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arXiv · 1310.0146

Evidence for A Parsec-scale Jet from The Galactic Center Black Hole: Interaction with Local Gas

Zhiyuan Li·Mark R. Morris·Frederick K. Baganoff
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Abstract

Despite strong physical reasons that they should exist and decades of search, jets from the Galactic Center Black Hole, Sgr A*, have not yet been convincingly detected. Based on high-resolution Very Large Array images and ultra-deep imaging-spectroscopic data produced by the Chandra X-ray Observatory, we report new evidence for the existence of a parsec-scale jet from Sgr A*, by associating a linear feature G359.944-0.052, previously identified in X-ray images of the Galactic Center, with a radio shock front on the Eastern Arm of the Sgr A West HII region. We show that the shock front can be explained in terms of the impact of a jet having a sharp momentum peak along the Galaxy's rotation axis, whereas G359.944-0.052, a quasi-steady feature with a power-law spectrum, can be understood as synchrotron radiation from shock-induced ultrarelativistic electrons cooling in a finite post-shock region downstream along the jet path. Several interesting implications of the jet properties are discussed.

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Zhiyuan Li, Mark R. Morris, Frederick K. Baganoff. 2013-10-01. Evidence for A Parsec-scale Jet from The Galactic Center Black Hole: Interaction with Local Gas. https://doi.org/10.1088/0004-637x/779/2/154

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