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Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations

Fuente: arXiv

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Dettagli Bibliografici
Autori principali:	Saurabh, Müller, Hendrik, von Fellenberg, Sebastiano D., Tiede, Paul, Janssen, Michael, Blackburn, Lindy, Broderick, Avery E., Chavez, Erandi, Georgiev, Boris, Krichbaum, Thomas P., Moriyama, Kotaro, Nair, Dhanya G., Natarajan, Iniyan, Park, Jongho, West, Andrew Thomas, Wielgus, Maciek, Akiyama, Kazunori, Albentosa-Ruíz, Ezequiel, Alberdi, Antxon, Alef, Walter, Algaba, Juan Carlos, Anantua, Richard, Asada, Keiichi, 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., Bower, Geoffrey C., Bremer, Michael, Brissenden, Roger, Britzen, Silke, Broguiere, Dominique, Bronzwaer, Thomas, Bustamante, Sandra, Carlos, Douglas F., Carlstrom, John E., Chael, Andrew, Chan, Chi-kwan, Chang, Dominic O., Chatterjee, Koushik, Chatterjee, Shami, Chen, Ming-Tang, Chen, Yongjun, Cheng, Xiaopeng, Chichura, Paul, Cho, Ilje, Christian, Pierre, Conroy, Nicholas S., Conway, John E., Crawford, Thomas M., Crew, Geoffrey B., Cruz-Osorio, Alejandro, Cui, Yuzhu, Curd, Brandon, Dahale, Rohan, Davelaar, Jordy, De Laurentis, Mariafelicia, Deane, Roger, Desvignes, Gregory, Dexter, Jason, Dhruv, Vedant, Dihingia, Indu K., Doeleman, Sheperd S., Dzib, Sergio A., Eatough, Ralph P., Emami, Razieh, Falcke, Heino, Farah, Joseph, Fish, Vincent L., Fomalont, Edward, 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, Goddi, Ciriaco, 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, 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, Kuo, Cheng-Yu, La Bella, Noemi, Lee, Deokhyeong, Lee, Sang-Sung, Levis, Aviad, Li, Shaoliang, 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., Messias, Hugo, Mizuno, Izumi, Mizuno, Yosuke, Montgomery, Joshua, Moran, James M., Moscibrodzka, Monika, Mulaudzi, Wanga, Müller, Cornelia, Mus, Alejandro, Musoke, Gibwa, Myserlis, Ioannis, Nagai, Hiroshi, Nagar, Neil M., Nakamura, Masanori, Narayanan, Gopal, 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, Parsons, Harriet, Patel, Nimesh, Pen, Ue-Li, Pesce, Dominic W., Piétu, Vincent, Plavin, Alexander, PopStefanija, Aleksandar, Porth, Oliver, Prather, Ben, Principe, Giacomo, Psaltis, Dimitrios, Pu, Hung-Yi, Rahlin, Alexandra, Ramakrishnan, Venkatessh, Rao, Ramprasad, Rawlings, Mark G., Rezzolla, Luciano, Ricarte, Angelo, Ricci, Luca, Ripperda, Bart, Röder, Jan, Roelofs, Freek, Romero-Cañizales, Cristina, Ros, Eduardo, Roshanineshat, Arash, Rottmann, Helge, Roy, Alan L., Ruiz, Ignacio, Ruszczyk, Chet, Rygl, Kazi L. J., Salas, León D. S., 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, Silpa, Sasikumar, Small, Des, Smith, Randall, Sohn, Bong Won, SooHoo, Jason, Souccar, Kamal, Stanway, Joshua S., Sun, He, Tazaki, Fumie, Tetarenko, Alexandra J., Tilanus, Remo P. J., Titus, Michael, Toma, Kenji, 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., Wongphexhauxsorn, Jompoj, Wu, Qingwen, Yadlapalli, Nitika, Yamaguchi, Paul, Yfantis, Aristomenis, Yoon, Doosoo, Young, André, Younsi, Ziri, Yu, Wei, Yuan, Feng, Yuan, Ye-Fei, Zeng, Ai-Ling, Zensus, J. Anton, Zhang, Shuo, Zhao, Guang-Yao, Zhao, Shan-Shan
Natura:	Preprint
Pubblicazione:	2025
Soggetti:	High Energy Astrophysical Phenomena
Accesso online:	Acceder al recurso
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_version_	1866910002867863552
author	Saurabh Müller, Hendrik von Fellenberg, Sebastiano D. Tiede, Paul Janssen, Michael Blackburn, Lindy Broderick, Avery E. Chavez, Erandi Georgiev, Boris Krichbaum, Thomas P. Moriyama, Kotaro Nair, Dhanya G. Natarajan, Iniyan Park, Jongho West, Andrew Thomas Wielgus, Maciek Akiyama, Kazunori Albentosa-Ruíz, Ezequiel Alberdi, Antxon Alef, Walter Algaba, Juan Carlos Anantua, Richard Asada, Keiichi 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. Bower, Geoffrey C. Bremer, Michael Brissenden, Roger Britzen, Silke Broguiere, Dominique Bronzwaer, Thomas Bustamante, Sandra Carlos, Douglas F. Carlstrom, John E. Chael, Andrew Chan, Chi-kwan Chang, Dominic O. Chatterjee, Koushik Chatterjee, Shami Chen, Ming-Tang Chen, Yongjun Cheng, Xiaopeng Chichura, Paul Cho, Ilje Christian, Pierre Conroy, Nicholas S. Conway, John E. Crawford, Thomas M. Crew, Geoffrey B. Cruz-Osorio, Alejandro Cui, Yuzhu Curd, Brandon Dahale, Rohan Davelaar, Jordy De Laurentis, Mariafelicia Deane, Roger Desvignes, Gregory Dexter, Jason Dhruv, Vedant Dihingia, Indu K. Doeleman, Sheperd S. Dzib, Sergio A. Eatough, Ralph P. Emami, Razieh Falcke, Heino Farah, Joseph Fish, Vincent L. Fomalont, Edward 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 Goddi, Ciriaco 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 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 Kuo, Cheng-Yu La Bella, Noemi Lee, Deokhyeong Lee, Sang-Sung Levis, Aviad Li, Shaoliang 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. Messias, Hugo Mizuno, Izumi Mizuno, Yosuke Montgomery, Joshua Moran, James M. Moscibrodzka, Monika Mulaudzi, Wanga Müller, Cornelia Mus, Alejandro Musoke, Gibwa Myserlis, Ioannis Nagai, Hiroshi Nagar, Neil M. Nakamura, Masanori Narayanan, Gopal 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 Parsons, Harriet Patel, Nimesh Pen, Ue-Li Pesce, Dominic W. Piétu, Vincent Plavin, Alexander PopStefanija, Aleksandar Porth, Oliver Prather, Ben Principe, Giacomo Psaltis, Dimitrios Pu, Hung-Yi Rahlin, Alexandra Ramakrishnan, Venkatessh Rao, Ramprasad Rawlings, Mark G. Rezzolla, Luciano Ricarte, Angelo Ricci, Luca Ripperda, Bart Röder, Jan Roelofs, Freek Romero-Cañizales, Cristina Ros, Eduardo Roshanineshat, Arash Rottmann, Helge Roy, Alan L. Ruiz, Ignacio Ruszczyk, Chet Rygl, Kazi L. J. Salas, León D. S. 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 Silpa, Sasikumar Small, Des Smith, Randall Sohn, Bong Won SooHoo, Jason Souccar, Kamal Stanway, Joshua S. Sun, He Tazaki, Fumie Tetarenko, Alexandra J. Tilanus, Remo P. J. Titus, Michael Toma, Kenji 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. Wongphexhauxsorn, Jompoj Wu, Qingwen Yadlapalli, Nitika Yamaguchi, Paul Yfantis, Aristomenis Yoon, Doosoo Young, André Younsi, Ziri Yu, Wei Yuan, Feng Yuan, Ye-Fei Zeng, Ai-Ling Zensus, J. Anton Zhang, Shuo Zhao, Guang-Yao Zhao, Shan-Shan
author_facet	Saurabh Müller, Hendrik von Fellenberg, Sebastiano D. Tiede, Paul Janssen, Michael Blackburn, Lindy Broderick, Avery E. Chavez, Erandi Georgiev, Boris Krichbaum, Thomas P. Moriyama, Kotaro Nair, Dhanya G. Natarajan, Iniyan Park, Jongho West, Andrew Thomas Wielgus, Maciek Akiyama, Kazunori Albentosa-Ruíz, Ezequiel Alberdi, Antxon Alef, Walter Algaba, Juan Carlos Anantua, Richard Asada, Keiichi 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. Bower, Geoffrey C. Bremer, Michael Brissenden, Roger Britzen, Silke Broguiere, Dominique Bronzwaer, Thomas Bustamante, Sandra Carlos, Douglas F. Carlstrom, John E. Chael, Andrew Chan, Chi-kwan Chang, Dominic O. Chatterjee, Koushik Chatterjee, Shami Chen, Ming-Tang Chen, Yongjun Cheng, Xiaopeng Chichura, Paul Cho, Ilje Christian, Pierre Conroy, Nicholas S. Conway, John E. Crawford, Thomas M. Crew, Geoffrey B. Cruz-Osorio, Alejandro Cui, Yuzhu Curd, Brandon Dahale, Rohan Davelaar, Jordy De Laurentis, Mariafelicia Deane, Roger Desvignes, Gregory Dexter, Jason Dhruv, Vedant Dihingia, Indu K. Doeleman, Sheperd S. Dzib, Sergio A. Eatough, Ralph P. Emami, Razieh Falcke, Heino Farah, Joseph Fish, Vincent L. Fomalont, Edward 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 Goddi, Ciriaco 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 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 Kuo, Cheng-Yu La Bella, Noemi Lee, Deokhyeong Lee, Sang-Sung Levis, Aviad Li, Shaoliang 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. Messias, Hugo Mizuno, Izumi Mizuno, Yosuke Montgomery, Joshua Moran, James M. Moscibrodzka, Monika Mulaudzi, Wanga Müller, Cornelia Mus, Alejandro Musoke, Gibwa Myserlis, Ioannis Nagai, Hiroshi Nagar, Neil M. Nakamura, Masanori Narayanan, Gopal 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 Parsons, Harriet Patel, Nimesh Pen, Ue-Li Pesce, Dominic W. Piétu, Vincent Plavin, Alexander PopStefanija, Aleksandar Porth, Oliver Prather, Ben Principe, Giacomo Psaltis, Dimitrios Pu, Hung-Yi Rahlin, Alexandra Ramakrishnan, Venkatessh Rao, Ramprasad Rawlings, Mark G. Rezzolla, Luciano Ricarte, Angelo Ricci, Luca Ripperda, Bart Röder, Jan Roelofs, Freek Romero-Cañizales, Cristina Ros, Eduardo Roshanineshat, Arash Rottmann, Helge Roy, Alan L. Ruiz, Ignacio Ruszczyk, Chet Rygl, Kazi L. J. Salas, León D. S. 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 Silpa, Sasikumar Small, Des Smith, Randall Sohn, Bong Won SooHoo, Jason Souccar, Kamal Stanway, Joshua S. Sun, He Tazaki, Fumie Tetarenko, Alexandra J. Tilanus, Remo P. J. Titus, Michael Toma, Kenji 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. Wongphexhauxsorn, Jompoj Wu, Qingwen Yadlapalli, Nitika Yamaguchi, Paul Yfantis, Aristomenis Yoon, Doosoo Young, André Younsi, Ziri Yu, Wei Yuan, Feng Yuan, Ye-Fei Zeng, Ai-Ling Zensus, J. Anton Zhang, Shuo Zhao, Guang-Yao Zhao, Shan-Shan
contents	We investigate the presence and spatial characteristics of the jet base emission in M87* at 230 GHz, enabled by the enhanced uv coverage in the 2021 Event Horizon Telescope (EHT) observations. The addition of the 12-m Kitt Peak Telescope and NOEMA provides two key intermediate-length baselines to SMT and the IRAM 30-m, giving sensitivity to emission structures at scales of $\sim250~μ$as and $\sim2500~μ$as (0.02 pc and 0.2 pc). Without these baselines, earlier EHT observations lacked the capability to constrain emission on large scales, where a "missing flux" of order $\sim1$ Jy is expected. To probe these scales, we analyzed closure phases, robust against station-based gain errors, and modeled the jet base emission using a simple Gaussian offset from the compact ring emission at separations $>100~μ$as. Our analysis reveals a Gaussian feature centered at ($Δ$RA $\approx320~μ$as, $Δ$Dec $\approx60~μ$as), a projected separation of $\approx5500$ AU, with a flux density of only $\sim60$ mJy, implying that most of the missing flux in previous studies must arise from larger scales. Brighter emission at these scales is ruled out, and the data do not favor more complex models. This component aligns with the inferred direction of the large-scale jet and is consistent with emission from the jet base. While our findings indicate detectable jet base emission at 230 GHz, coverage from only two intermediate baselines limits reconstruction of its morphology. We therefore treat the recovered Gaussian as an upper limit on the jet base flux density. Future EHT observations with expanded intermediate-baseline coverage will be essential to constrain the structure and nature of this component.
format	Preprint
id	arxiv_https___arxiv_org_abs_2512_08970
institution	arXiv
publishDate	2025
record_format	arxiv
spellingShingle	Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations Saurabh Müller, Hendrik von Fellenberg, Sebastiano D. Tiede, Paul Janssen, Michael Blackburn, Lindy Broderick, Avery E. Chavez, Erandi Georgiev, Boris Krichbaum, Thomas P. Moriyama, Kotaro Nair, Dhanya G. Natarajan, Iniyan Park, Jongho West, Andrew Thomas Wielgus, Maciek Akiyama, Kazunori Albentosa-Ruíz, Ezequiel Alberdi, Antxon Alef, Walter Algaba, Juan Carlos Anantua, Richard Asada, Keiichi 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. Bower, Geoffrey C. Bremer, Michael Brissenden, Roger Britzen, Silke Broguiere, Dominique Bronzwaer, Thomas Bustamante, Sandra Carlos, Douglas F. Carlstrom, John E. Chael, Andrew Chan, Chi-kwan Chang, Dominic O. Chatterjee, Koushik Chatterjee, Shami Chen, Ming-Tang Chen, Yongjun Cheng, Xiaopeng Chichura, Paul Cho, Ilje Christian, Pierre Conroy, Nicholas S. Conway, John E. Crawford, Thomas M. Crew, Geoffrey B. Cruz-Osorio, Alejandro Cui, Yuzhu Curd, Brandon Dahale, Rohan Davelaar, Jordy De Laurentis, Mariafelicia Deane, Roger Desvignes, Gregory Dexter, Jason Dhruv, Vedant Dihingia, Indu K. Doeleman, Sheperd S. Dzib, Sergio A. Eatough, Ralph P. Emami, Razieh Falcke, Heino Farah, Joseph Fish, Vincent L. Fomalont, Edward 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 Goddi, Ciriaco 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 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 Kuo, Cheng-Yu La Bella, Noemi Lee, Deokhyeong Lee, Sang-Sung Levis, Aviad Li, Shaoliang 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. Messias, Hugo Mizuno, Izumi Mizuno, Yosuke Montgomery, Joshua Moran, James M. Moscibrodzka, Monika Mulaudzi, Wanga Müller, Cornelia Mus, Alejandro Musoke, Gibwa Myserlis, Ioannis Nagai, Hiroshi Nagar, Neil M. Nakamura, Masanori Narayanan, Gopal 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 Parsons, Harriet Patel, Nimesh Pen, Ue-Li Pesce, Dominic W. Piétu, Vincent Plavin, Alexander PopStefanija, Aleksandar Porth, Oliver Prather, Ben Principe, Giacomo Psaltis, Dimitrios Pu, Hung-Yi Rahlin, Alexandra Ramakrishnan, Venkatessh Rao, Ramprasad Rawlings, Mark G. Rezzolla, Luciano Ricarte, Angelo Ricci, Luca Ripperda, Bart Röder, Jan Roelofs, Freek Romero-Cañizales, Cristina Ros, Eduardo Roshanineshat, Arash Rottmann, Helge Roy, Alan L. Ruiz, Ignacio Ruszczyk, Chet Rygl, Kazi L. J. Salas, León D. S. 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 Silpa, Sasikumar Small, Des Smith, Randall Sohn, Bong Won SooHoo, Jason Souccar, Kamal Stanway, Joshua S. Sun, He Tazaki, Fumie Tetarenko, Alexandra J. Tilanus, Remo P. J. Titus, Michael Toma, Kenji 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. Wongphexhauxsorn, Jompoj Wu, Qingwen Yadlapalli, Nitika Yamaguchi, Paul Yfantis, Aristomenis Yoon, Doosoo Young, André Younsi, Ziri Yu, Wei Yuan, Feng Yuan, Ye-Fei Zeng, Ai-Ling Zensus, J. Anton Zhang, Shuo Zhao, Guang-Yao Zhao, Shan-Shan High Energy Astrophysical Phenomena We investigate the presence and spatial characteristics of the jet base emission in M87* at 230 GHz, enabled by the enhanced uv coverage in the 2021 Event Horizon Telescope (EHT) observations. The addition of the 12-m Kitt Peak Telescope and NOEMA provides two key intermediate-length baselines to SMT and the IRAM 30-m, giving sensitivity to emission structures at scales of $\sim250~μ$as and $\sim2500~μ$as (0.02 pc and 0.2 pc). Without these baselines, earlier EHT observations lacked the capability to constrain emission on large scales, where a "missing flux" of order $\sim1$ Jy is expected. To probe these scales, we analyzed closure phases, robust against station-based gain errors, and modeled the jet base emission using a simple Gaussian offset from the compact ring emission at separations $>100~μ$as. Our analysis reveals a Gaussian feature centered at ($Δ$RA $\approx320~μ$as, $Δ$Dec $\approx60~μ$as), a projected separation of $\approx5500$ AU, with a flux density of only $\sim60$ mJy, implying that most of the missing flux in previous studies must arise from larger scales. Brighter emission at these scales is ruled out, and the data do not favor more complex models. This component aligns with the inferred direction of the large-scale jet and is consistent with emission from the jet base. While our findings indicate detectable jet base emission at 230 GHz, coverage from only two intermediate baselines limits reconstruction of its morphology. We therefore treat the recovered Gaussian as an upper limit on the jet base flux density. Future EHT observations with expanded intermediate-baseline coverage will be essential to constrain the structure and nature of this component.
title	Probing jet base emission of M87* with the 2021 Event Horizon Telescope observations
topic	High Energy Astrophysical Phenomena
url	https://arxiv.org/abs/2512.08970