Advection-dominated Accretion: A Self-similar Solution (original) (raw)
ADS
Abstract
We consider viscous rotating accretion flows in which most of the viscously dissipated energy is stored as entropy rather than being radiated. Such advection-dominated flows may occur when the optical depth is either very small or very large. We obtain a family of self-similar solutions where the temperature of the accreting gas is nearly virial and the flow is quasi-spherical. The gas rotates at much less than the Keplerian angular velocity; therefore, the central stars in such flows will cease to spin up long before they reach the break-up limit. Further, the Bernoulli parameter is positive, implying that advection-dominated flows are susceptible to producing outflows. Convection is likely in many of these flows and, if present, will tend to enhance the above effects. We suggest that advection-dominated accretion may provide an explanation for the slow spin rates of accreting stars and the widespread occurrence of outflows and jets in accreting systems.
Publication:
The Astrophysical Journal
Pub Date:
June 1994
DOI:
10.48550/arXiv.astro-ph/9403052
arXiv:
Bibcode:
Keywords:
- Accretion Disks;
- Advection;
- Astronomical Models;
- Black Holes (Astronomy);
- Cooling Flows (Astrophysics);
- Stellar Mass Accretion;
- Viscous Flow;
- Hydrodynamics;
- Rotating Disks;
- Two Dimensional Flow;
- Astrophysics;
- ACCRETION;
- ACCRETION DISKS;
- BLACK HOLE PHYSICS;
- HYDRODYNAMICS;
- Astrophysics
E-Print:
7 pages of text, 1 postscript figure, plain TeX, Harvard-Smithsonian Center for Astrophysics Preprint Series No. 3809