학술논문

Resolved Magnetic-Field Structure and Variability Near the Event Horizon of Sagittarius A*
Document Type
Working Paper
Source
Subject
Astrophysics - High Energy Astrophysical Phenomena
Astrophysics - Astrophysics of Galaxies
Astrophysics - Instrumentation and Methods for Astrophysics
Language
Abstract
Near a black hole, differential rotation of a magnetized accretion disk is thought to produce an instability that amplifies weak magnetic fields, driving accretion and outflow. These magnetic fields would naturally give rise to the observed synchrotron emission in galaxy cores and to the formation of relativistic jets, but no observations to date have been able to resolve the expected horizon-scale magnetic-field structure. We report interferometric observations at 1.3-millimeter wavelength that spatially resolve the linearly polarized emission from the Galactic Center supermassive black hole, Sagittarius A*. We have found evidence for partially ordered fields near the event horizon, on scales of ~6 Schwarzschild radii, and we have detected and localized the intra-hour variability associated with these fields.
Comment: Accepted for publication in Science; includes Supplementary material