tests that even a single pulsar orbiting Sgr A* would enable motivate searching for pulsars in EHT datasets. The high observing frequency means that pulsars - which typically exhibit steep emission spectra - are expected to be very faint. However, it also negates pulse scattering, an effect that could hinder pulsar detections in the Galactic Center. Additionally, magnetars or a secondary inverse Compton emission could be stronger at millimeter wavelengths than at lower frequencies. We present a search for pulsars close to Sgr A* using the data from the three most-sensitive stations in the EHT 2017 campaign: the Atacama Large Millimeter/submillimeter Array, the Large Millimeter Telescope and the IRAM 30 m Telescope. We apply three detection methods based on Fourier-domain analysis, the Fast-Folding-Algorithm and single pulse search targeting both pulsars and burst-like transient emission; using the simultaneity of the observations to confirm potential candidates. No new pulsars or significant bursts were found. Being the first pulsar search ever carried out at such high radio frequencies, we detail our analysis methods and give a detailed estimation of the sensitivity of the search. We conclude that the EHT 2017 observations are only sensitive to a small fraction ($\lesssim$2.2%) of the pulsars that may exist close to Sgr A*, motivating further searches for fainter pulsars in the region., Comment: 33 pages, 7 figures, 6 Tables. Accepted for publication in ApJ

Published
2023

4. The Greenland Telescope: Construction, Commissioning, and Operations in Pituffik

Author

Chen, Ming-Tang, Asada, Keiichi, Matsushita, Satoki, Raffin, Philippe, Inoue, Makoto, Ho, Paul T. P., Han, Chih-Chiang, Kubo, Derek, Norton, Timothy, Patel, Nimesh A., Nystrom, George, Huang, Chih-Wei L., Martin-Cocher, Pierre, Koay, Jun Yi, Romero-Cañizales, Cristina, Liu, Ching-Tang, Huang, Teddy, Liu, Kuan-Yu, Wei, Tashun, Chang, Shu-Hao, Chilson, Ryan, Oshiro, Peter, Jiang, Homin, Li, Chao-Te, Bower, Geoffrey, Shaw, Paul, Nishioka, Hiroaki, Koch, Patrick M., Chen, Chung-Cheng, Srinivasan, Ranjani, Rao, Ramprasad, Snow, William, Jinchi, Hao, Han, Kuo-Chang, Chang, Song-Chu, Lu, Li-Ming, Ogawa, Hideo, Kimura, Kimihiro, Hasegawa, Yutaka, Pu, Hung-Yi, Koyama, Shoko, Nakamura, Masanori, Bintley, Daniel, Walther, Craig, Friberg, Per, Dempsey, Jessica, Sriharan, T. K., Srikanth, Sivasankaran, Doeleman, Sheperd S., Brissenden, Roger, Marcos, Juan-Carlos Algaba, Jeter, Britt, Kuo, Cheng-Yu, and Park, Jongho

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

In 2018, the Greenland Telescope (GLT) started scientific observation in Greenland. Since then, we have completed several significant improvements and added new capabilities to the telescope system. This paper presents a full review of the GLT system, a summary of our observation activities since 2018, the lessons learned from the operations in the Arctic regions, and the prospect of the telescope., Comment: 26 pages, 11 figures, and 8 tables. This is the version of the article before publication editing, as submitted by an author to Publications of the Astronomical Society of the Pacific. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record will be added when it becomes available

Published
2023

5. WTO must complete an ambitious fisheries subsidies agreement

Author

Sumaila, U. Rashid, Alam, Lubna, Abdallah, Patrizia R., Aheto, Denis, Akintola, Shehu L., Alger, Justin, Andreoli, Vania, Bailey, Megan, Barnes, Colin, Ben-Hasan, Abdulrahman, Brooks, Cassandra M., Carvalho, Adriana R., Cheung, William W. L., Cisneros-Montemayor, Andrés M., Dempsey, Jessica, Halim, Sharina A., Hilmi, Nathalie, Ilori, Matthew O., Jacquet, Jennifer, Karuaihe, Selma T., Le Billon, Philippe, Leape, James, Martin, Tara G., Meeuwig, Jessica J., Micheli, Fiorenza, Mokhtar, Mazlin, Naylor, Rosamond L., Obura, David, Palomares, Maria L. D., Pereira, Laura M., Rogers, Abbie A., Sequeira, Ana M. M., Sogbanmu, Temitope O., Villasante, Sebastian, Zeller, Dirk, and Pauly, Daniel

Published
2024
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6. A ring-like accretion structure in M87 connecting its black hole and jet

Author

Lu, Ru-Sen, Asada, Keiichi, Krichbaum, Thomas P., Park, Jongho, Tazaki, Fumie, Pu, Hung-Yi, Nakamura, Masanori, Lobanov, Andrei, Hada, Kazuhiro, Akiyama, Kazunori, Kim, Jae-Young, Marti-Vidal, Ivan, Gómez, José L., Kawashima, Tomohisa, Yuan, Feng, Ros, Eduardo, Alef, Walter, Britzen, Silke, Bremer, Michael, Broderick, Avery E., Doi, Akihiro, Giovannini, Gabriele, Giroletti, Marcello, Ho, Paul T. P., Honma, Mareki, Hughes, David H., Inoue, Makoto, Jiang, Wu, Kino, Motoki, Koyama, Shoko, Lindqvist, Michael, Liu, Jun, Marscher, Alan P., Matsushita, Satoki, Nagai, Hiroshi, Rottmann, Helge, Savolainen, Tuomas, Schuster, Karl-Friedrich, Shen, Zhi-Qiang, de Vicente, Pablo, Walker, R. Craig, Yang, Hai, Zensus, J. Anton, Algaba, Juan Carlos, Allardi, Alexander, Bach, Uwe, Berthold, Ryan, Bintley, Dan, Byun, Do-Young, Casadio, Carolina, Chang, Shu-Hao, Chang, Chih-Cheng, Chang, Song-Chu, Chen, Chung-Chen, Chen, Ming-Tang, Chilson, Ryan, Chuter, Tim C., Conway, John, Crew, Geoffrey B., Dempsey, Jessica T., Dornbusch, Sven, Faber, Aaron, Friberg, Per, García, Javier González, Garrido, Miguel Gómez, Han, Chih-Chiang, Han, Kuo-Chang, Hasegawa, Yutaka, Herrero-Illana, Ruben, Huang, Yau-De, Huang, Chih-Wei L., Impellizzeri, Violette, Jiang, Homin, Jinchi, Hao, Jung, Taehyun, Kallunki, Juha, Kirves, Petri, Kimura, Kimihiro, Koay, Jun Yi, Koch, Patrick M., Kramer, Carsten, Kraus, Alex, Kubo, Derek, Kuo, Cheng-Yu, Li, Chao-Te, Lin, Lupin Chun-Che, Liu, Ching-Tang, Liu, Kuan-Yu, Lo, Wen-Ping, Lu, Li-Ming, MacDonald, Nicholas, Martin-Cocher, Pierre, Messias, Hugo, Meyer-Zhao, Zheng, Minter, Anthony, Nair, Dhanya G., Nishioka, Hiroaki, Norton, Timothy J., Nystrom, George, Ogawa, Hideo, Oshiro, Peter, Patel, Nimesh A, Pen, Ue-Li, Pidopryhora, Yurii, Pradel, Nicolas, Raffin, Philippe A., Rao, Ramprasad, Ruiz, Ignacio, Sanchez, Salvador, Shaw, Paul, Snow, William, Sridharan, T. K., Srinivasan, Ranjani, Tercero, Belén, Torne, Pablo, Traianou, Efthalia, Wagner, Jan, Walther, Craig, Wei, Ta-Shun, Yang, Jun, and Yu, Chen-Yu

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies, General Relativity and Quantum Cosmology
Abstract

The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation^{1,2}. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole^3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of 8.4_{-1.1}^{+0.5} Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects in addition to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow., Comment: 50 pages, 18 figures, 3 tables, author's version of the paper published in Nature

Published
2023
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7. Comparison of Polarized Radiative Transfer Codes used by the EHT Collaboration

Author

Prather, Ben S., Dexter, Jason, Moscibrodzka, Monika, Pu, Hung-Yi, Bronzwaer, Thomas, Davelaar, Jordy, Younsi, Ziri, Gammie, Charles F., Gold, Roman, Wong, George N., Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Bach, Uwe, Baczko, Anne-Kathrin, Ball, David, Baloković, Mislav, Barrett, John, Bauböck, Michi, Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Bouman, Katherine L., Bower, Geoffrey C., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguiere, Dominique, Bustamante, Sandra, Byun, Do-Young, Carlstrom, John E., Ceccobello, Chiara, Chael, Andrew, Chan, Chi-kwan, Chang, Dominic O., Chatterjee, Koushik, Chatterjee, Shami, Chen, Ming-Tang, Chen, Yongjun, Cheng, Xiaopeng, Cho, Ilje, Christian, Pierre, Conroy, Nicholas S., Conway, John E., Cordes, James M., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Dhruv, Vedant, Doeleman, Sheperd S., Dougal, Sean, Dzib, Sergio A., Eatough, Ralph P., Emami, Razieh, Falcke, Heino, Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Ford, H. Alyson, Fraga-Encinas, Raquel, Freeman, William T., Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, García, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, Ciriaco, Gómez-Ruiz, Arturo I., Gómez, José L., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Haworth, Kari, Hecht, Michael H., Hesper, Ronald, Heumann, Dirk, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Impellizzeri, C. M. Violette, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Janssen, Michael, Jeter, Britton, Jiang, Wu, Jiménez-Rosales, Alejandra, Johnson, Michael D., Jorstad, Svetlana, Joshi, Abhishek V., Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kocherlakota, Prashant, Kofuji, Yutaro, Koyama, Shoko, Kramer, Carsten, Kramer, Michael, Krichbaum, Thomas P., Kuo, Cheng-Yu, La Bella, Noemi, Lauer, Tod R., Lee, Daeyoung, Lee, Sang-Sung, Leung, Po Kin, Levis, Aviad, Li, Zhiyuan, Lico, Rocco, Lindahl, Greg, Lindqvist, Michael, Lisakov, Mikhail, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lo, Wen-Ping, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin J., Lu, Ru-Sen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Martí-Vidal, Iván, Matsushita, Satoki, Matthews, Lynn D., Medeiros, Lia, Menten, Karl M., Michalik, Daniel, Mizuno, Izumi, Mizuno, Yosuke, Moran, James M., Moriyama, Kotaro, Müller, Cornelia, Mus, Alejandro, Musoke, Gibwa, Myserlis, Ioannis, Nadolski, Andrew, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayan, Ramesh, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Fuentes, Santiago Navarro, Neilsen, Joey, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Oh, Junghwan, Okino, Hiroki, Olivares, Héctor, Ortiz-León, Gisela N., Oyama, Tomoaki, Özel, Feryal, Palumbo, Daniel C. M., Paraschos, Georgios Filippos, Park, Jongho, Parsons, Harriet, Patel, Nimesh, Pen, Ue-Li, Pesce, Dominic W., Piétu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Pötzl, Felix M., Preciado-López, Jorge A., Psaltis, Dimitrios, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Rezzolla, Luciano, Ricarte, Angelo, Ripperda, Bart, Roelofs, Freek, Rogers, Alan, Ros, Eduardo, Romero-Cañizales, Cristina, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruiz, Ignacio, Ruszczyk, Chet, Rygl, Kazi L. J., Sánchez, Salvador, Sánchez-Argüelles, David, Sánchez-Portal, Miguel, Sasada, Mahito, Satapathy, Kaushik, Savolainen, Tuomas, Schloerb, F. Peter, Schonfeld, Jonathan, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Souccar, Kamal, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Torne, Pablo, Traianou, Efthalia, Trent, Tyler, Trippe, Sascha, Turk, Matthew, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Vos, Jesse, Wagner, Jan, Ward-Thompson, Derek, Wardle, John, Weintroub, Jonathan, Wex, Norbert, Wharton, Robert, Wielgus, Maciek, Wiik, Kaj, Witzel, Gunther, Wondrak, Michael F., Wu, Qingwen, Yamaguchi, Paul, Yfantis, Aristomenis, Yoon, Doosoo, Young, André, Young, Ken, Yu, Wei, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhang, Shuo, Zhao, Guang-Yao, and Zhao, Shan-Shan

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Interpretation of resolved polarized images of black holes by the Event Horizon Telescope (EHT) requires predictions of the polarized emission observable by an Earth-based instrument for a particular model of the black hole accretion system. Such predictions are generated by general relativistic radiative transfer (GRRT) codes, which integrate the equations of polarized radiative transfer in curved spacetime. A selection of ray-tracing GRRT codes used within the EHT collaboration is evaluated for accuracy and consistency in producing a selection of test images, demonstrating that the various methods and implementations of radiative transfer calculations are highly consistent. When imaging an analytic accretion model, we find that all codes produce images similar within a pixel-wise normalized mean squared error (NMSE) of 0.012 in the worst case. When imaging a snapshot from a cell-based magnetohydrodynamic simulation, we find all test images to be similar within NMSEs of 0.02, 0.04, 0.04, and 0.12 in Stokes I, Q, U , and V respectively. We additionally find the values of several image metrics relevant to published EHT results to be in agreement to much better precision than measurement uncertainties., Comment: Accepted for publication in ApJ

Published
2023
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8. 12CO (3-2) High-Resolution Survey (COHRS) of the Galactic Plane: Complete Data Release

Author

Park, Geumsook, Currie, Malcolm J., Thomas, Holly S., Rosolowsky, Erik, Dempsey, Jessica T., Kim, Kee-Tae, Rigby, Andrew J., Su, Yang, Eden, David J., Colombo, Dario, Parsons, Harriet, and Moore, Toby J. T.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We present the full data release of 12CO (3-2) High-Resolution Survey (COHRS), which has mapped the inner Galactic plane over the range of 9.5$^{\circ}$ $\le$ l $\le$ 62.3$^{\circ}$ and $|b| \le 0.5^{\circ}$. The COHRS has been carried out using the Heterodyne Array Receiver Program (HARP) on the 15 m James Clerk Maxwell Telescope (JCMT) in Hawaii. The released data are smoothed to have a spatial resolution of 16.6 arcsec and a velocity resolution of 0.635 km/s, achieving a mean root-mean-square of $\sim 0.6$ K on $T_\mathrm{A}^*$. The COHRS data are useful for investigating detailed three-dimensional structures of individual molecular clouds and large-scale structures such as spiral arms in the Galactic plane. Furthermore, data from other available public surveys of different CO isotopologues and transitions with similar angular resolutions to this survey, such as FUGIN, SEDIGISM, and CHIMPS/CHIMPS2, allow studying the physical properties of molecular clouds and comparing their states with each other. In this paper, we report further observations on R2 and improved data reduction since the original COHRS release. We discuss the characteristics of the COHRS data and present integrated-emission images and a position-velocity (PV) map of the region covered. The PV map shows a good match with the spiral-arm traces from the existing CO and HI surveys. We also obtain and compare integrated one-dimensional distributions of 12CO (1-0) and (3-2) and those of star-forming populations to each other., Comment: 29 pages, 13 figures, Accepted for publication in ApJS

Published
2022
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9. Submillimeter pulsations from the magnetar XTE J1810-197

Author

Torne, Pablo, Bell, Graham, Bintley, Dan, Desvignes, Gregory, Berry, David, Dempsey, Jessica T., Ho, Paul T. P., Parsons, Harriet, Eatough, Ralph P., Karuppusamy, Ramesh, Kramer, Michael, Kramer, Carsten, Liu, Kuo, Paubert, Gabriel, Sanchez-Portal, Miguel, and Schuster, Karl F.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We present the first detection of pulsations from a neutron star in the submillimeter range. The source is the magnetar XTE J1810-197, observed with the James Clerk Maxwell Telescope (JCMT) on 2020 February 27, 2020 July 9 and 2021 May 15. XTE J1810-197 is detected at 353 GHz ($\lambda=0.85\,$mm) in the three epochs, but not detected in the simultaneously-observed band at 666 GHz ($\lambda=0.45\,$mm). We measure an averaged flux density at 353 GHz of 6.7$\pm$1.0, 4.0$\pm$0.6, and 1.3$\pm$0.3 mJy and set 3$\sigma$ flux density upper limits at 666 GHz of 11.3, 4.7 and 4.3 mJy, at each of the three observing epochs, respectively. Combining close-in-time observations with the Effelsberg 100m and IRAM 30m telescopes covering non-contiguously from 6 to 225 GHz (5.0 cm$>\lambda>$1.33 mm), we investigate the spectral shape and frequency range of a potential spectral turn-up predicted by some pulsar radio emission models. The results demonstrate that the beamed radio emission from neutron stars can extend into the submillimeter regime, but are inconclusive on the existence and location of a potential spectral turn-up within the covered frequency range. The observed properties of the submillimeter emission resemble those of the longer wavelengths, and support a coherent mechanism for the production of pulsations at 353 GHz., Comment: 14 pages, 2 tables, 5 figures. Accepted for publication in ApJ Letters

Published
2022
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10. Event Horizon Telescope observations of the jet launching and collimation in Centaurus A

Author

Janssen, Michael, Falcke, Heino, Kadler, Matthias, Ros, Eduardo, Wielgus, Maciek, Akiyama, Kazunori, Baloković, Mislav, Blackburn, Lindy, Bouman, Katherine L., Chael, Andrew, Chan, Chi-kwan, Chatterjee, Koushik, Davelaar, Jordy, Edwards, Philip G., Fromm, Christian M., Gómez, José L., Goddi, Ciriaco, Issaoun, Sara, Johnson, Michael D., Kim, Junhan, Koay, Jun Yi, Krichbaum, Thomas P., Liu, Jun, Liuzzo, Elisabetta, Markoff, Sera, Markowitz, Alex, Marrone, Daniel P., Mizuno, Yosuke, Müller, Cornelia, Ni, Chunchong, Pesce, Dominic W., Ramakrishnan, Venkatessh, Roelofs, Freek, Rygl, Kazi L. J., van Bemmel, Ilse, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Baczko, Anne-Kathrin, Ball, David, Barrett, John, Benson, Bradford A., Bintley, Dan, Blundell, Raymond, Boland, Wilfred, Bower, Geoffrey C., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguiere, Dominique, Bronzwaer, Thomas, Byun, Do-Young, Carlstrom, John E., Chatterjee, Shami, Chen, Ming-Tang, Chen, Yongjun, Chesler, Paul M., Cho, Ilje, Christian, Pierre, Conway, John E., Cordes, James M., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Dexter, Jason, Doeleman, Sheperd S., Eatough, Ralph P., Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Ford, H. Alyson, Fraga-Encinas, Raquel, Friberg, Per, Fuentes, Antonio, Galison, Peter, Gammie, Charles F., García, Roberto, Gelles, Zachary, Gentaz, Olivier, Georgiev, Boris, Gold, Roman, Gómez-Ruiz, Arturo I., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Hecht, Michael H., Hesper, Ronald, Himwich, Elizabeth, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Inoue, Makoto, James, David J., Jannuzi, Buell T., Jeter, Britton, Jiang, Wu, Jimenez-Rosales, Alejandra, Jorstad, Svetlana, Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kino, Motoki, Kofuji, Yutaro, Koyama, Shoko, Kramer, Michael, Kramer, Carsten, Kuo, Cheng-Yu, Lauer, Tod R., Lee, Sang-Sung, Levis, Aviad, Li, Yan-Rong, Li, Zhiyuan, Lindqvist, Michael, Lico, Rocco, Lindahl, Greg, Liu, Kuo, Lo, Wen-Ping, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin, Lu, Ru-Sen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Marscher, Alan P., Martí-Vidal, Iván, Matsushita, Satoki, Matthews, Lynn D., Medeiros, Lia, Menten, Karl M., Mizuno, Izumi, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Musoke, Gibwa, Mejías, Alejandro Mus, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayan, Ramesh, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Neilsen, Joey, Neri, Roberto, Noutsos, Aristeidis, Nowak, Michael A., Okino, Hiroki, Olivares, Héctor, Ortiz-León, Gisela N., Oyama, Tomoaki, Özel, Feryal, Palumbo, Daniel C. M., Park, Jongho, Patel, Nimesh, Pen, Ue-Li, Piétu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Pötzl, Felix M., Prather, Ben, Preciado-López, Jorge A., Psaltis, Dimitrios, Pu, Hung-Yi, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Rezzolla, Luciano, Ricarte, Angelo, Ripperda, Bart, Rogers, Alan, Rose, Mel, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruszczyk, Chet, Sánchez, Salvador, Sánchez-Arguelles, David, Sasada, Mahito, Savolainen, Tuomas, Schloerb, F. Peter, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Torne, Pablo, Trent, Tyler, Traianou, Efthalia, Trippe, Sascha, van Langevelde, Huib Jan, van Rossum, Daniel R., Wagner, Jan, Ward-Thompson, Derek, Wardle, John, Weintroub, Jonathan, Wex, Norbert, Wharton, Robert, Wong, George N., Wu, Qingwen, Yoon, Doosoo, Young, André, Young, Ken, Younsi, Ziri, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhao, Guang-Yao, and Zhao, Shan-Shan

Subjects
Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

Very-long-baseline interferometry (VLBI) observations of active galactic nuclei at millimeter wavelengths have the power to reveal the launching and initial collimation region of extragalactic radio jets, down to $10-100$ gravitational radii ($r_g=GM/c^2$) scales in nearby sources. Centaurus A is the closest radio-loud source to Earth. It bridges the gap in mass and accretion rate between the supermassive black holes (SMBHs) in Messier 87 and our galactic center. A large southern declination of $-43^{\circ}$ has however prevented VLBI imaging of Centaurus A below ${\lambda}1$cm thus far. Here, we show the millimeter VLBI image of the source, which we obtained with the Event Horizon Telescope at $228$GHz. Compared to previous observations, we image Centaurus A's jet at a tenfold higher frequency and sixteen times sharper resolution and thereby probe sub-lightday structures. We reveal a highly-collimated, asymmetrically edge-brightened jet as well as the fainter counterjet. We find that Centaurus A's source structure resembles the jet in Messier 87 on ${\sim}500r_g$ scales remarkably well. Furthermore, we identify the location of Centaurus A's SMBH with respect to its resolved jet core at ${\lambda}1.3$mm and conclude that the source's event horizon shadow should be visible at THz frequencies. This location further supports the universal scale invariance of black holes over a wide range of masses., Comment: 27 pages, 9 figures. This is a post-peer-review, pre-copyedit version of an article published in Nature Astronomy. The final authenticated version is available online at: https://doi.org/10.1038/s41550-021-01417-w

Published
2021
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11. The Variability of the Black-Hole Image in M87 at the Dynamical Time Scale

Author

Satapathy, Kaushik, Psaltis, Dimitrios, Ozel, Feryal, Medeiros, Lia, Dougall, Sean T., Chan, Chi-kwan, Wielgus, Maciek, Prather, Ben S., Wong, George N., Gammie, Charles F., Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Baczko, Anne-Kathrin, Ball, David R., Baloković, Mislav, Barrett, John, Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Boland, Wilfred, Bouman, Katherine L., Bower, Geoffrey C., Boyce, Hope A., Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguiere, Dominique, Bronzwaer, Thomas, Bustamente, Sandra, Byun, Do-Young, Carlstrom, John E., Chael, Andrew, Chatterjee, Koushik, Chatterjee, Shami, Chen, Ming-Tang, Chen, Yongjun, Cho, Ilje, Christian, Pierre, Conway, John E., Cordes, James M., Crawford, Thomas, Crew, Geoffrey B., Osorio, Alejandro Cruz, Cui, Yuzhu, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica T., Desvignes, Gregory, Dexter, Jason, Doeleman, Sheperd S., Eatough, Ralph, Falcke, Heino, Farah, Joseph R., Fish, Vincent, Fomalont, Edward B., Ford, H. Alyson, Fraga-Encinas, Raquel, Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, García, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, Ciriaco, Gold, Roman, Gomez-Ruiz, Arturo I., Gómez, Jose L., Gu, Minfeng, Gurwell, Mark A., Hada, Kazuhiro, Haggard, Daryl, Hecht, Michael, Hesper, Ronald, Ho, Luis C., Ho, Paul T., Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Janssen, Michael, Jeter, Britton, Jiang, Wu, Rosales, Alejandra Jimenez, Johnson, Michael D., Jorstad, Svetlana G., Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kofuji, Yutaro, Koch, Patrick M., Koyama, Shoko, Kramer, Carsten, Kramer, Michael, Krichbaum, Thomas P., Kuo, Cheng-Yu, Lauer, Tod R., Lee, Sang-Sung, Levis, Aviad, Li, Yan-Rong, Li, Zhiyuan, Lindqvist, Michael, Lico, Rocco, Lindahl, Greg, Liu, Jun, Liu, Kuo, Liuzzo, Miss Elisabetta, Lo, Wen-Ping, Lobanov, Andrei, Loinard, Laurent, Lonsdale, Colin J., Lu, Rusen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel, Marscher, Alan P., Marti-Vidal, Ivan, Matsushita, Satoki, Matthews, Lynn, Menten, Karl M., Mizuno, Izumi, Mizuno, Yosuke, Moran, James, Moriyama, Kotaro, Moscibrodzka, Monika, Muller, Cornelia, Mejias, Alejandro M., Musoke, Gibwa, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayan, Ramesh, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Neilsen, Joey, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Okino, Hiroki, Olivares, Hector, Ortiz-Leon, Gisela N., Oyama, Tomoaki, Palumbo, Daniel C., Park, Jongho, Patel, Nimesh A., Pen, Ue-Li, Pesce, Dominic W., Pietu, Vincent, Plambeck, Richard L., PopStefanija, Aleksandar, Porth, Oliver, Potzl, Felix, Preciado-López, Jorge A., Pu, Hung-Yi, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark, Raymond, Alexander W., Rezzolla, Luciano, Ripperda, Bart, Roelofs, Freek, Rogers, Alan E. E., Ros, Eduardo, Rose, Mel, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruszczyk, Chet, Rygl, Kazi, Sanchez, Salvador, Sanchez-Arguelles, David, Sasada, Mahito, Savolainen, Tuomas, Schloerb, F Peter, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhi-Qiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo, Titus, Michael, Toma, Kenji, Torne, Pablo, Traianou, E., Trent, Tyler, Trippe, Sascha, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Wagner, Jan, Ward-Thompson, Derek, Wardle, John F., Weintroub, Jonathan, Wex, Norbert, Wharton, Robert, Wiik, Kaj, Wu, Qingwen, Yoon, DooSoo, Young, Andre, Young, Ken H., Younsi, Ziri, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhao, Guang-Yao, and Zhao, Shan-Shan

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The black-hole images obtained with the Event Horizon Telescope (EHT) are expected to be variable at the dynamical timescale near their horizons. For the black hole at the center of the M87 galaxy, this timescale (5-61 days) is comparable to the 6-day extent of the 2017 EHT observations. Closure phases along baseline triangles are robust interferometric observables that are sensitive to the expected structural changes of the images but are free of station-based atmospheric and instrumental errors. We explored the day-to-day variability in closure phase measurements on all six linearly independent non-trivial baseline triangles that can be formed from the 2017 observations. We showed that three triangles exhibit very low day-to-day variability, with a dispersion of $\sim3-5^\circ$. The only triangles that exhibit substantially higher variability ($\sim90-180^\circ$) are the ones with baselines that cross visibility amplitude minima on the $u-v$ plane, as expected from theoretical modeling. We used two sets of General Relativistic magnetohydrodynamic simulations to explore the dependence of the predicted variability on various black-hole and accretion-flow parameters. We found that changing the magnetic field configuration, electron temperature model, or black-hole spin has a marginal effect on the model consistency with the observed level of variability. On the other hand, the most discriminating image characteristic of models is the fractional width of the bright ring of emission. Models that best reproduce the observed small level of variability are characterized by thin ring-like images with structures dominated by gravitational lensing effects and thus least affected by turbulence in the accreting plasmas., Comment: Accepted for Publication in ApJ

Published
2021
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12. A Decade of SCUBA-2: A Comprehensive Guide to Calibrating 450 $\mu$m and 850 $\mu$m Continuum Data at the JCMT

Author

Mairs, Steve, Dempsey, Jessica T., Bell, Graham S., Parsons, Harriet, Currie, Malcolm J., Friberg, Per, Jiang, Xue-Jian, Tetarenko, Alexandra J., Bintley, Dan, Cookson, Jamie, Li, Shaoliang, Rawlings, Mark G., Wouterloot, Jan, Berry, David, Graves, Sarah, Mizuno, Izumi, Acohido, Alexis Ann, Clark, Alyssa, Cox, Jeff, Fuchs, Miriam, Hoge, James, Kemp, Johnathon, Lee, E'lisa, Matulonis, Callie, Montgomerie, William, Silva, Kevin, and Smith, Patrice

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The Submillimetre Common User Bolometer Array 2 (SCUBA-2) is the James Clerk Maxwell Telescope's continuum imager, operating simultaneously at 450 and 850~$\mu$m. SCUBA-2 was commissioned in 2009--2011 and since that time, regular observations of point-like standard sources have been performed whenever the instrument is in use. Expanding the calibrator observation sample by an order of magnitude compared to previous work, in this paper we derive updated opacity relations at each wavelength for a new atmospheric-extinction correction, analyze the Flux-Conversion Factors (FCFs) used to convert instrumental units to physical flux units as a function of date and observation time, present information on the beam profiles for each wavelength, and update secondary-calibrator source fluxes. Between 07:00 and 17:00 UTC, the portion of the night that is most stable to temperature gradients that cause dish deformation, the total-flux uncertainty and the peak-flux uncertainty measured at 450~$\mu$m are found to be 14\% and 17\%, respectively. Measured at 850~$\mu$m, the total-flux and peak-flux uncertainties are 6\%, and 7\%, respectively. The analysis presented in this work is applicable to all SCUBA-2 projects observed since 2011., Comment: 31 pages, 15 figures, 8 tables. This is the Accepted Manuscript version of an article accepted for publication in the Astronomical Journal. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. This Accepted Manuscript is published under a CC BY licence

Published
2021
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13. Constraints on black-hole charges with the 2017 EHT observations of M87*

Author

Kocherlakota, Prashant, Rezzolla, Luciano, Falcke, Heino, Fromm, Christian M., Kramer, Michael, Mizuno, Yosuke, Nathanail, Antonios, Olivares, Hector, Younsi, Ziri, Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Baczko, Anne-Kathrin, Ball, David, Balokovic, Mislav, Barrett, John, Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Boland, Wilfred, Bouman, Katherine L., Bower, Geoffrey C., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguiere, Dominique, Bronzwaer, Thomas, Byun, Do-Young, Carlstrom, John E., Chael, Andrew, Chan, Chi-kwan, Chatterjee, Shami, Chatterjee, Koushik, Chen, Ming-Tang, Chen, Yongjun, Chesler, Paul M., Cho, Ilje, Christian, Pierre, Conway, John E., Cordes, James M., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Doeleman, Sheperd S., Eatough, Ralph P., Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Fraga-Encinas, Raquel, Friberg, Per, Ford, H. Alyson, Fuentes, Antonio, Galison, Peter, Gammie, Charles F., Garcia, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, Ciriaco, Gold, Roman, Gomez, Jose L., Gomez-Ruiz, Arturo I., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Hecht, Michael H., Hesper, Ronald, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Janssen, Michael, Jeter, Britton, Jiang, Wu, Jimenez-Rosales, Alejandra, Johnson, Michael D., Jorstad, Svetlana, Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kofuji, Yutaro, Koch, Patrick M., Koyama, Shoko, Kramer, Carsten, Krichbaum, Thomas P., Kuo, Cheng-Yu, Lauer, Tod R., Lee, Sang-Sung, Levis, Aviad, Li, Yan-Rong, Li, Zhiyuan, Lindqvist, Michael, Lico, Rocco, Lindahl, Greg, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lo, Wen-Ping, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin, Lu, Ru-Sen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Marti-Vidal, Ivan, Matsushita, Satoki, Matthews, Lynn D., Medeiros, Lia, Menten, Karl M., Mizuno, Izumi, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Muller, Cornelia, Musoke, Gibwa, Mejias, Alejandro Mus, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayan, Ramesh, Narayanan, Gopal, Natarajan, Iniyan, Neilsen, Joseph, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Okino, Hiroki, Ortiz-Leon, Gisela N., Oyama, Tomoaki, Ozel, Feryal, Palumbo, Daniel C. M., Park, Jongho, Patel, Nimesh, Pen, Ue-Li, Pesce, Dominic W., Pietu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Potzl, Felix M., Prather, Ben, Preciado-Lopez, Jorge A., Psaltis, Dimitrios, Pu, Hung-Yi, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Ricarte, Angelo, Ripperda, Bart, Roelofs, Freek, Rogers, Alan, Ros, Eduardo, Rose, Mel, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruszczyk, Chet, Rygl, Kazi L. J., Sanchez, Salvador, Sanchez-Arguelles, David, Sasada, Mahito, Savolainen, Tuomas, Schloerb, F. Peter, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Toma, Kenji, Torne, Pablo, Trent, Tyler, Traianou, Efthalia, Trippe, Sascha, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Wagner, Jan, Ward-Thompson, Derek, Wardle, John, Weintroub, Jonathan, Wex, Norbert, Wharton, Robert, Wielgus, Maciek, Wong, George N., Wu, Qingwen, Yoon, Doosoo, Young, Andre, Young, Ken, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhao, Guang-Yao, Zhao, Shan-Shan, and Collaboration, The EHT

Subjects
General Relativity and Quantum Cosmology
Abstract

Our understanding of strong gravity near supermassive compact objects has recently improved thanks to the measurements made by the Event Horizon Telescope (EHT). We use here the M87* shadow size to infer constraints on the physical charges of a large variety of nonrotating or rotating black holes. For example, we show that the quality of the measurements is already sufficient to rule out that M87* is a highly charged dilaton black hole. Similarly, when considering black holes with two physical and independent charges, we are able to exclude considerable regions of the space of parameters for the doubly-charged dilaton and the Sen black holes., Comment: 15 pages, 4 figures, published in PRD on May 19

Published
2021
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14. The Polarized Image of a Synchrotron Emitting Ring of Gas Orbiting a Black Hole

Author

Narayan, Ramesh, Palumbo, Daniel C. M., Johnson, Michael D., Gelles, Zachary, Himwich, Elizabeth, Chang, Dominic O., Ricarte, Angelo, Dexter, Jason, Gammie, Charles F., Chael, Andrew A., Collaboration, The Event Horizon Telescope, Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Baczko, Anne-Kathrin, Ball, David, Balokovic, Mislav, Barrett, John, Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Boland, Wilfred, Bouman, Katherine L., Bower, Geoffrey C., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguiere, Dominique, Bronzwaer, Thomas, Byun, Do-Young, Carlstrom, John E., Chan, Chi-kwan, Chatterjee, Shami, Chatterjee, Koushik, Chen, Ming-Tang, Chen, Yongjun, Chesler, Paul M., Cho, Ilje, Christian, Pierre, Conway, John E., Cordes, James M., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, Davelaar, Jordy, DeLaurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Doeleman, Sheperd S., Eatough, Ralph P., Falcke, Heino, Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Ford, H. Alyson, Fraga-Encinas, Raquel, Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, Garcıa, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, Ciriaco, Gold, Roman, Gomez, Jose L., Gomez-Ruiz, Arturo I., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Hecht, Michael H., Hesper, Ronald, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Janssen, Michael, Jeter, Britton, Jiang, Wu, Jimenez-Rosales, Alejandra, Jorstad, Svetlana, Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kofuji, Yutaro, Koch, Patrick M., Koyama, Shoko, Kramer, Michael, Kramer, Carsten, Krichbaum, Thomas P., Kuo, Cheng-Yu, Lauer, Tod R., Lee, Sang-Sung, Levis, Aviad, Li, Yan-Rong, Li, Zhiyuan, Lindqvist, Michael, Lico, Rocco, Lindahl, Greg, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lo, Wen-Pin, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin, Lu, Ru-Sen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Martı-Vidal, Alan P. Marscher Ivan, Matsushita, Satoki, Matthews, Lynn D., Medeiros, Lia, Menten, Karl M., Mizuno, Izumi, Mizuno, Yosuke, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Muller, Cornelia, Musoke, Gibwa, Mejıas, Alejandro Mus, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Neilsen, Joey, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Okino, Hiroki, Olivares, Hector, Ortiz-Leon, Gisela N., Oyama, Tomoaki, Ozel, Feryal, Park, Jongho, Patel, Nimesh, Pen, Ue-Li, Pesce, Dominic W., Pietu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Potzl, Felix M., Prather, Ben, Preciado-Lopez, Jorge A., Psaltis, Dimitrios, Pu, Hung-Yi, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Rezzolla, Luciano, Ripperda, Bart, Roelofs, Freek, Rogers, Alan, Ros, Eduardo, Rose, Mel, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruszczyk, Chet, Rygl, Kazi L. J., Sanchez, Salvador, Sanchez-Arguelles, David, Sasada, Mahito, Savolainen, Tuomas, Schloerb, F. Peter, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Toma, Kenji, Torne, Pablo, Trent, Tyler, Traianou, Efthalia, Trippe, Sascha, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Wagner, Jan, Ward-Thompson, Derek, Wardle, John, Weintroub, Jonathan, Wex, Norbert, Wharton, Robert, Wielgus, Maciek, Wong, George N., Wu, Qingwen, Yoon, Doosoo, Young, Andre, Young, Ken, Younsi, Ziri, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhao, Guang-Yao, and Zhao, Shan-Shan

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Synchrotron radiation from hot gas near a black hole results in a polarized image. The image polarization is determined by effects including the orientation of the magnetic field in the emitting region, relativistic motion of the gas, strong gravitational lensing by the black hole, and parallel transport in the curved spacetime. We explore these effects using a simple model of an axisymmetric, equatorial accretion disk around a Schwarzschild black hole. By using an approximate expression for the null geodesics derived by Beloborodov (2002) and conservation of the Walker-Penrose constant, we provide analytic estimates for the image polarization. We test this model using currently favored general relativistic magnetohydrodynamic simulations of M87*, using ring parameters given by the simulations. For a subset of these with modest Faraday effects, we show that the ring model broadly reproduces the polarimetric image morphology. Our model also predicts the polarization evolution for compact flaring regions, such as those observed from Sgr A* with GRAVITY. With suitably chosen parameters, our simple model can reproduce the EVPA pattern and relative polarized intensity in Event Horizon Telescope images of M87*. Under the physically motivated assumption that the magnetic field trails the fluid velocity, this comparison is consistent with the clockwise rotation inferred from total intensity images., Comment: 29 pages, 11 figures, published in ApJ on May 3

Published
2021
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15. Implementing Remote Observing at the JCMT

Author

Parsons, Harriet, Dempsey, Jessica, Bintley, Dan, Walther, Craig, Graves, Sarah, Stahm, William, Purves, Maren, Silva, Kevin, Acohido, Alexis, Bell, Graham, Berthold, Ryan, Cookson, Jamie, DeMattos, Vernon, Estrada, Devin, Fuchs, Miriam, Fuselier, David, Ho, Paul, Kuroda, John, Li, Shaoliang, Mairs, Steven, and Rawlings, Mark

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The James Clerk Maxwell Telescope (JCMT) is the largest single dish telescope in the world focused on sub-millimeter astronomy - and it remains at the forefront of sub-millimeter discovery space. JCMT continues itspush for higher efficiency and greater science impact with a switch to fully remote operation. This switch toremote operations occurred on November 1st 2019. The switch to remote operations should be recognized to bepart of a decade long process involving incremental changes leading to Extended Observing - observing beyondthe classical night shift - and eventually to full remote operations. The success of Remote Observing is indicatedin the number of productive hours and continued low fault rate from before and after the switch., Comment: 16 pages, 4 figures, SPIE Astronomical Telescopes + Instrumentation 2020, Paper Number: 11449-17

Published
2020

16. Commissioning of Namakanui on the JCMT

Author

Mizuno, Izumi, Friberg, Per, Berthold, Ryan, Parsons, Harriet, Han, Chih-Chiang, Acohido, Alexis, Bell, Graham, Berry, David, Bintley, Dan, Chen, Ming-Tang, Clark, Alyssa, Cookson, Jamie, Demattos, Vernon, Dempsey, Jessica, Fleck, Jason, Fu, Kuo-chieh, Fuchs, Miriam, Graves, Sarah, Ho, Paul, Hsu, Sung-Po, Huang, YauDe, Jiang, Xue-Jian, Kubo, Derek, JohnKuroda, Li, Shaoliang, Mairs, Steve, Matulonis, Callie, Neal, Mailani, Oliveira, Neal, Purves, Maren, Rawlings, Mark, Shih, Ya-Che, Silva, Kevin, Sison, Ed, Smith, Patrice, Srinivasan, Ranjani, Stahm, William, Tetarenko, Alexandra J., Torne, Pablo, Walther, Craig, Wang, Chao-Ching, and Wei, Ta-Shun

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Namakanui is an instrument containing three inserts in an ALMA type Dewar. The three inserts are Alaihi, Uu and Aweoweo operating around 86, 230 and 345GHz. The receiver is being commissioned on the JCMT. It will be used for both Single dish and VLBI observations. We will present commissioning results and the system., Comment: 19 pages, 16 figures, Proceedings of SPIE

Published
2020

17. Automated Project Completion Forecasting

Author

Tetarenko, Alexandra J., Parsons, Harriet, Graves, Sarah, and Dempsey, Jessica

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

In the age of Large Programs and Big Data a key component in project planning for ground-based astronomical observatories is understanding how to balance users demands and telescope capabilities. In particular, future planning for operations requires us to asses the impact of a complex set of parameters, such as right ascension, instrument, and sky condition pressures over coming semesters. Increased understanding of these parameters can provide: improved scientific output, better management of user expectations, more accurate advertised/allocated time under a Call for Proposals, and improved scheduling for instrumental commissioning and engineering work. We present ongoing efforts by staff at the James Clerk Maxwell Telescope (JCMT) to build a tool to provide automated completion forecasting of Large Programs undertaken at this telescope, which make up 50% of the observing time available at the JCMT., Comment: 12 pages, 9 figures, SPIE Astronomical Telescopes + Instrumentation 2020, Paper Number: 11449-51

Published
2020
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18. Gravitational Test Beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole

Author

Psaltis, Dimitrios, Medeiros, Lia, Christian, Pierre, Ozel, Feryal, Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Asada, Keiichi, Azulay, Rebecca, Ball, David, Balokovic, Mislav, Barrett, John, Bintley, Dan, Blackburn, Lindy, Boland, Wilfred, Bower, Geoffrey C., Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broguiere, Dominique, Bronzwaer, Thomas, Byun, Do-Young, Carlstrom, John E., Chael, Andrew, Chan, Chi-kwan, Chatterjee, Shami, Chatterjee, Koushik, Chen, Ming-Tang, Chen, Yongjun, Cho, Ilje, Conway, John E., Cordes, James M., Crew, Geoffrey B., Cui, Yuzhu, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Dexter, Jason, Eatough, Ralph P., Falcke, Heino, Fish, Vincent L., Fomalont, Ed, Fraga-Encinas, Raquel, Friberg, Per, Fromm, Christian M., Gammie, Charles F., García, Roberto, Gentaz, Olivier, Goddi, Ciriaco, Gomez, Jose L., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Hesper, Ronald, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Janssen, Michael, Jiang, Wu, Jimenez-Rosales, Alejandra, Johnson, Michael D., Jorstad, Svetlana, Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Jae-Young, Kim, Junhan, Kim, Jongsoo, Kino, Motoki, Koay, Jun Yi, Koch, Patrick M., Koyama, Shoko, Kramer, Michael, Kramer, Carsten, Krichbaum, Thomas P., Kuo, Cheng-Yu, Lauer, Tod R., Lee, Sang-Sung, Li, Yan-Rong, Li, Zhiyuan, Lindqvist, Michael, Lico, Rocco, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lo, Wen-Ping, Lobanov, Andrei P., Lonsdale, Colin, Lu, Ru-Sen, Mao, Jirong, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Martí-Vidal, Ivan, Matsushita, Satoki, Mizuno, Yosuke, Mizuno, Izumi, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Muller, Cornelia, Musoke, Gibwa, Mejías, Alejandro Mus, Nagai, Hiroshi, Nagar, Neil M., Narayan, Ramesh, Narayanan, Gopal, Natarajan, Iniyan, Neri, Roberto, Noutsos, Aristeidis, Okino, Hiroki, Olivares, Hector, Oyama, Tomoaki, Palumbo, Daniel C. M., Park, Jongho, Patel, Nimesh, Pen, Ue-Li, Pietu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Prather, Ben, Preciado-Lopez, Jorge A., Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Ripperda, Bart, Roelofs, Freek, Rogers, Alan, Ros, Eduardo, Rose, Mel, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruszczyk, Chet, Ryan, Benjamin R., Rygl, Kazi L. J., Sanchez, Salvador, Sanchez-Arguelles, David, Sasada, Mahito, Savolainen, Tuomas, Schloerb, F. Peter, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Tazaki, Fumie, Tilanus, Remo P. J., Titus, Michael, Torne, Pablo, Trent, Tyler, Traianou, Efthalia, Trippe, Sascha, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Wagner, Jan, Wardle, John, Ward-Thompson, Derek, Weintroub, Jonathan, Wex, Norbert, Wharton, Robert, Wielgus, Maciek, Wong, George N., Wu, Qingwen, Yoon, Doosoo, Young, Andre, Young, Ken, Younsi, Ziri, Yuan, Feng, Yuan, Ye-Fei, Zhao, Shan-Shan, and Collaboration, the EHT

Subjects
General Relativity and Quantum Cosmology, Astrophysics - High Energy Astrophysical Phenomena
Abstract

The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources., Comment: Physical Review Letters

Published
2020
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20. The integrated properties of the molecular clouds from the JCMT CO(3-2) High Resolution Survey

Author

Colombo, Dario, Rosolowsky, Erik, Duarte-Cabral, Ana, Ginsburg, Adam, Glenn, Jason, Zetterlund, Erika, Hernandez, Audra K., Dempsey, Jessica, and Currie, Malcolm J.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We define the molecular cloud properties of the Milky Way first quadrant using data from the JCMT CO(3-2) High Resolution Survey. We apply the Spectral Clustering for Interstellar Molecular Emission Segmentation (SCIMES) algorithm to extract objects from the full-resolution dataset, creating the first catalog of molecular clouds with a large dynamic range in spatial scale. We identify $>85\,000$ clouds with two clear sub-samples: $\sim35\,500$ well-resolved objects and $\sim540$ clouds with well-defined distance estimations. Only 35% of the cataloged clouds (as well as the total flux encompassed by them) appear enclosed within the Milky Way spiral arms. The scaling relationships between clouds with known distances are comparable to the characteristics of the clouds identified in previous surveys. However, these relations between integrated properties, especially from the full catalog, show a large intrinsic scatter ($\sim0.5$ dex), comparable to other cloud catalogs of the Milky Way and nearby galaxies. The mass distribution of molecular clouds follows a truncated-power law relationship over three orders of magnitude in mass with a form $dN/dM \propto M^{-1.7}$ with a clearly defined truncation at an upper mass of $M_0 \sim 3 \times 10^6~M_\odot$, consistent with theoretical models of cloud formation controlled by stellar feedback and shear. Similarly, the cloud population shows a power-law distribution of size with $dN/dR \propto R^{-2.8}$ with a truncation at $R_0 = 70$ pc., Comment: 58 pages, 46 figure. Accepted for publication in MNRAS. A new, fully documented, version of SCIMES is public available on Github (https://github.com/Astroua/SCIMES). The molecular cloud integrated property catalog is public available on Zenodo (https://doi.org/10.5281/zenodo.2207059)

Published
2018
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21. Electronics Instrumentation for the Greenland Telescope

Author

Kubo, Derek, Han, Chih-Chiang, Nishioka, Hiroaki, Chilson, Ryan, Srinivasan, Ranjani, Yen, Sheng- Feng, Fu, Kuo-Chieh, Jiang, Homin, Liu, Kuan-Yu, Wei, Ta-Shun, Huang, Chih-Wei, Yu, Chen- Yu, Oshiro, Peter, Chang, Shu-Hao, Chen, Chung-Cheng, Raffin, Philippe, Huang, Yau-De, Martin-Cocher, Pierre, Chen, Ming-Tang, Inoue, Makoto, Matsushita, Satoki, Asada, Keiichi, Koyama, Shoko, Koch, Patrick, Ho, Paul T. P., Shaw, Yang-Tai, Norton, Timothy J., Patel, Nimesh A., Doeleman, Shepherd S., Bintley, Daniel, Walther, Craig, Friberg, Per, Dempsey, Jessica, Ogawa, Hideo, Kimura, Kimihiro, Hasegawa, Yutaka, Liu, Ching-Tang, Han, Kou-Chang, Chang, Song-Chu, and Lu, Li-Ming

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The Greenland Telescope project has recently participated in an experiment to image the supermassive black hole shadow at the center of M87 using Very Long Baseline Interferometry technique in April of 2018. The antenna consists of the 12-m ALMA North American prototype antenna that was modified to support two auxiliary side containers and to withstand an extremely cold environment. The telescope is currently at Thule Air Base in Greenland with the long-term goal to move the telescope over the Greenland ice sheet to Summit Station. The GLT currently has a single cryostat which houses three dual polarization receivers that cover 84-96 GHz, 213-243 GHz and 271-377 GHz bands. A hydrogen maser frequency source in conjunction with high frequency synthesizers are used to generate the local oscillator references for the receivers. The intermediate frequency outputs of each receiver cover 4-8 GHz and are heterodyned to baseband for digitization within a set of ROACH-2 units then formatted for recording onto Mark-6 data recorders. A separate set of ROACH-2 units operating in parallel provides the function of auto-correlation for real-time spectral analysis. Due to the stringent instrumental stability requirements for interferometry a diagnostic test system was incorporated into the design. Tying all of the above equipment together is the fiber optic system designed to operate in a low temperature environment and scalable to accommodate a larger distance between the control module and telescope for Summit Station. A report on the progress of the above electronics instrumentation system will be provided., Comment: 19 pages, 37 figures, oral presentation at the June 2018 SPIE conference: Astronomical Telescopes + Instrumentation, in the section on Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX

Published
2018

24. How does the environmental state “see” endangered marine animals?

Author

Doebeli, Anna Gabriela, Magnuson, Briana, Yoon-Henderson, Kihan, Collard, Rosemary, Dempsey, Jessica, Walter, Michele (River), Carre, Marianne, Corrado, Maggy, Dhaliwal, Rajdeep, Giesting, Anna, Gonchar, Karina, Hsu, Chris, Johnson, Tamara, Karve, Urvee, Lam, Enoch, Nelson, Karyn, Teske, Morgan, Valente, Emily, Wang, Isabella, Wheaton, Paige, Hetherington, Chloe, Hsu, Louisa, Wen, Can, and Yeung, Christa

Published
2021
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25. A Search for Pulsars around Sgr A* in the First Event Horizon Telescope Data Set

Author

Torne, Pablo, primary, Liu, Kuo, additional, Eatough, Ralph P., additional, Wongphechauxsorn, Jompoj, additional, Cordes, James M., additional, Desvignes, Gregory, additional, De Laurentis, Mariafelicia, additional, Kramer, Michael, additional, Ransom, Scott M., additional, Chatterjee, Shami, additional, Wharton, Robert, additional, Karuppusamy, Ramesh, additional, Blackburn, Lindy, additional, Janssen, Michael, additional, Chan, Chi-kwan, additional, Crew, Geoffrey, B., additional, Matthews, Lynn D., additional, Goddi, Ciriaco, additional, Rottmann, Helge, additional, Wagner, Jan, additional, Sánchez, Salvador, additional, Ruiz, Ignacio, additional, Abbate, Federico, additional, Bower, Geoffrey C., additional, Salamanca, Juan J., additional, Gómez-Ruiz, Arturo I., additional, Herrera-Aguilar, Alfredo, additional, Jiang 江, Wu 悟, additional, Lu 路, Ru-Sen 如森, additional, Pen, Ue-Li, additional, Raymond, Alexander W., additional, Shao, Lijing, additional, Shen 沈, Zhiqiang 志强, additional, Paubert, Gabriel, additional, Sanchez-Portal, Miguel, additional, Kramer, Carsten, additional, Castillo, Manuel, additional, Navarro, Santiago, additional, John, David, additional, Schuster, Karl-Friedrich, additional, Johnson, Michael D., additional, Rygl, Kazi L. J., additional, Akiyama, Kazunori, additional, Alberdi, Antxon, additional, Alef, Walter, additional, Algaba, Juan Carlos, additional, Anantua, Richard, additional, Asada, Keiichi, additional, Azulay, Rebecca, additional, Bach, Uwe, additional, Baczko, Anne-Kathrin, additional, Ball, David, additional, Baloković, Mislav, additional, Barrett, John, additional, Bauböck, Michi, additional, Benson, Bradford A., additional, Bintley, Dan, additional, Blundell, Raymond, additional, Bouman, Katherine L., additional, Boyce, Hope, additional, Bremer, Michael, additional, Brinkerink, Christiaan D., additional, Brissenden, Roger, additional, Britzen, Silke, additional, Broderick, Avery E., additional, Broguiere, Dominique, additional, Bronzwaer, Thomas, additional, Bustamante, Sandra, additional, Byun, Do-Young, additional, Carlstrom, John E., additional, Ceccobello, Chiara, additional, Chael, Andrew, additional, Chang, Dominic O., additional, Chatterjee, Koushik, additional, Chen, Ming-Tang, additional, Chen 陈, Yongjun 永军, additional, Cheng, Xiaopeng, additional, Cho, Ilje, additional, Christian, Pierre, additional, Conroy, Nicholas S., additional, Conway, John E., additional, Crawford, Thomas M., additional, Cruz-Osorio, Alejandro, additional, Cui 崔, Yuzhu 玉竹, additional, Dahale, Rohan, additional, Davelaar, Jordy, additional, Deane, Roger, additional, Dempsey, Jessica, additional, Dexter, Jason, additional, Dhruv, Vedant, additional, Doeleman, Sheperd S., additional, Dougal, Sean, additional, Dzib, Sergio A., additional, Emami, Razieh, additional, Falcke, Heino, additional, Farah, Joseph, additional, Fish, Vincent L., additional, Fomalont, Ed, additional, Ford, H. Alyson, additional, Foschi, Marianna, additional, Fraga-Encinas, Raquel, additional, Freeman, William T., additional, Friberg, Per, additional, Fromm, Christian M., additional, Fuentes, Antonio, additional, Galison, Peter, additional, Gammie, Charles F., additional, García, Roberto, additional, Gentaz, Olivier, additional, Georgiev, Boris, additional, Gold, Roman, additional, Gómez, José L., additional, Gu 顾, Minfeng 敏峰, additional, Gurwell, Mark, additional, Hada, Kazuhiro, additional, Haggard, Daryl, additional, Haworth, Kari, additional, Hecht, Michael H., additional, Hesper, Ronald, additional, Heumann, Dirk, additional, Ho 何, Luis C. 子山, additional, Ho, Paul, additional, Honma, Mareki, additional, Huang, Chih-Wei L., additional, Huang 黄, Lei 磊, additional, Hughes, David H., additional, Ikeda, Shiro, additional, Impellizzeri, C. M. Violette, additional, Inoue, Makoto, additional, Issaoun, Sara, additional, James, David J., additional, Jannuzi, Buell T., additional, Jeter, Britton, additional, Jiménez-Rosales, Alejandra, additional, Jorstad, Svetlana, additional, Joshi, Abhishek V., additional, Jung, Taehyun, additional, Karami, Mansour, additional, Kawashima, Tomohisa, additional, Keating, Garrett K., additional, Kettenis, Mark, additional, Kim, Dong-Jin, additional, Kim, Jae-Young, additional, Kim, Jongsoo, additional, Kim, Junhan, additional, Kino, Motoki, additional, Koay, Jun Yi, additional, Kocherlakota, Prashant, additional, Kofuji, Yutaro, additional, Koyama, Shoko, additional, Krichbaum, Thomas P., additional, Kuo, Cheng-Yu, additional, La Bella, Noemi, additional, Lauer, Tod R., additional, Lee, Daeyoung, additional, Lee, Sang-Sung, additional, Leung, Po Kin, additional, Levis, Aviad, additional, Li 李, Zhiyuan 志远, additional, Lico, Rocco, additional, Lindahl, Greg, additional, Lindqvist, Michael, additional, Lisakov, Mikhail, additional, Liu 刘, Jun 俊, additional, Liuzzo, Elisabetta, additional, Lo, Wen-Ping, additional, Lobanov, Andrei P., additional, Loinard, Laurent, additional, Lonsdale, Colin J., additional, MacDonald, Nicholas R., additional, Mao 毛, Jirong 基荣, additional, Marchili, Nicola, additional, Markoff, Sera, additional, Marrone, Daniel P., additional, Marscher, Alan P., additional, Martí-Vidal, Iván, additional, Matsushita, Satoki, additional, Medeiros, Lia, additional, Menten, Karl M., additional, Michalik, Daniel, additional, Mizuno, Izumi, additional, Mizuno, Yosuke, additional, Moran, James M., additional, Moriyama, Kotaro, additional, Moscibrodzka, Monika, additional, Müller, Cornelia, additional, Müller, Hendrik, additional, Mus, Alejandro, additional, Musoke, Gibwa, additional, Myserlis, Ioannis, additional, Nadolski, Andrew, additional, Nagai, Hiroshi, additional, Nagar, Neil M., additional, Nakamura, Masanori, additional, Narayan, Ramesh, additional, Narayanan, Gopal, additional, Natarajan, Iniyan, additional, Nathanail, Antonios, additional, Neilsen, Joey, additional, Neri, Roberto, additional, Ni, Chunchong, additional, Noutsos, Aristeidis, additional, Nowak, Michael A., additional, Oh, Junghwan, additional, Okino, Hiroki, additional, Olivares, Héctor, additional, Ortiz-León, Gisela N., additional, Oyama, Tomoaki, additional, Özel, Feryal, additional, Palumbo, Daniel C. M., additional, Paraschos, Georgios Filippos, additional, Park, Jongho, additional, Parsons, Harriet, additional, Patel, Nimesh, additional, Pesce, Dominic W., additional, Piétu, Vincent, additional, Plambeck, Richard, additional, PopStefanija, Aleksandar, additional, Porth, Oliver, additional, Pötzl, Felix M., additional, Prather, Ben, additional, Preciado-López, Jorge A., additional, Psaltis, Dimitrios, additional, Pu, Hung-Yi, additional, Ramakrishnan, Venkatessh, additional, Rao, Ramprasad, additional, Rawlings, Mark G., additional, Rezzolla, Luciano, additional, Ricarte, Angelo, additional, Ripperda, Bart, additional, Roelofs, Freek, additional, Rogers, Alan, additional, Ros, Eduardo, additional, Romero-Cañizales, Cristina, additional, Roshanineshat, Arash, additional, Roy, Alan L., additional, Ruszczyk, Chet, additional, Sánchez-Argüelles, David, additional, Sasada, Mahito, additional, Satapathy, Kaushik, additional, Savolainen, Tuomas, additional, Schloerb, F. Peter, additional, Schonfeld, Jonathan, additional, Small, Des, additional, Sohn, Bong Won, additional, SooHoo, Jason, additional, Souccar, Kamal, additional, Sun 孙, He 赫, additional, Tetarenko, Alexandra J., additional, Tiede, Paul, additional, Tilanus, Remo P. J., additional, Titus, Michael, additional, Toscano, Teresa, additional, Traianou, Efthalia, additional, Trent, Tyler, additional, Trippe, Sascha, additional, Turk, Matthew, additional, van Bemmel, Ilse, additional, van Langevelde, Huib Jan, additional, van Rossum, Daniel R., additional, Vos, Jesse, additional, Ward-Thompson, Derek, additional, Wardle, John, additional, Weintroub, Jonathan, additional, Wex, Norbert, additional, Wielgus, Maciek, additional, Wiik, Kaj, additional, Witzel, Gunther, additional, Wondrak, Michael F., additional, Wong, George N., additional, Wu 吴, Qingwen 庆文, additional, Yadlapalli, Nitika, additional, Yamaguchi, Paul, additional, Yfantis, Aristomenis, additional, Yoon, Doosoo, additional, Young, André, additional, Young, Ken, additional, Younsi, Ziri, additional, Yu 于, Wei 威, additional, Yuan 袁, Feng 峰, additional, Yuan 袁, Ye-Fei 业飞, additional, Zensus, J. Anton, additional, Zhang, Shuo, additional, Zhao, Guang-Yao, additional, and Zhao 赵, Shan-Shan 杉杉, additional

Published
2023
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26. Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes

Author

Roelofs, Freek, primary, Johnson, Michael D., additional, Chael, Andrew, additional, Janssen, Michael, additional, Wielgus, Maciek, additional, Broderick, Avery E., additional, Akiyama, Kazunori, additional, Alberdi, Antxon, additional, Alef, Walter, additional, Algaba, Juan Carlos, additional, Anantua, Richard, additional, Asada, Keiichi, additional, Azulay, Rebecca, additional, Bach, Uwe, additional, Baczko, Anne-Kathrin, additional, Ball, David, additional, Baloković, Mislav, additional, Barrett, John, additional, Bauböck, Michi, additional, Benson, Bradford A., additional, Bintley, Dan, additional, Blackburn, Lindy, additional, Blundell, Raymond, additional, Bouman, Katherine L., additional, Bower, Geoffrey C., additional, Boyce, Hope, additional, Bremer, Michael, additional, Brinkerink, Christiaan D., additional, Brissenden, Roger, additional, Britzen, Silke, additional, Broguiere, Dominique, additional, Bronzwaer, Thomas, additional, Bustamante, Sandra, additional, Byun, Do-Young, additional, Carlstrom, John E., additional, Ceccobello, Chiara, additional, Chan, Chi-kwan, additional, Chang, Dominic O., additional, Chatterjee, Koushik, additional, Chatterjee, Shami, additional, Chen, Ming-Tang, additional, Chen 陈, Yongjun 永军, additional, Cheng, Xiaopeng, additional, Cho, Ilje, additional, Christian, Pierre, additional, Conroy, Nicholas S., additional, Conway, John E., additional, Cordes, James M., additional, Crawford, Thomas M., additional, Crew, Geoffrey B., additional, Cruz-Osorio, Alejandro, additional, Cui 崔, Yuzhu 玉竹, additional, Dahale, Rohan, additional, Davelaar, Jordy, additional, De Laurentis, Mariafelicia, additional, Deane, Roger, additional, Dempsey, Jessica, additional, Desvignes, Gregory, additional, Dexter, Jason, additional, Dhruv, Vedant, additional, Doeleman, Sheperd S., additional, Dougal, Sean, additional, Dzib, Sergio A., additional, Eatough, Ralph P., additional, Emami, Razieh, additional, Falcke, Heino, additional, Farah, Joseph, additional, Fish, Vincent L., additional, Fomalont, Ed, additional, Ford, H. Alyson, additional, Foschi, Marianna, additional, Fraga-Encinas, Raquel, additional, Freeman, William T., additional, Friberg, Per, additional, Fromm, Christian M., additional, Fuentes, Antonio, additional, Galison, Peter, additional, Gammie, Charles F., additional, García, Roberto, additional, Gentaz, Olivier, additional, Georgiev, Boris, additional, Goddi, Ciriaco, additional, Gold, Roman, additional, Gómez-Ruiz, Arturo I., additional, Gómez, José L., additional, Gu 顾, Minfeng 敏峰, additional, Gurwell, Mark, additional, Hada, Kazuhiro, additional, Haggard, Daryl, additional, Haworth, Kari, additional, Hecht, Michael H., additional, Hesper, Ronald, additional, Heumann, Dirk, additional, Ho 何, Luis C. 子山, additional, Ho, Paul, additional, Honma, Mareki, additional, Huang, Chih-Wei L., additional, Huang 黄, Lei 磊, additional, Hughes, David H., additional, Ikeda, Shiro, additional, Impellizzeri, C. M. Violette, additional, Inoue, Makoto, additional, Issaoun, Sara, additional, James, David J., additional, Jannuzi, Buell T., additional, Jeter, Britton, additional, Jiang 江, Wu 悟, additional, Jiménez-Rosales, Alejandra, additional, Jorstad, Svetlana, additional, Joshi, Abhishek V., additional, Jung, Taehyun, additional, Karami, Mansour, additional, Karuppusamy, Ramesh, additional, Kawashima, Tomohisa, additional, Keating, Garrett K., additional, Kettenis, Mark, additional, Kim, Dong-Jin, additional, Kim, Jae-Young, additional, Kim, Jongsoo, additional, Kim, Junhan, additional, Kino, Motoki, additional, Koay, Jun Yi, additional, Kocherlakota, Prashant, additional, Kofuji, Yutaro, additional, Koch, Patrick M., additional, Koyama, Shoko, additional, Kramer, Carsten, additional, Kramer, Joana A., additional, Kramer, Michael, additional, Krichbaum, Thomas P., additional, Kuo, Cheng-Yu, additional, La Bella, Noemi, additional, Lauer, Tod R., additional, Lee, Daeyoung, additional, Lee, Sang-Sung, additional, Leung, Po Kin, additional, Levis, Aviad, additional, Li 李, Zhiyuan 志远, additional, Lico, Rocco, additional, Lindahl, Greg, additional, Lindqvist, Michael, additional, Lisakov, Mikhail, additional, Liu 刘, Jun 俊, additional, Liu, Kuo, additional, Liuzzo, Elisabetta, additional, Lo, Wen-Ping, additional, Lobanov, Andrei P., additional, Loinard, Laurent, additional, Lonsdale, Colin J., additional, Lowitz, Amy E., additional, Lu 路, Ru-Sen 如森, additional, MacDonald, Nicholas R., additional, Mao 毛, Jirong 基荣, additional, Marchili, Nicola, additional, Markoff, Sera, additional, Marrone, Daniel P., additional, Marscher, Alan P., additional, Martí-Vidal, Iván, additional, Matsushita, Satoki, additional, Matthews, Lynn D., additional, Medeiros, Lia, additional, Menten, Karl M., additional, Michalik, Daniel, additional, Mizuno, Izumi, additional, Mizuno, Yosuke, additional, Moran, James M., additional, Moriyama, Kotaro, additional, Moscibrodzka, Monika, additional, Mulaudzi, Wanga, additional, Müller, Cornelia, additional, Müller, Hendrik, additional, Mus, Alejandro, additional, Musoke, Gibwa, additional, Myserlis, Ioannis, additional, Nadolski, Andrew, additional, Nagai, Hiroshi, additional, Nagar, Neil M., additional, Nakamura, Masanori, additional, Narayan, Ramesh, additional, Narayanan, Gopal, additional, Natarajan, Iniyan, additional, Nathanail, Antonios, additional, Fuentes, Santiago Navarro, additional, Neilsen, Joey, additional, Neri, Roberto, additional, Ni, Chunchong, additional, Noutsos, Aristeidis, additional, Nowak, Michael A., additional, Oh, Junghwan, additional, Okino, Hiroki, additional, Olivares, Héctor, additional, Ortiz-León, Gisela N., additional, Oyama, Tomoaki, additional, Özel, Feryal, additional, Palumbo, Daniel C. M., additional, Paraschos, Georgios Filippos, additional, Park, Jongho, additional, Parsons, Harriet, additional, Patel, Nimesh, additional, Pen, Ue-Li, additional, Pesce, Dominic W., additional, Piétu, Vincent, additional, Plambeck, Richard, additional, PopStefanija, Aleksandar, additional, Porth, Oliver, additional, Pötzl, Felix M., additional, Prather, Ben, additional, Preciado-López, Jorge A., additional, Psaltis, Dimitrios, additional, Pu, Hung-Yi, additional, Ramakrishnan, Venkatessh, additional, Rao, Ramprasad, additional, Rawlings, Mark G., additional, Raymond, Alexander W., additional, Rezzolla, Luciano, additional, Ricarte, Angelo, additional, Ripperda, Bart, additional, Rogers, Alan, additional, Romero-Cañizales, Cristina, additional, Ros, Eduardo, additional, Roshanineshat, Arash, additional, Rottmann, Helge, additional, Roy, Alan L., additional, Ruiz, Ignacio, additional, Ruszczyk, Chet, additional, Rygl, Kazi L. J., additional, Sánchez, Salvador, additional, Sánchez-Argüelles, David, additional, Sánchez-Portal, Miguel, additional, Sasada, Mahito, additional, Satapathy, Kaushik, additional, Savolainen, Tuomas, additional, Schloerb, F. Peter, additional, Schonfeld, Jonathan, additional, Schuster, Karl-Friedrich, additional, Shao, Lijing, additional, Shen 沈, Zhiqiang 志强, additional, Small, Des, additional, Sohn, Bong Won, additional, SooHoo, Jason, additional, Sosapanta Salas, León David, additional, Souccar, Kamal, additional, Sun 孙, He 赫, additional, Tazaki, Fumie, additional, Tetarenko, Alexandra J., additional, Tiede, Paul, additional, Tilanus, Remo P. J., additional, Titus, Michael, additional, Torne, Pablo, additional, Toscano, Teresa, additional, Traianou, Efthalia, additional, Trent, Tyler, additional, Trippe, Sascha, additional, Turk, Matthew, additional, van Bemmel, Ilse, additional, van Langevelde, Huib Jan, additional, van Rossum, Daniel R., additional, Vos, Jesse, additional, Wagner, Jan, additional, Ward-Thompson, Derek, additional, Wardle, John, additional, Washington, Jasmin E., additional, Weintroub, Jonathan, additional, Wharton, Robert, additional, Wiik, Kaj, additional, Witzel, Gunther, additional, Wondrak, Michael F., additional, Wong, George N., additional, Wu 吴, Qingwen 庆文, additional, Yadlapalli, Nitika, additional, Yamaguchi, Paul, additional, Yfantis, Aristomenis, additional, Yoon, Doosoo, additional, Young, André, additional, Young, Ken, additional, Younsi, Ziri, additional, Yu 于, Wei 威, additional, Yuan 袁, Feng 峰, additional, Yuan 袁, Ye-Fei 业飞, additional, Zensus, J. Anton, additional, Zhang, Shuo, additional, Zhao, Guang-Yao, additional, and Zhao 赵, Shan-Shan 杉杉, additional

Published
2023
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27. Dealing with Behavior Problems: The Use of Positive Behavior Support Strategies in Summer Programs

Author

McKevitt, Brian C., Dempsey, Jessica N., and Ternus, Jackie

Abstract

Positive behavior support, with its emphasis on teaching desired actions rather than punishing undesirable actions, can be a powerful tool for managing young people's behavior. In recent years, positive behavior support (PBS) strategies have been promoted as alternatives to traditional discipline for children and youth. School use of PBS has been shown to significantly reduce the number of children referred to the office for discipline. It also allows administrators and teachers to regain time otherwise spent managing problem behaviors. Recently, PBS strategies have been applied outside the classroom in settings including playgrounds and summer recreation programs. Though implementing traditional school-based PBS in out-of-school time (OST) programs may present challenges, PBS offers an appropriate alternative to punishment-based behavior management. The authors' studies of PBS implementation in two community summer recreation programs suggest that PBS is a promising method for promoting desired behavior among children in OST programs. (Contains 3 figures and 1 table.)

Published
2012

28. SCUBA-2: on-sky calibration using submillimetre standard sources

Author

Dempsey, Jessica T., Friberg, Per, Jenness, Tim, Tilanus, Remo P. J., Thomas, Holly S., Holland, Wayne S., Bintley, Dan, Berry, David S., Chapin, Edward L., Chrysostomou, Antonio, Davis, Gary R., Gibb, Andrew G., Parsons, Harriet, and Robson, E. Ian

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

SCUBA-2 is a 10000-bolometer submillimetre camera on the James Clerk Maxwell Telescope (JCMT). The instrument commissioning was completed in September 2011, and full science operations began in October 2011. To harness the full potential of this powerful new astronomical tool, the instrument calibration must be accurate and well understood. To this end, the algorithms for calculating the line-of-sight opacity have been improved, and the derived atmospheric extinction relationships at both wavebands of the SCUBA-2 instrument are presented. The results from over 500 primary and secondary calibrator observations have allowed accurate determination of the flux conversion factors (FCF) for the 850 and 450 micron arrays. Descriptions of the instrument beam-shape and photometry methods are presented. The calibration factors are well determined, with relative calibration accuracy better than 5 per cent at 850 microns and 10 per cent at 450 microns, reflecting the success of the derived opacity relations as well as the stability of the performance of the instrument over several months. The sample-size of the calibration observations and accurate FCFs have allowed the determination of the 850 and 450 micron fluxes of several well-known submillimetre sources, and these results are compared with previous measurements from SCUBA., Comment: 12 pages, 18 figures, 4 tables, Accepted by MNRAS

Published
2013
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29. A new era of wide-field submillimetre imaging: on-sky performance of SCUBA-2

Author

Dempsey, Jessica T., Holland, Wayne S., Chrysostomou, Antonio, Berry, David S., Bintley, Daniel, Chapin, Edward L., Craig, Simon C., Coulson, Iain M., Davis, Gary R., Friberg, Per, Jenness, Tim, Gibb, Andy G., Parsons, Harriet A. L., Scott, Douglas, Thomas, Holly S., Tilanus, Remo P. J., Robson, Ian, and Walther, Craig A.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

SCUBA-2 is the largest submillimetre wide-field bolometric camera ever built. This 43 square arc-minute field-of-view instrument operates at two wavelengths (850 and 450 microns) and has been installed on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. SCUBA-2 has been successfully commissioned and operational for general science since October 2011. This paper presents an overview of the on-sky performance of the instrument during and since commissioning in mid-2011. The on-sky noise characteristics and NEPs of the 450 and 850 micron arrays, with average yields of approximately 3400 bolometers at each wavelength, will be shown. The observing modes of the instrument and the on-sky calibration techniques are described. The culmination of these efforts has resulted in a scientifically powerful mapping camera with sensitivities that allow a square degree of sky to be mapped to 10 mJy/beam rms at 850 micron in 2 hours and 60 mJy/beam rms at 450 micron in 5 hours in the best weather., Comment: 18 pages, 15 figures.SPIE Conference series 8452, Millimetre, Submillimetre and Far-infrared Detectors and Instrumentation for Astronomy VI 2012

Published
2012
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30. Extinction correction and on-sky calibration of SCUBA-2

Author

Dempsey, Jessica T., Friberg, Per, Jenness, Tim, Bintley, Dan, and Holland, Wayne S.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Commissioning of SCUBA-2 included a program of skydips and observations of calibration sources intended to be folded into regular observing as standard methods of source flux calibration and to monitor the atmospheric opacity and stability. During commissioning, it was found that these methods could also be utilised to characterise the fundamental instrument response to sky noise and astronomical signals. Novel techniques for analysing on-sky performance and atmospheric conditions are presented, along with results from the calibration observations and skydips., Comment: 10 pages, 7 figures

Published
2010
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31. The Greenland Telescope—Construction, Commissioning, and Operations in Pituffik

Author

Chen, Ming-Tang, primary, Asada, Keiichi, additional, Matsushita, Satoki, additional, Raffin, Philippe, additional, Inoue, Makoto, additional, Ho, Paul T. P., additional, Han, Chih-Chiang, additional, Kubo, Derek, additional, Norton, Timothy, additional, Patel, Nimesh A., additional, Nystrom, George, additional, Huang, Chih-Wei L., additional, Martin-Cocher, Pierre, additional, Yi Koay, Jun, additional, Romero-Cañizales, Cristina, additional, Liu, Ching-Tang, additional, Huang, Teddy, additional, Liu, Kuan-Yu, additional, Wei, Tashun, additional, Chang, Shu-Hao, additional, Chilson, Ryan, additional, Oshiro, Peter, additional, Jiang, Homin, additional, Li, Chao-Te, additional, Bower, Geoffrey, additional, Shaw, Paul, additional, Nishioka, Hiroaki, additional, Koch, Patrick M., additional, Chen, Chung-Cheng, additional, Srinivasan, Ranjani, additional, Rao, Ramprasad, additional, Snow, William, additional, Jinchi, Hao, additional, Han, Kuo-Chang, additional, Chang, Song-Chu, additional, Lu, Li-Ming, additional, Ogawa, Hideo, additional, Kimura, Kimihiro, additional, Hasegawa, Yutaka, additional, Pu, Hung-Yi, additional, Koyama, Shoko, additional, Nakamura, Masanori, additional, Bintley, Daniel, additional, Walther, Craig, additional, Friberg, Per, additional, Dempsey, Jessica, additional, Sriharan, T. K., additional, Srikanth, Sivasankaran, additional, Doeleman, Sheperd S., additional, Brissenden, Roger, additional, Algaba Marcos, Juan-Carlos, additional, Jeter, Britt, additional, Kuo, Cheng-Yu, additional, and Park, Jongho, additional

Published
2023
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32. Nature–Culture

Author

Sundberg, Juanita, primary, Dempsey, Jessica, additional, and Marchini, Fernanda Rojas, additional

Published
2020
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34. Giving Form to Consciousness.

Author

Dempsey, Jessica

Subjects
*CLIMATE change education, *CONSCIOUSNESS, *ARGUMENT
Abstract

Engaging Debbie Hopkin's arguments on fly less or no fly movements, this essay reflects on faculty efforts to reduce aviation-related emissions at the University of British Columbia. [ABSTRACT FROM AUTHOR]

Published
2024

36. Comparison of Polarized Radiative Transfer Codes Used by the EHT Collaboration

Author

Prather, Ben S., primary, Dexter, Jason, additional, Moscibrodzka, Monika, additional, Pu, Hung-Yi, additional, Bronzwaer, Thomas, additional, Davelaar, Jordy, additional, Younsi, Ziri, additional, Gammie, Charles F., additional, Gold, Roman, additional, Wong, George N., additional, Akiyama, Kazunori, additional, Alberdi, Antxon, additional, Alef, Walter, additional, Algaba, Juan Carlos, additional, Anantua, Richard, additional, Asada, Keiichi, additional, Azulay, Rebecca, additional, Bach, Uwe, additional, Baczko, Anne-Kathrin, additional, Ball, David, additional, Baloković, Mislav, additional, Barrett, John, additional, Bauböck, Michi, additional, Benson, Bradford A., additional, Bintley, Dan, additional, Blackburn, Lindy, additional, Blundell, Raymond, additional, Bouman, Katherine L., additional, Bower, Geoffrey C., additional, Boyce, Hope, additional, Bremer, Michael, additional, Brinkerink, Christiaan D., additional, Brissenden, Roger, additional, Britzen, Silke, additional, Broderick, Avery E., additional, Broguiere, Dominique, additional, Bustamante, Sandra, additional, Byun, Do-Young, additional, Carlstrom, John E., additional, Ceccobello, Chiara, additional, Chael, Andrew, additional, Chan, Chi-kwan, additional, Chang, Dominic O., additional, Chatterjee, Koushik, additional, Chatterjee, Shami, additional, Chen, Ming-Tang, additional, Chen, Yongjun, additional, Cheng, Xiaopeng, additional, Cho, Ilje, additional, Christian, Pierre, additional, Conroy, Nicholas S., additional, Conway, John E., additional, Cordes, James M., additional, Crawford, Thomas M., additional, Crew, Geoffrey B., additional, Cruz-Osorio, Alejandro, additional, Cui, Yuzhu, additional, De Laurentis, Mariafelicia, additional, Deane, Roger, additional, Dempsey, Jessica, additional, Desvignes, Gregory, additional, Dhruv, Vedant, additional, Doeleman, Sheperd S., additional, Dougal, Sean, additional, Dzib, Sergio A., additional, Eatough, Ralph P., additional, Emami, Razieh, additional, Falcke, Heino, additional, Farah, Joseph, additional, Fish, Vincent L., additional, Fomalont, Ed, additional, Ford, H. Alyson, additional, Fraga-Encinas, Raquel, additional, Freeman, William T., additional, Friberg, Per, additional, Fromm, Christian M., additional, Fuentes, Antonio, additional, Galison, Peter, additional, García, Roberto, additional, Gentaz, Olivier, additional, Georgiev, Boris, additional, Goddi, Ciriaco, additional, Gómez-Ruiz, Arturo I., additional, Gómez, José L., additional, Gu, Minfeng, additional, Gurwell, Mark, additional, Hada, Kazuhiro, additional, Haggard, Daryl, additional, Haworth, Kari, additional, Hecht, Michael H., additional, Hesper, Ronald, additional, Heumann, Dirk, additional, Ho, Luis C., additional, Ho, Paul, additional, Honma, Mareki, additional, Huang, Chih-Wei L., additional, Huang, Lei, additional, Hughes, David H., additional, Ikeda, Shiro, additional, Impellizzeri, C. M. Violette, additional, Inoue, Makoto, additional, Issaoun, Sara, additional, James, David J., additional, Jannuzi, Buell T., additional, Janssen, Michael, additional, Jeter, Britton, additional, Jiang, Wu, additional, Jiménez-Rosales, Alejandra, additional, Johnson, Michael D., additional, Jorstad, Svetlana, additional, Joshi, Abhishek V., additional, Jung, Taehyun, additional, Karami, Mansour, additional, Karuppusamy, Ramesh, additional, Kawashima, Tomohisa, additional, Keating, Garrett K., additional, Kettenis, Mark, additional, Kim, Dong-Jin, additional, Kim, Jae-Young, additional, Kim, Jongsoo, additional, Kim, Junhan, additional, Kino, Motoki, additional, Koay, Jun Yi, additional, Kocherlakota, Prashant, additional, Kofuji, Yutaro, additional, Koyama, Shoko, additional, Kramer, Carsten, additional, Kramer, Michael, additional, Krichbaum, Thomas P., additional, Kuo, Cheng-Yu, additional, La Bella, Noemi, additional, Lauer, Tod R., additional, Lee, Daeyoung, additional, Lee, Sang-Sung, additional, Leung, Po Kin, additional, Levis, Aviad, additional, Li, Zhiyuan, additional, Lico, Rocco, additional, Lindahl, Greg, additional, Lindqvist, Michael, additional, Lisakov, Mikhail, additional, Liu, Jun, additional, Liu, Kuo, additional, Liuzzo, Elisabetta, additional, Lo, Wen-Ping, additional, Lobanov, Andrei P., additional, Loinard, Laurent, additional, Lonsdale, Colin J., additional, Lu, Ru-Sen, additional, MacDonald, Nicholas R., additional, Mao, Jirong, additional, Marchili, Nicola, additional, Markoff, Sera, additional, Marrone, Daniel P., additional, Marscher, Alan P., additional, Martí-Vidal, Iván, additional, Matsushita, Satoki, additional, Matthews, Lynn D., additional, Medeiros, Lia, additional, Menten, Karl M., additional, Michalik, Daniel, additional, Mizuno, Izumi, additional, Mizuno, Yosuke, additional, Moran, James M., additional, Moriyama, Kotaro, additional, Müller, Cornelia, additional, Mus, Alejandro, additional, Musoke, Gibwa, additional, Myserlis, Ioannis, additional, Nadolski, Andrew, additional, Nagai, Hiroshi, additional, Nagar, Neil M., additional, Nakamura, Masanori, additional, Narayan, Ramesh, additional, Narayanan, Gopal, additional, Natarajan, Iniyan, additional, Nathanail, Antonios, additional, Fuentes, Santiago Navarro, additional, Neilsen, Joey, additional, Neri, Roberto, additional, Ni, Chunchong, additional, Noutsos, Aristeidis, additional, Nowak, Michael A., additional, Oh, Junghwan, additional, Okino, Hiroki, additional, Olivares, Héctor, additional, Ortiz-León, Gisela N., additional, Oyama, Tomoaki, additional, Özel, Feryal, additional, Palumbo, Daniel C. M., additional, Paraschos, Georgios Filippos, additional, Park, Jongho, additional, Parsons, Harriet, additional, Patel, Nimesh, additional, Pen, Ue-Li, additional, Pesce, Dominic W., additional, Piétu, Vincent, additional, Plambeck, Richard, additional, PopStefanija, Aleksandar, additional, Porth, Oliver, additional, Pötzl, Felix M., additional, Preciado-López, Jorge A., additional, Psaltis, Dimitrios, additional, Ramakrishnan, Venkatessh, additional, Rao, Ramprasad, additional, Rawlings, Mark G., additional, Raymond, Alexander W., additional, Rezzolla, Luciano, additional, Ricarte, Angelo, additional, Ripperda, Bart, additional, Roelofs, Freek, additional, Rogers, Alan, additional, Ros, Eduardo, additional, Romero-Cañizales, Cristina, additional, Roshanineshat, Arash, additional, Rottmann, Helge, additional, Roy, Alan L., additional, Ruiz, Ignacio, additional, Ruszczyk, Chet, additional, Rygl, Kazi L. J., additional, Sánchez, Salvador, additional, Sánchez-Argüelles, David, additional, Sánchez-Portal, Miguel, additional, Sasada, Mahito, additional, Satapathy, Kaushik, additional, Savolainen, Tuomas, additional, Schloerb, F. Peter, additional, Schonfeld, Jonathan, additional, Schuster, Karl-Friedrich, additional, Shao, Lijing, additional, Shen, Zhiqiang, additional, Small, Des, additional, Sohn, Bong Won, additional, SooHoo, Jason, additional, Souccar, Kamal, additional, Sun, He, additional, Tazaki, Fumie, additional, Tetarenko, Alexandra J., additional, Tiede, Paul, additional, Tilanus, Remo P. J., additional, Titus, Michael, additional, Torne, Pablo, additional, Traianou, Efthalia, additional, Trent, Tyler, additional, Trippe, Sascha, additional, Turk, Matthew, additional, van Bemmel, Ilse, additional, van Langevelde, Huib Jan, additional, van Rossum, Daniel R., additional, Vos, Jesse, additional, Wagner, Jan, additional, Ward-Thompson, Derek, additional, Wardle, John, additional, Weintroub, Jonathan, additional, Wex, Norbert, additional, Wharton, Robert, additional, Wielgus, Maciek, additional, Wiik, Kaj, additional, Witzel, Gunther, additional, Wondrak, Michael F., additional, Wu, Qingwen, additional, Yamaguchi, Paul, additional, Yfantis, Aristomenis, additional, Yoon, Doosoo, additional, Young, André, additional, Young, Ken, additional, Yu, Wei, additional, Yuan, Feng, additional, Yuan, Ye-Fei, additional, Zensus, J. Anton, additional, Zhang, Shuo, additional, Zhao, Guang-Yao, additional, and Zhao, Shan-Shan, additional

Published
2023
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38. A ring-like accretion structure in M87 connecting its black hole and jet

Author

Lu, Ru-Sen, primary, Asada, Keiichi, additional, Krichbaum, Thomas P., additional, Park, Jongho, additional, Tazaki, Fumie, additional, Pu, Hung-Yi, additional, Nakamura, Masanori, additional, Lobanov, Andrei, additional, Hada, Kazuhiro, additional, Akiyama, Kazunori, additional, Kim, Jae-Young, additional, Marti-Vidal, Ivan, additional, Gómez, José L., additional, Kawashima, Tomohisa, additional, Yuan, Feng, additional, Ros, Eduardo, additional, Alef, Walter, additional, Britzen, Silke, additional, Bremer, Michael, additional, Broderick, Avery E., additional, Doi, Akihiro, additional, Giovannini, Gabriele, additional, Giroletti, Marcello, additional, Ho, Paul T. P., additional, Honma, Mareki, additional, Hughes, David H., additional, Inoue, Makoto, additional, Jiang, Wu, additional, Kino, Motoki, additional, Koyama, Shoko, additional, Lindqvist, Michael, additional, Liu, Jun, additional, Marscher, Alan P., additional, Matsushita, Satoki, additional, Nagai, Hiroshi, additional, Rottmann, Helge, additional, Savolainen, Tuomas, additional, Schuster, Karl-Friedrich, additional, Shen, Zhi-Qiang, additional, de Vicente, Pablo, additional, Walker, R. Craig, additional, Yang, Hai, additional, Zensus, J. Anton, additional, Algaba, Juan Carlos, additional, Allardi, Alexander, additional, Bach, Uwe, additional, Berthold, Ryan, additional, Bintley, Dan, additional, Byun, Do-Young, additional, Casadio, Carolina, additional, Chang, Shu-Hao, additional, Chang, Chih-Cheng, additional, Chang, Song-Chu, additional, Chen, Chung-Chen, additional, Chen, Ming-Tang, additional, Chilson, Ryan, additional, Chuter, Tim C., additional, Conway, John, additional, Crew, Geoffrey B., additional, Dempsey, Jessica T., additional, Dornbusch, Sven, additional, Faber, Aaron, additional, Friberg, Per, additional, García, Javier González, additional, Garrido, Miguel Gómez, additional, Han, Chih-Chiang, additional, Han, Kuo-Chang, additional, Hasegawa, Yutaka, additional, Herrero-Illana, Ruben, additional, Huang, Yau-De, additional, Huang, Chih-Wei L., additional, Impellizzeri, Violette, additional, Jiang, Homin, additional, Jinchi, Hao, additional, Jung, Taehyun, additional, Kallunki, Juha, additional, Kirves, Petri, additional, Kimura, Kimihiro, additional, Koay, Jun Yi, additional, Koch, Patrick M., additional, Kramer, Carsten, additional, Kraus, Alex, additional, Kubo, Derek, additional, Kuo, Cheng-Yu, additional, Li, Chao-Te, additional, Lin, Lupin Chun-Che, additional, Liu, Ching-Tang, additional, Liu, Kuan-Yu, additional, Lo, Wen-Ping, additional, Lu, Li-Ming, additional, MacDonald, Nicholas, additional, Martin-Cocher, Pierre, additional, Messias, Hugo, additional, Meyer-Zhao, Zheng, additional, Minter, Anthony, additional, Nair, Dhanya G., additional, Nishioka, Hiroaki, additional, Norton, Timothy J., additional, Nystrom, George, additional, Ogawa, Hideo, additional, Oshiro, Peter, additional, Patel, Nimesh A., additional, Pen, Ue-Li, additional, Pidopryhora, Yurii, additional, Pradel, Nicolas, additional, Raffin, Philippe A., additional, Rao, Ramprasad, additional, Ruiz, Ignacio, additional, Sanchez, Salvador, additional, Shaw, Paul, additional, Snow, William, additional, Sridharan, T. K., additional, Srinivasan, Ranjani, additional, Tercero, Belén, additional, Torne, Pablo, additional, Traianou, Efthalia, additional, Wagner, Jan, additional, Walther, Craig, additional, Wei, Ta-Shun, additional, Yang, Jun, additional, and Yu, Chen-Yu, additional

Published
2023
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39. The Event Horizon Telescope Image of the Quasar NRAO 530

Author

Jorstad, Svetlana, primary, Wielgus, Maciek, additional, Lico, Rocco, additional, Issaoun, Sara, additional, Broderick, Avery E., additional, Pesce, Dominic W., additional, Liu, Jun, additional, Zhao, Guang-Yao, additional, Krichbaum, Thomas P., additional, Blackburn, Lindy, additional, Chan, Chi-kwan, additional, Janssen, Michael, additional, Ramakrishnan, Venkatessh, additional, Akiyama, Kazunori, additional, Alberdi, Antxon, additional, Algaba, Juan Carlos, additional, Bouman, Katherine L., additional, Cho, Ilje, additional, Fuentes, Antonio, additional, Gómez, José L., additional, Gurwell, Mark, additional, Johnson, Michael D., additional, Kim, Jae-Young, additional, Lu, Ru-Sen, additional, Martí-Vidal, Iván, additional, Moscibrodzka, Monika, additional, Pötzl, Felix M., additional, Traianou, Efthalia, additional, van Bemmel, Ilse, additional, Alef, Walter, additional, Anantua, Richard, additional, Asada, Keiichi, additional, Azulay, Rebecca, additional, Bach, Uwe, additional, Baczko, Anne-Kathrin, additional, Ball, David, additional, Baloković, Mislav, additional, Barrett, John, additional, Bauböck, Michi, additional, Benson, Bradford A., additional, Bintley, Dan, additional, Blundell, Raymond, additional, Bower, Geoffrey C., additional, Boyce, Hope, additional, Bremer, Michael, additional, Brinkerink, Christiaan D., additional, Brissenden, Roger, additional, Britzen, Silke, additional, Broguiere, Dominique, additional, Bronzwaer, Thomas, additional, Bustamante, Sandra, additional, Byun, Do-Young, additional, Carlstrom, John E., additional, Ceccobello, Chiara, additional, Chael, Andrew, additional, Chatterjee, Koushik, additional, Chatterjee, Shami, additional, Chen, Ming-Tang, additional, Chen, Yongjun, additional, Cheng, Xiaopeng, additional, Christian, Pierre, additional, Conroy, Nicholas S., additional, Conway, John E., additional, Cordes, James M., additional, Crawford, Thomas M., additional, Crew, Geoffrey B., additional, Cruz-Osorio, Alejandro, additional, Cui, Yuzhu, additional, Davelaar, Jordy, additional, De Laurentis, Mariafelicia, additional, Deane, Roger, additional, Dempsey, Jessica, additional, Desvignes, Gregory, additional, Dexter, Jason, additional, Dhruv, Vedant, additional, Doeleman, Sheperd S., additional, Dougal, Sean, additional, Dzib, Sergio A., additional, Eatough, Ralph P., additional, Emami, Razieh, additional, Falcke, Heino, additional, Farah, Joseph, additional, Fish, Vincent L., additional, Fomalont, Ed, additional, Ford, H. Alyson, additional, Fraga-Encinas, Raquel, additional, Freeman, William T., additional, Friberg, Per, additional, Fromm, Christian M., additional, Galison, Peter, additional, Gammie, Charles F., additional, García, Roberto, additional, Gentaz, Olivier, additional, Georgiev, Boris, additional, Goddi, Ciriaco, additional, Gold, Roman, additional, Gómez-Ruiz, Arturo I., additional, Gu, Minfeng, additional, Hada, Kazuhiro, additional, Haggard, Daryl, additional, Haworth, Kari, additional, Hecht, Michael H., additional, Hesper, Ronald, additional, Heumann, Dirk, additional, Ho, Luis C., additional, Ho, Paul, additional, Honma, Mareki, additional, Huang, Chih-Wei L., additional, Huang, Lei, additional, Hughes, David H., additional, Ikeda, Shiro, additional, Impellizzeri, C. M. Violette, additional, Inoue, Makoto, additional, James, David J., additional, Jannuzi, Buell T., additional, Jeter, Britton, additional, Jiang, Wu, additional, Jiménez-Rosales, Alejandra, additional, Joshi, Abhishek V., additional, Jung, Taehyun, additional, Karami, Mansour, additional, Karuppusamy, Ramesh, additional, Kawashima, Tomohisa, additional, Keating, Garrett K., additional, Kettenis, Mark, additional, Kim, Dong-Jin, additional, Kim, Jongsoo, additional, Kim, Junhan, additional, Kino, Motoki, additional, Koay, Jun Yi, additional, Kocherlakota, Prashant, additional, Kofuji, Yutaro, additional, Koyama, Shoko, additional, Kramer, Carsten, additional, Kramer, Michael, additional, Kuo, Cheng-Yu, additional, La Bella, Noemi, additional, Lauer, Tod R., additional, Lee, Daeyoung, additional, Lee, Sang-Sung, additional, Leung, Po Kin, additional, Levis, Aviad, additional, Li, Zhiyuan, additional, Lindahl, Greg, additional, Lindqvist, Michael, additional, Lisakov, Mikhail, additional, Liu, Kuo, additional, Liuzzo, Elisabetta, additional, Lo, Wen-Ping, additional, Lobanov, Andrei P., additional, Loinard, Laurent, additional, Lonsdale, Colin J., additional, MacDonald, Nicholas R., additional, Mao, Jirong, additional, Marchili, Nicola, additional, Markoff, Sera, additional, Marrone, Daniel P., additional, Marscher, Alan P., additional, Matsushita, Satoki, additional, Matthews, Lynn D., additional, Medeiros, Lia, additional, Menten, Karl M., additional, Michalik, Daniel, additional, Mizuno, Izumi, additional, Mizuno, Yosuke, additional, Moran, James M., additional, Moriyama, Kotaro, additional, Müller, Cornelia, additional, Mus, Alejandro, additional, Musoke, Gibwa, additional, Myserlis, Ioannis, additional, Nadolski, Andrew, additional, Nagai, Hiroshi, additional, Nagar, Neil M., additional, Nakamura, Masanori, additional, Narayan, Ramesh, additional, Narayanan, Gopal, additional, Natarajan, Iniyan, additional, Nathanail, Antonios, additional, Fuentes, Santiago Navarro, additional, Neilsen, Joey, additional, Neri, Roberto, additional, Ni, Chunchong, additional, Noutsos, Aristeidis, additional, Nowak, Michael A., additional, Oh, Junghwan, additional, Okino, Hiroki, additional, Olivares, Héctor, additional, Ortiz-León, Gisela N., additional, Oyama, Tomoaki, additional, Özel, Feryal, additional, Palumbo, Daniel C. M., additional, Paraschos, Georgios Filippos, additional, Park, Jongho, additional, Parsons, Harriet, additional, Patel, Nimesh, additional, Pen, Ue-Li, additional, Piétu, Vincent, additional, Plambeck, Richard, additional, PopStefanija, Aleksandar, additional, Porth, Oliver, additional, Prather, Ben, additional, Preciado-López, Jorge A., additional, Psaltis, Dimitrios, additional, Pu, Hung-Yi, additional, Rao, Ramprasad, additional, Rawlings, Mark G., additional, Raymond, Alexander W., additional, Rezzolla, Luciano, additional, Ricarte, Angelo, additional, Ripperda, Bart, additional, Roelofs, Freek, additional, Rogers, Alan, additional, Ros, Eduardo, additional, Romero-Cañizales, Cristina, additional, Roshanineshat, Arash, additional, Rottmann, Helge, additional, Roy, Alan L., additional, Ruiz, Ignacio, additional, Ruszczyk, Chet, additional, Rygl, Kazi L. J., additional, Sánchez, Salvador, additional, Sánchez-Argüelles, David, additional, Sánchez-Portal, Miguel, additional, Sasada, Mahito, additional, Satapathy, Kaushik, additional, Savolainen, Tuomas, additional, Schloerb, F. Peter, additional, Schonfeld, Jonathan, additional, Schuster, Karl-Friedrich, additional, Shao, Lijing, additional, Shen, Zhiqiang, additional, Small, Des, additional, Sohn, Bong Won, additional, SooHoo, Jason, additional, Souccar, Kamal, additional, Sun, He, additional, Tazaki, Fumie, additional, Tetarenko, Alexandra J., additional, Tiede, Paul, additional, Tilanus, Remo P. J., additional, Titus, Michael, additional, Torne, Pablo, additional, Trent, Tyler, additional, Trippe, Sascha, additional, Turk, Matthew, additional, van Langevelde, Huib Jan, additional, van Rossum, Daniel R., additional, Vos, Jesse, additional, Wagner, Jan, additional, Ward-Thompson, Derek, additional, Wardle, John, additional, Weintroub, Jonathan, additional, Wex, Norbert, additional, Wharton, Robert, additional, Wiik, Kaj, additional, Witzel, Gunther, additional, Wondrak, Michael F., additional, Wong, George N., additional, Wu, Qingwen, additional, Yamaguchi, Paul, additional, Yoon, Doosoo, additional, Young, André, additional, Young, Ken, additional, Younsi, Ziri, additional, Yuan, Feng, additional, Yuan, Ye-Fei, additional, Zensus, J. Anton, additional, Zhang, Shuo, additional, and Zhao, Shan-Shan, additional

Published
2023
Full Text
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40. Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes

Author

Roelofs, Freek, Johnson, Michael D., Chael, Andrew, Janssen, Michael, Wielgus, Maciek, Broderick, Avery E., Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Bach, Uwe, Baczko, Anne-Kathrin, Ball, David, Baloković, Mislav, Barrett, John, Bauböck, Michi, Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Bouman, Katherine L., Bower, Geoffrey C., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broguiere, Dominique, Bronzwaer, Thomas, Bustamante, Sandra, Byun, Do-Young, Carlstrom, John E., Ceccobello, Chiara, Chan, Chi-kwan, Chang, Dominic O., Chatterjee, Koushik, Chatterjee, Shami, Chen, Ming-Tang, Chen, Yongjun, Cheng, Xiaopeng, Cho, Ilje, Christian, Pierre, Conroy, Nicholas S., Conway, John E., Cordes, James M., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, Dahale, Rohan, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Dexter, Jason, Dhruv, Vedant, Doeleman, Sheperd S., Dougal, Sean, Dzib, Sergio A., Eatough, Ralph P., Emami, Razieh, Falcke, Heino, Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Ford, H. Alyson, Foschi, Marianna, Fraga-Encinas, Raquel, Freeman, William T., Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, Gammie, Charles F., García, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, Ciriaco, Gold, Roman, Gómez-Ruiz, Arturo I., Gómez, José L., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Haworth, Kari, Hecht, Michael H., Hesper, Ronald, Heumann, Dirk, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Impellizzeri, C. M. Violette, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Jeter, Britton, Jiang, Wu, Jiménez-Rosales, Alejandra, Jorstad, Svetlana, Joshi, Abhishek V., Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kocherlakota, Prashant, Kofuji, Yutaro, Koch, Patrick M., Koyama, Shoko, Kramer, Carsten, Kramer, Joana A., Kramer, Michael, Krichbaum, Thomas P., Kuo, Cheng-Yu, La Bella, Noemi, Lauer, Tod R., Lee, Daeyoung, Lee, Sang-Sung, Leung, Po Kin, Levis, Aviad, Li, Zhiyuan, Lico, Rocco, Lindahl, Greg, Lindqvist, Michael, Lisakov, Mikhail, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lo, Wen-Ping, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin J., Lowitz, Amy E., Lu, Ru-Sen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Martí-Vidal, Iván, Matsushita, Satoki, Matthews, Lynn D., Medeiros, Lia, Menten, Karl M., Michalik, Daniel, Mizuno, Izumi, Mizuno, Yosuke, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Mulaudzi, Wanga, Müller, Cornelia, Müller, Hendrik, Mus, Alejandro, Musoke, Gibwa, Myserlis, Ioannis, Nadolski, Andrew, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Fuentes, Santiago Navarro, Neilsen, Joey, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Oh, Junghwan, Okino, Hiroki, Olivares, Héctor, Ortiz-León, Gisela N., Oyama, Tomoaki, Özel, Feryal, Palumbo, Daniel C. M., Paraschos, Georgios Filippos, Park, Jongho, Parsons, Harriet, Patel, Nimesh, Pen, Ue-Li, Pesce, Dominic W., Piétu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Pötzl, Felix M., Prather, Ben, Preciado-López, Jorge A., Psaltis, Dimitrios, Pu, Hung-Yi, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Rezzolla, Luciano, Ricarte, Angelo, Ripperda, Bart, Rogers, Alan, Romero-Cañizales, Cristina, Ros, Eduardo, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruiz, Ignacio, Ruszczyk, Chet, Rygl, Kazi L. J., Sánchez, Salvador, Sánchez-Argüelles, David, Sánchez-Portal, Miguel, Sasada, Mahito, Satapathy, Kaushik, Savolainen, Tuomas, Schloerb, F. Peter, Schonfeld, Jonathan, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Sosapanta Salas, León David, Souccar, Kamal, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Torne, Pablo, Toscano, Teresa, Traianou, Efthalia, Trent, Tyler, Trippe, Sascha, Turk, Matthew, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Vos, Jesse, Wagner, Jan, Ward-Thompson, Derek, Wardle, John, Washington, Jasmin E., Weintroub, Jonathan, Wharton, Robert, Wiik, Kaj, Witzel, Gunther, Wondrak, Michael F., Wong, George N., Wu, Qingwen, Yadlapalli, Nitika, Yamaguchi, Paul, Yfantis, Aristomenis, Yoon, Doosoo, Young, André, Young, Ken, Younsi, Ziri, Yu, Wei, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhang, Shuo, Zhao, Guang-Yao, Zhao, Shan-Shan, Roelofs, Freek, Johnson, Michael D., Chael, Andrew, Janssen, Michael, Wielgus, Maciek, Broderick, Avery E., Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, Azulay, Rebecca, Bach, Uwe, Baczko, Anne-Kathrin, Ball, David, Baloković, Mislav, Barrett, John, Bauböck, Michi, Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Bouman, Katherine L., Bower, Geoffrey C., Boyce, Hope, Bremer, Michael, Brinkerink, Christiaan D., Brissenden, Roger, Britzen, Silke, Broguiere, Dominique, Bronzwaer, Thomas, Bustamante, Sandra, Byun, Do-Young, Carlstrom, John E., Ceccobello, Chiara, Chan, Chi-kwan, Chang, Dominic O., Chatterjee, Koushik, Chatterjee, Shami, Chen, Ming-Tang, Chen, Yongjun, Cheng, Xiaopeng, Cho, Ilje, Christian, Pierre, Conroy, Nicholas S., Conway, John E., Cordes, James M., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, Dahale, Rohan, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Dempsey, Jessica, Desvignes, Gregory, Dexter, Jason, Dhruv, Vedant, Doeleman, Sheperd S., Dougal, Sean, Dzib, Sergio A., Eatough, Ralph P., Emami, Razieh, Falcke, Heino, Farah, Joseph, Fish, Vincent L., Fomalont, Ed, Ford, H. Alyson, Foschi, Marianna, Fraga-Encinas, Raquel, Freeman, William T., Friberg, Per, Fromm, Christian M., Fuentes, Antonio, Galison, Peter, Gammie, Charles F., García, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, Ciriaco, Gold, Roman, Gómez-Ruiz, Arturo I., Gómez, José L., Gu, Minfeng, Gurwell, Mark, Hada, Kazuhiro, Haggard, Daryl, Haworth, Kari, Hecht, Michael H., Hesper, Ronald, Heumann, Dirk, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih-Wei L., Huang, Lei, Hughes, David H., Ikeda, Shiro, Impellizzeri, C. M. Violette, Inoue, Makoto, Issaoun, Sara, James, David J., Jannuzi, Buell T., Jeter, Britton, Jiang, Wu, Jiménez-Rosales, Alejandra, Jorstad, Svetlana, Joshi, Abhishek V., Jung, Taehyun, Karami, Mansour, Karuppusamy, Ramesh, Kawashima, Tomohisa, Keating, Garrett K., Kettenis, Mark, Kim, Dong-Jin, Kim, Jae-Young, Kim, Jongsoo, Kim, Junhan, Kino, Motoki, Koay, Jun Yi, Kocherlakota, Prashant, Kofuji, Yutaro, Koch, Patrick M., Koyama, Shoko, Kramer, Carsten, Kramer, Joana A., Kramer, Michael, Krichbaum, Thomas P., Kuo, Cheng-Yu, La Bella, Noemi, Lauer, Tod R., Lee, Daeyoung, Lee, Sang-Sung, Leung, Po Kin, Levis, Aviad, Li, Zhiyuan, Lico, Rocco, Lindahl, Greg, Lindqvist, Michael, Lisakov, Mikhail, Liu, Jun, Liu, Kuo, Liuzzo, Elisabetta, Lo, Wen-Ping, Lobanov, Andrei P., Loinard, Laurent, Lonsdale, Colin J., Lowitz, Amy E., Lu, Ru-Sen, MacDonald, Nicholas R., Mao, Jirong, Marchili, Nicola, Markoff, Sera, Marrone, Daniel P., Marscher, Alan P., Martí-Vidal, Iván, Matsushita, Satoki, Matthews, Lynn D., Medeiros, Lia, Menten, Karl M., Michalik, Daniel, Mizuno, Izumi, Mizuno, Yosuke, Moran, James M., Moriyama, Kotaro, Moscibrodzka, Monika, Mulaudzi, Wanga, Müller, Cornelia, Müller, Hendrik, Mus, Alejandro, Musoke, Gibwa, Myserlis, Ioannis, Nadolski, Andrew, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayanan, Gopal, Natarajan, Iniyan, Nathanail, Antonios, Fuentes, Santiago Navarro, Neilsen, Joey, Neri, Roberto, Ni, Chunchong, Noutsos, Aristeidis, Nowak, Michael A., Oh, Junghwan, Okino, Hiroki, Olivares, Héctor, Ortiz-León, Gisela N., Oyama, Tomoaki, Özel, Feryal, Palumbo, Daniel C. M., Paraschos, Georgios Filippos, Park, Jongho, Parsons, Harriet, Patel, Nimesh, Pen, Ue-Li, Pesce, Dominic W., Piétu, Vincent, Plambeck, Richard, PopStefanija, Aleksandar, Porth, Oliver, Pötzl, Felix M., Prather, Ben, Preciado-López, Jorge A., Psaltis, Dimitrios, Pu, Hung-Yi, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Raymond, Alexander W., Rezzolla, Luciano, Ricarte, Angelo, Ripperda, Bart, Rogers, Alan, Romero-Cañizales, Cristina, Ros, Eduardo, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruiz, Ignacio, Ruszczyk, Chet, Rygl, Kazi L. J., Sánchez, Salvador, Sánchez-Argüelles, David, Sánchez-Portal, Miguel, Sasada, Mahito, Satapathy, Kaushik, Savolainen, Tuomas, Schloerb, F. Peter, Schonfeld, Jonathan, Schuster, Karl-Friedrich, Shao, Lijing, Shen, Zhiqiang, Small, Des, Sohn, Bong Won, SooHoo, Jason, Sosapanta Salas, León David, Souccar, Kamal, Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tiede, Paul, Tilanus, Remo P. J., Titus, Michael, Torne, Pablo, Toscano, Teresa, Traianou, Efthalia, Trent, Tyler, Trippe, Sascha, Turk, Matthew, van Bemmel, Ilse, van Langevelde, Huib Jan, van Rossum, Daniel R., Vos, Jesse, Wagner, Jan, Ward-Thompson, Derek, Wardle, John, Washington, Jasmin E., Weintroub, Jonathan, Wharton, Robert, Wiik, Kaj, Witzel, Gunther, Wondrak, Michael F., Wong, George N., Wu, Qingwen, Yadlapalli, Nitika, Yamaguchi, Paul, Yfantis, Aristomenis, Yoon, Doosoo, Young, André, Young, Ken, Younsi, Ziri, Yu, Wei, Yuan, Feng, Yuan, Ye-Fei, Zensus, J. Anton, Zhang, Shuo, Zhao, Guang-Yao, and Zhao, Shan-Shan

Abstract

The Event Horizon Telescope (EHT) is a millimeter very long baseline interferometry (VLBI) array that has imaged the apparent shadows of the supermassive black holes M87* and Sagittarius A*. Polarimetric data from these observations contain a wealth of information on the black hole and accretion flow properties. In this work, we develop polarimetric geometric modeling methods for mm-VLBI data, focusing on approaches that fit data products with differing degrees of invariance to broad classes of calibration errors. We establish a fitting procedure using a polarimetric “m-ring” model to approximate the image structure near a black hole. By fitting this model to synthetic EHT data from general relativistic magnetohydrodynamic models, we show that the linear and circular polarization structure can be successfully approximated with relatively few model parameters. We then fit this model to EHT observations of M87* taken in 2017. In total intensity and linear polarization, the m-ring fits are consistent with previous results from imaging methods. In circular polarization, the m-ring fits indicate the presence of event-horizon-scale circular polarization structure, with a persistent dipolar asymmetry and orientation across several days. The same structure was recovered independently of observing band, used data products, and model assumptions. Despite this broad agreement, imaging methods do not produce similarly consistent results. Our circular polarization results, which imposed additional assumptions on the source structure, should thus be interpreted with some caution. Polarimetric geometric modeling provides a useful and powerful method to constrain the properties of horizon-scale polarized emission, particularly for sparse arrays like the EHT.

Published
2023

43. Inconsistent, downplayed, and pathologized: How mining's gendered impacts are considered in BC environmental assessment.

Author

Dempsey, Jessica, Doebeli, Anna Gabriela, Hoogeveen, Dawn, Quinn, Ceall, and Sosa‐Aranda, Inari

Subjects
*NONBINARY people, *INDIGENOUS women, *LGBTQ+ people, *INDIGENOUS children, *ENVIRONMENTAL impact analysis, *OFFICES
Abstract

To what extent do mining environmental assessments in British Columbia (BC) consider gendered impacts? How are they considered? And how are these considerations shaped during the environmental assessment process? To answer these questions we undertook a systematic review of all completed BC mining environmental assessments between 1995 and 2019 (n = 37). Through a careful reading of documentation archived in the BC Environmental Assessment Office registry, we found that 60% of projects did not consider the gendered impacts of mining development; the remaining 40% of projects inconsistently assessed gendered impacts. While noting an increase in gender considerations in environmental assessments since 1995, also quantified in our results is what has not changed. Even where gender is considered, the assessments often collapse this concern into one of "women's issues," obscuring intersectional impacts and downplaying violence along racialized and gender diverse lines, including those experienced by Indigenous women, children, two‐spirit, trans, queer and non‐binary people. Environmental assessment is a regulatory tool designed to adjudicate the impacts of mining projects, yet our results lead us to conclude that it is also a tool of environmental injustice, compounding and further sedimenting heteropatriarchal and racialized patterns produced through generations of settler colonial resource extraction in BC. Key Messages: Between 1995 and 2019, 60% of all British Columbia mining environmental assessments did not consider gendered impacts.The remaining 40% inconsistently and weakly considered gendered impacts, obscuring intersectional impacts and downplaying violence.Mining environmental assessments also tend to pathologize communities and downplay concerns raised by communities and public health. [ABSTRACT FROM AUTHOR]

Published
2023
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46. Comparison of Polarized Radiative Transfer Codes Used by the EHT Collaboration

Author

Prather, Ben, Dexter, Jason, Mościbrodzka, M., Pu, Hung-Yi, Bronzwaer, Thomas, Davelaar, Jordy, Younsi, Ziri, Gammie, Charles F., Gold, R., Wong, George N., Akiyama, Kazunori, Alberdi, Antxon, Alef, Walter, Algaba, Juan-Carlos, Anantua, Richard, Asada, K., Azulay, R., Bach, U., Baczko, A. K., Ball, David, Baloković, Mislav, Barrett, John, Bauböck, M., Benson, Bradford A., Bintley, Dan, Blackburn, Lindy, Blundell, Raymond, Bouman, K. L., Bower, G. C., Boyce, Hope, Bremer, M., Brinkerink, C. D., Brissenden, Roger, Britzen, Silke, Broderick, Avery E., Broguière, D., Bustamente, Sandra, Byun, Do Young, Carlstrom, J. E., Ceccobello, Chiara, Chael, A., Chan, Chi Kwan, Chang, Dominic O., Chatterjee, Koushik, Chatterjee, S., Chen, Ming Tang, Chen, Yongjun, Cheng, X. P., Cho, I., Christian, Pierre, Conroy, Nicholas S., Conway, John, Cordes, James M., Crawford, Thomas M., Crew, G., Cruz-Osorio, Alejandro, Cui, Yuzhu, De Laurentis, Mariafelicia, Deane, R. P., Dempsey, Jessica, Desvignes, Gregory, Dhruv, Vedant, Doeleman, S., Dougal, Sean, Dzib, Sergio A., Eatough, Ralph P., Emami, Razieh, Falcke, H.D., Farah, Joseph R., Fish, V., Fomalont, E., Ford, H. Alyson, Fraga-Encinas, R., Freeman, William T., Friberg, P., Fromm, Christian M., Fuentes, Antonio, Galison, Peter, Garcia, Roberto, Gentaz, Olivier, Georgiev, Boris, Goddi, C., Gómez-Ruiz, Arturo I., Gomez, J. L., Gu, Minfeng, Gurwell, M., Hada, K., Haggard, Daryl, Haworth, Kari, Hecht, Michael H., Hesper, R., Heumann, Dirk, Ho, Luis C., Ho, Paul, Honma, Mareki, Huang, Chih Wei L., Huang, Lei, Hughes, D., Ikeda, Shiro, and Impellizzeri, C. M. V.

Subjects
Astronomy, Astrophysics and Cosmology
Abstract

Interpretation of resolved polarized images of black holes by the Event Horizon Telescope (EHT) requires predictions of the polarized emission observable by an Earth-based instrument for a particular model of the black hole accretion system. Such predictions are generated by general relativistic radiative transfer (GRRT) codes, which integrate the equations of polarized radiative transfer in curved spacetime. A selection of ray-tracing GRRT codes used within the EHT Collaboration is evaluated for accuracy and consistency in producing a selection of test images, demonstrating that the various methods and implementations of radiative transfer calculations are highly consistent. When imaging an analytic accretion model, we find that all codes produce images similar within a pixel-wise normalized mean squared error (NMSE) of 0.012 in the worst case. When imaging a snapshot from a cell-based magnetohydrodynamic simulation, we find all test images to be similar within NMSEs of 0.02, 0.04, 0.04, and 0.12 in Stokes I, Q, U, and V, respectively. We additionally find the values of several image metrics relevant to published EHT results to be in agreement to much better precision than measurement uncertainties.

Published
2023

48. The repair work and future plan for the Auto-Correlation Spectral Imaging System (ACSIS) at the James Clerk Maxwell Telescope (JCMT)

Author

Liu, Kuan-Yu, primary, Bintley, Daniel, additional, Berthold, Ryan, additional, Bell, Graham S., additional, Wang, Ming-Jye, additional, Chen, Ming-Tang, additional, Huang, Yau De, additional, Han, Chih-Chiang, additional, Chiong, Chau-Ching, additional, Li, Chao-Te, additional, Jiang, Homin, additional, Kubo, Derek, additional, Fuller, Gary A., additional, Zhong, Weiye, additional, Liu, Junhao, additional, Parsons, Harriet, additional, Dempsey, Jessica, additional, Friberg, Per, additional, Purves, Maren, additional, Graves, Sarah F., additional, Cookson, Jamie L., additional, Sison, Ed, additional, Jiang, Xue-Jian, additional, Mizuno, Izumi, additional, Li, Shaoliang, additional, Stahm, William G., additional, Walther, Craig A., additional, Yu, Wei, additional, and Duan, Ran, additional

Published
2022
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50. Resolving the Inner Parsec of the Blazar J1924–2914 with the Event Horizon Telescope

Author

Issaoun, Sara, primary, Wielgus, Maciek, additional, Jorstad, Svetlana, additional, Krichbaum, Thomas P., additional, Blackburn, Lindy, additional, Janssen, Michael, additional, Chan, Chi-kwan, additional, Pesce, Dominic W., additional, Gómez, José L., additional, Akiyama, Kazunori, additional, Mościbrodzka, Monika, additional, Martí-Vidal, Iván, additional, Chael, Andrew, additional, Lico, Rocco, additional, Liu, Jun, additional, Ramakrishnan, Venkatessh, additional, Lisakov, Mikhail, additional, Fuentes, Antonio, additional, Zhao, Guang-Yao, additional, Moriyama, Kotaro, additional, Broderick, Avery E., additional, Tiede, Paul, additional, MacDonald, Nicholas R., additional, Mizuno, Yosuke, additional, Traianou, Efthalia, additional, Loinard, Laurent, additional, Davelaar, Jordy, additional, Gurwell, Mark, additional, Lu, Ru-Sen, additional, Alberdi, Antxon, additional, Alef, Walter, additional, Algaba, Juan Carlos, additional, Anantua, Richard, additional, Asada, Keiichi, additional, Azulay, Rebecca, additional, Bach, Uwe, additional, Baczko, Anne-Kathrin, additional, Ball, David, additional, Baloković, Mislav, additional, Barrett, John, additional, Bauböck, Michi, additional, Benson, Bradford A., additional, Bintley, Dan, additional, Blundell, Raymond, additional, Boland, Wilfred, additional, Bouman, Katherine L., additional, Bower, Geoffrey C., additional, Boyce, Hope, additional, Bremer, Michael, additional, Brinkerink, Christiaan D., additional, Brissenden, Roger, additional, Britzen, Silke, additional, Broguiere, Dominique, additional, Bronzwaer, Thomas, additional, Bustamante, Sandra, additional, Byun, Do-Young, additional, Carlstrom, John E., additional, Ceccobello, Chiara, additional, Chatterjee, Koushik, additional, Chatterjee, Shami, additional, Chen, Ming-Tang, additional, Chen, Yongjun, additional, Cho, Ilje, additional, Christian, Pierre, additional, Conroy, Nicholas S., additional, Conway, John E., additional, Cordes, James M., additional, Crawford, Thomas M., additional, Crew, Geoffrey B., additional, Cruz-Osorio, Alejandro, additional, Cui, Yuzhu, additional, Laurentis, Mariafelicia De, additional, Deane, Roger, additional, Dempsey, Jessica, additional, Desvignes, Gregory, additional, Dexter, Jason, additional, Doeleman, Sheperd S., additional, Dhruv, Vedant, additional, Dzib Quijano, Sergio Abraham, additional, Eatough, Ralph P., additional, Emami, Razieh, additional, Falcke, Heino, additional, Farah, Joseph, additional, Fish, Vincent L., additional, Fomalont, Ed, additional, Ford, H. Alyson, additional, Fraga-Encinas, Raquel, additional, Freeman, William T., additional, Friberg, Per, additional, Fromm, Christian M., additional, Galison, Peter, additional, Gammie, Charles F., additional, García, Roberto, additional, Gentaz, Olivier, additional, Georgiev, Boris, additional, Goddi, Ciriaco, additional, Gold, Roman, additional, Gómez-Ruiz, Arturo I., additional, Gu, Minfeng, additional, Hada, Kazuhiro, additional, Haggard, Daryl, additional, Hecht, Michael H., additional, Hesper, Ronald, additional, Ho, Luis C., additional, Ho, Paul, additional, Honma, Mareki, additional, Huang, Chih-Wei L., additional, Huang, Lei, additional, Hughes, David H., additional, Ikeda, Shiro, additional, Impellizzeri, C. M. Violette, additional, Inoue, Makoto, additional, James, David J., additional, Jannuzi, Buell T., additional, Jeter, Britton, additional, Jiang, Wu, additional, Jimenez-Rosales, Alejandra, additional, Johnson, Michael D., additional, Joshi, Abhishek V., additional, Jung, Taehyun, additional, Karami, Mansour, additional, Karuppusamy, Ramesh, additional, Kawashima, Tomohisa, additional, Keating, Garrett K., additional, Kettenis, Mark, additional, Kim, Dong-Jin, additional, Kim, Jae-Young, additional, Kim, Jongsoo, additional, Kim, Junhan, additional, Kino, Motoki, additional, Koay, Jun Yi, additional, Kocherlakota, Prashant, additional, Kofuji, Yutaro, additional, Koch, Patrick M., additional, Koyama, Shoko, additional, Kramer, Carsten, additional, Kramer, Michael, additional, Kuo, Cheng-Yu, additional, Bella, Noemi La, additional, Lauer, Tod R., additional, Lee, Daeyoung, additional, Lee, Sang-Sung, additional, Leung, Po Kin, additional, Levis, Aviad, additional, Li, Zhiyuan, additional, Lindahl, Greg, additional, Lindqvist, Michael, additional, Liu, Kuo, additional, Liuzzo, Elisabetta, additional, Lo, Wen-Ping, additional, Lobanov, Andrei P., additional, Lonsdale, Colin, additional, Mao, Jirong, additional, Marchili, Nicola, additional, Markoff, Sera, additional, Marrone, Daniel P., additional, Marscher, Alan P., additional, Matsushita, Satoki, additional, Matthews, Lynn D., additional, Medeiros, Lia, additional, Menten, Karl M., additional, Michalik, Daniel, additional, Mizuno, Izumi, additional, Moran, James M., additional, Müller, Cornelia, additional, Mus, Alejandro, additional, Musoke, Gibwa, additional, Myserlis, Ioannis, additional, Nadolski, Andrew, additional, Nagai, Hiroshi, additional, Nagar, Neil M., additional, Nakamura, Masanori, additional, Narayan, Ramesh, additional, Narayanan, Gopal, additional, Natarajan, Iniyan, additional, Nathanail, Antonios, additional, Neilsen, Joey, additional, Neri, Roberto, additional, Ni, Chunchong, additional, Noutsos, Aristeidis, additional, Nowak, Michael A., additional, Oh, Junghwan, additional, Okino, Hiroki, additional, Olivares, Héctor, additional, Ortiz-León, Gisela N., additional, Oyama, Tomoaki, additional, Özel, Feryal, additional, Palumbo, Daniel C. M., additional, Paraschos, Georgios Filippos, additional, Park, Jongho, additional, Parsons, Harriet, additional, Patel, Nimesh, additional, Pen, Ue-Li, additional, Piétu, Vincent, additional, Plambeck, Richard, additional, PopStefanija, Aleksandar, additional, Porth, Oliver, additional, Pötzl, Felix M., additional, Prather, Ben, additional, Preciado-López, Jorge A., additional, Psaltis, Dimitrios, additional, Pu, Hung-Yi, additional, Rao, Ramprasad, additional, Rawlings, Mark G., additional, Raymond, Alexander W., additional, Rezzolla, Luciano, additional, Ricarte, Angelo, additional, Ripperda, Bart, additional, Roelofs, Freek, additional, Rogers, Alan, additional, Ros, Eduardo, additional, Romero-Canizales, Cristina, additional, Roshanineshat, Arash, additional, Rottmann, Helge, additional, Roy, Alan L., additional, Ruiz, Ignacio, additional, Ruszczyk, Chet, additional, Rygl, Kazi L. J., additional, Sánchez, Salvador, additional, Sánchez-Arguelles, David, additional, Sanchez-Portal, Miguel, additional, Sasada, Mahito, additional, Satapathy, Kaushik, additional, Savolainen, Tuomas, additional, Schloerb, F. Peter, additional, Schuster, Karl-Friedrich, additional, Shao, Lijing, additional, Shen, Zhiqiang, additional, Small, Des, additional, Sohn, Bong Won, additional, SooHoo, Jason, additional, Souccar, Kamal, additional, Sun, He, additional, Tazaki, Fumie, additional, Tetarenko, Alexandra J., additional, Tilanus, Remo P. J., additional, Titus, Michael, additional, Torne, Pablo, additional, Trent, Tyler, additional, Trippe, Sascha, additional, van Bemmel, Ilse, additional, van Langevelde, Huib Jan, additional, van Rossum, Daniel R., additional, Vos, Jesse, additional, Wagner, Jan, additional, Ward-Thompson, Derek, additional, Wardle, John, additional, Weintroub, Jonathan, additional, Wex, Norbert, additional, Wharton, Robert, additional, Wiik, Kaj, additional, Witzel, Gunther, additional, Wondrak, Michael, additional, Wong, George N., additional, Wu, Qingwen, additional, Yamaguchi, Paul, additional, Yoon, Doosoo, additional, Young, André, additional, Young, Ken, additional, Younsi, Ziri, additional, Yuan, Feng, additional, Yuan, Ye-Fei, additional, Zensus, J. Anton, additional, Zhang, Shuo, additional, and Zhao, Shan-Shan, additional

Published
2022
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