How to hide large-scale outflows: size constraints on the jets of Sgr A*
Abstract
Despite significant strides made towards understanding accretion, outflow and emission processes in the Galactic Centre supermassive black hole Sagittarius A*, the presence of jets has been neither rejected nor proven. We investigate here whether the combined spectral and morphological properties of the source at radio through near-infrared wavelengths are consistent with the predictions for inhomogeneous jets. In particular, we construct images of jets at a wavelength of 7 mm based on models that are consistent with the spectrum of Sgr A*. We then compare these models through closure quantities with data obtained from the Very Long Baseline Array at 7 mm. We find that the best-fitting jet models give comparable or better fits than the best-fitting Gaussian models for the intrinsic source found in previous analyses. The best-fitting jet models are bipolar, are highly inclined to the line of sight (θ >~ 75°), may favour a position angle on the sky of 105°, and have compact bases with sizes of a few gravitational radii.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- August 2007
- DOI:
- 10.1111/j.1365-2966.2007.12071.x
- arXiv:
- arXiv:astro-ph/0702637
- Bibcode:
- 2007MNRAS.379.1519M
- Keywords:
-
- black hole physics;
- radiation mechanisms: non-thermal;
- Galaxy: nucleus;
- galaxies: active;
- galaxies: jets;
- Astrophysics
- E-Print:
- 12 pages, 14 figures, submitted to MNRAS