Jets at lowest mass accretion rates
Abstract
We present results of recent observations and theoretical modeling of data from black holes accreting at very low luminosities (L/LEdd <~ 10-8). We discuss our newly developed time-dependent model for episodic ejection of relativistic plasma within a jet framework, and a successful application of this model to describe the origin of radio flares seen in Sgr A*, the Galactic center black hole. Both the observed time lags and size-frequency relationships are reproduced well by the model. We also discuss results from new Spitzer data of the stellar black hole X-ray binary system A0620-00. Complemented by long term SMARTS monitoring, these observations indicate that once the contribution from the accretion disk and the donor star are properly included, the residual mid-IR spectral energy distribution of A0620-00 is quite flat and consistent with a non-thermal origin. The results above suggest that a significant fraction of the observed spectral energy distribution originating near black holes accreting at low luminosities could result from a mildly relativistic outflow. The fact that these outflows are seen in both stellar-mass black holes as well as in supermassive black holes at the heart of AGNs strengthens our expectation that accretion and jet physics scales with mass.
- Publication:
-
Jets at All Scales
- Pub Date:
- February 2011
- DOI:
- 10.1017/S174392131001567X
- arXiv:
- arXiv:1010.4296
- Bibcode:
- 2011IAUS..275...82M
- Keywords:
-
- black hole physics;
- accretion;
- accretion disks;
- acceleration of particles;
- Galaxy: nucleus;
- radiation mechanisms: general;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 4 pages, 2 figures. To appear in Proceedings of IAU Symposium 275 "Jets at all Scales", 13-17 September 2010, Buenos Aires, Argentina