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arXiv · 2501.08685

The putative center in NGC 1052

Anne-Kathrin Baczko·Matthias Kadler·Eduardo Ros·Christian M. Fromm·Maciek Wielgus·Manel Perucho·Thomas P. Krichbaum·Mislav Baloković·Lindy Blackburn·Chi-kwan Chan·Sara Issaoun·Michael Janssen·Luca Ricci·Kazunori Akiyama·Ezequiel Albentosa-Ruíz·Antxon Alberdi·Walter Alef·Juan Carlos Algaba·Richard Anantua·Keiichi Asada·Rebecca Azulay·Uwe Bach·David Ball·Bidisha Bandyopadhyay·John Barrett·Michi Bauböck·Bradford A. Benson·Dan Bintley·Raymond Blundell·Katherine L. Bouman·Geoffrey C. Bower·Hope Boyce·Michael Bremer·Christiaan D. Brinkerink·Roger Brissenden·Silke Britzen·Avery E. Broderick·Dominique Broguiere·Thomas Bronzwaer·Sandra Bustamante·Do-Young Byun·John E. Carlstrom·Chiara Ceccobello·Andrew Chael·Dominic O. Chang·Koushik Chatterjee·Shami Chatterjee·Ming-Tang Chen·Yongjun Chen·Xiaopeng Cheng·Ilje Cho·Pierre Christian·Nicholas S. Conroy·John E. Conway·James M. Cordes·Thomas M. Crawford·Geoffrey B. Crew·Alejandro Cruz-Osorio·Yuzhu Cui·Rohan Dahale·Jordy Davelaar·Mariafelicia De Laurentis·Roger Deane·Jessica Dempsey·Gregory Desvignes·Jason Dexter·Vedant Dhruv·Indu K. Dihingia·Sheperd S. Doeleman·Sean Taylor Dougall·Sergio A. Dzib·Ralph P. Eatough·Razieh Emami·Heino Falcke·Joseph Farah·Vincent L. Fish·Edward Fomalont·H. Alyson Ford·Marianna Foschi·Raquel Fraga-Encinas·William T. Freeman·Per Friberg·Antonio Fuentes·Peter Galison·Charles F. Gammie·Roberto García·Olivier Gentaz·Boris Georgiev·Ciriaco Goddi·Roman Gold·Arturo I. Gómez-Ruiz·José L. Gómez·Minfeng Gu·Mark Gurwell·Kazuhiro Hada·Daryl Haggard·Kari Haworth·Michael H. Hecht·Ronald Hesper·Dirk Heumann

Abstract

Many active galaxies harbor powerful relativistic jets, however, the detailed mechanisms of their formation and acceleration remain poorly understood. To investigate the area of jet acceleration and collimation with the highest available angular resolution, we study the innermost region of the bipolar jet in the nearby low-ionization nuclear emission-line region (LINER) galaxy NGC 1052. We combined observations of NGC 1052 taken with VLBA, GMVA, and EHT over one week in the spring of 2017. For the first time, NGC 1052 was detected with the EHT, providing a size of the central region in-between both jet bases of 250 RS (Schwarzschild radii) perpendicular to the jet axes. This size estimate supports previous studies of the jets expansion profile which suggest two breaks of the profile at around 300 RS and 10000 RS distances to the core. Furthermore, we estimated the magnetic field to be 1.25 Gauss at a distance of 22 {\mu}as from the central engine by fitting a synchrotron-self absorption spectrum to the innermost emission feature, which shows a spectral turn-over at about 130 GHz. Assuming a purely poloidal magnetic field, this implies an upper limit on the magnetic field strength at the event horizon of 26000 Gauss, which is consistent with previous measurements. The complex, low-brightness, double-sided jet structure in NGC 1052 makes it a challenge to detect the source at millimeter (mm) wavelengths. However, our first EHT observations have demonstrated that detection is possible up to at least 230 GHz. This study offers a glimpse through the dense surrounding torus and into the innermost central region, where the jets are formed. This has enabled us to finally resolve this region and provide improved constraints on its expansion and magnetic field strength.

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Anne-Kathrin Baczko, Matthias Kadler, Eduardo Ros, Christian M. Fromm, Maciek Wielgus, Manel Perucho, Thomas P. Krichbaum, Mislav Baloković, Lindy Blackburn, Chi-kwan Chan, Sara Issaoun, Michael Janssen, Luca Ricci, Kazunori Akiyama, Ezequiel Albentosa-Ruíz, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Uwe Bach, David Ball, Bidisha Bandyopadhyay, John Barrett, Michi Bauböck, Bradford A. Benson, Dan Bintley, Raymond Blundell, Katherine L. Bouman, Geoffrey C. Bower, Hope Boyce, Michael Bremer, Christiaan D. Brinkerink, Roger Brissenden, Silke Britzen, Avery E. Broderick, Dominique Broguiere, Thomas Bronzwaer, Sandra Bustamante, Do-Young Byun, John E. Carlstrom, Chiara Ceccobello, Andrew Chael, Dominic O. Chang, Koushik Chatterjee, Shami Chatterjee, Ming-Tang Chen, Yongjun Chen, Xiaopeng Cheng, Ilje Cho, Pierre Christian, Nicholas S. Conroy, John E. Conway, James M. Cordes, Thomas M. Crawford, Geoffrey B. Crew, Alejandro Cruz-Osorio, Yuzhu Cui, Rohan Dahale, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jessica Dempsey, Gregory Desvignes, Jason Dexter, Vedant Dhruv, Indu K. Dihingia, Sheperd S. Doeleman, Sean Taylor Dougall, Sergio A. Dzib, Ralph P. Eatough, Razieh Emami, Heino Falcke, Joseph Farah, Vincent L. Fish, Edward Fomalont, H. Alyson Ford, Marianna Foschi, Raquel Fraga-Encinas, William T. Freeman, Per Friberg, Antonio Fuentes, Peter Galison, Charles F. Gammie, Roberto García, Olivier Gentaz, Boris Georgiev, Ciriaco Goddi, Roman Gold, Arturo I. Gómez-Ruiz, José L. Gómez, Minfeng Gu, Mark Gurwell, Kazuhiro Hada, Daryl Haggard, Kari Haworth, Michael H. Hecht, Ronald Hesper, Dirk Heumann. 2025-01-15. The putative center in NGC 1052. https://doi.org/10.1051/0004-6361/202450898

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