VLBA22A-148
Probing the Jet Base of M87 in the Time Domain
Abstract
Recent Event Horizon Telescope observations of M87 have revealed a ring-like structure near the event horizon. The corresponding linear polarization images indicate that a strong, ordered, and poloidal-dominated magnetic field may exist in the vicinity of the black hole, in good agreement with the models of AGN jet launching. The ring emission may consist of two components: the gravitationally lensed photon ring and the photons not entirely bound by the gravity, such as the emission from the plasma in the forward jet. It is, unfortunately, not very straightforward to disentangle these components with the 1mm images only. Our recent GMVA+ALMA observations of M87 at 3mm indicate that a ring-like structure may exist in the core of M87 at 3mm as well. Investigating the images of the horizon-scale emission at 1 and 3mm would bring invaluable information on the origin of the ring and the physical properties of the innermost accretion flows and jet base. Here we propose new observations with a global VLBI array in two epochs near in time to the planned GMVA+ALMA observations in Spring 2022. Our observations will test the jet launching models and constrain the jet's acceleration mechanism, Faraday rotation, and magnetic field structure.
Investigators
| Name | Institution |
|---|---|
| GBT Operator | Green Bank Observatory |
| Keiichi Asada | Academia Sinica |
| Kazuhiro Hada | Istituto Nazionale di Astrofisica; National Astronomical Observatory of Japan |
| Masanori Nakamura | Academia Sinica; National Institute of Technology, Hachinohe College |
| Hung-Yi Pu | Perimeter Institute for Theoretical Physics |
| Rusen Lu | Max-Planck-Institut für Radioastronomie; Shanghai Astronomical Observatory, CAS |
| Fumie Tazaki | National Astronomical Observatory of Japan ; Tokyo Electron Technology Solutions Ltd. |
| Jongho Park * | Kyung Hee University |
| Andrei Lobanov | Max-Planck-Institut für Radioastronomie |
| Jae-Young Kim | Max-Planck-Institut für Radioastronomie; Kyungpook National University |
| Wu Jiang | Shanghai Astronomical Observatory, CAS |
| zhi-qiang shen | Shanghai Astronomical Observatory, CAS |
| Tomohisa Kawashima | Tokyo, University of |
| Feng Yuan | Shanghai Astronomical Observatory, CAS |
| Thomas Krichbaum | Max-Planck-Institut für Radioastronomie |
* indicates the PI