Detecting stars at the galactic centre via synchrotron emission
Abstract
Stars orbiting within 1 arcsec of the supermassive black hole in the Galactic Centre, Sgr A*, are notoriously difficult to detect due to obscuration by gas and dust. We show that some stars orbiting this region may be detectable via synchrotron emission. In such instances, a bow shock forms around the star and accelerates the electrons. We calculate that around the 10 GHz band (radio) and at 1014 Hz (infrared) the luminosity of a star orbiting the black hole is comparable to the luminosity of Sgr A*. The strength of the synchrotron emission depends on a number of factors including the star's orbital velocity. Thus, the ideal time to observe the synchrotron flux is when the star is at pericentre. The star S2 will be ∼0.015 arcsec from Sgr A* in 2018, and is an excellent target to test our predictions.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- January 2016
- DOI:
- 10.1093/mnrasl/slv138
- arXiv:
- arXiv:1509.06251
- Bibcode:
- 2016MNRAS.455L..21G
- Keywords:
-
- black hole physics;
- radiation mechanisms: non-thermal;
- Galaxy: centre;
- Galaxy: kinematics and dynamics;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 5 pages, 3 figures, accepted for publication in MNRAS