Luminous Hot Accretion Flows: Thermal Equilibrium Curve and Thermal Stability
نویسندگان
چکیده
منابع مشابه
Luminous hot accretion flows: thermal equilibrium curve and thermal stability
In a previous paper, we presented the global solution of a new accretion flow model, namely luminous hot accretion flows (LHAFs). In this Letter, we first show the corresponding thermal equilibrium curve of LHAFs in the mass accretion rate vs. surface density diagram. Then we examine its thermal stability again local perturbations. We find that LHAFs are thermally unstable when thermal conducti...
متن کاملThermal Conduction and the Stability of Hot Accretion Flows
Recently, Medvedev & Narayan (2001) discovered a new type of accretion flow, a hot settling flow around a rapidly rotating neutron star. The flow is cooling-dominated and energetically similar to the Shapiro, Lightman, & Eardley (1976, SLE) solution. Since the SLE solution is known to be thermally unstable, one might suspect that the new solution would also be unstable. However, due to the very...
متن کاملHybrid Thermal-Nonthermal Synchrotron Emission from Hot Accretion Flows
We investigate the effect of a hybrid electron population, consisting of both thermal and non-thermal particles, on the synchrotron spectrum, image size, and image shape of a hot accretion flow onto a supermassive black hole. We find two universal features in the emitted synchrotron spectrum: (i) a prominent shoulder at low (∼< 10 11 Hz) frequencies that is weakly dependent on the shape of the ...
متن کاملLuminous hot accretion disks
We find a new two-temperature hot branch of equilibrium solutions for stationary accretion disks around black holes. In units of Eddington accretion rate defined as 10LEdd/c , the accretion rates to which these solutions correspond are within the range ṁ1 <∼ ṁ <∼ 1, here ṁ1 is the critical rate of advection-dominated accretion flow (ADAF). In these solutions, the energy loss rate of the ions by...
متن کاملHot accretion discs with thermal Comptonisation and advection in luminous black hole sources
We solve for the structure of a hot accretion disc with unsaturated thermal Comptonisation of soft photons and with advection, generalizing the classical model of Shapiro et al. The upper limit on the accretion rate due to advection constrains the luminosity to < ∼ 0.15y 3/5 α 7/5 of the Eddington limit, where y and α are the Compton and viscosity parameters, respectively. The characteristic te...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2003
ISSN: 0004-637X,1538-4357
DOI: 10.1086/378666