Puffy Accretion Disks: Sub-Eddington, Optically Thick, and Stable

@article{38480,
   author = {Lančová, Debora and Abarca, David and Kluźniak, Włodek and Wielgus, Maciek and Sa̧dowski, Aleksander and Narayan, Ramesh and Schee, Jan and Török, Gabriel and Abramowicz, Marek},
   article_number = {2},
   doi = {http://dx.doi.org/10.3847/2041-8213/ab48f5},
   keywords = {accretion; magnetohydrodynamical simulations; general relativity; radiative magnetohydrodynamics; black holes},
   language = {eng},
   issn = {2041-8205},
   journal = {Astrophysical Journal Letters},
   title = {Puffy Accretion Disks: Sub-Eddington, Optically Thick, and Stable},
   url = {https://iopscience.iop.org/article/10.3847/2041-8213/ab48f5},
   volume = {884},
   year = {2019}
}

TY  - JOUR
ID  - 38480
AU  - Lančová, Debora - Abarca, David - Kluźniak, Włodek - Wielgus, Maciek - Sa̧dowski, Aleksander - Narayan, Ramesh - Schee, Jan - Török, Gabriel - Abramowicz, Marek
PY  - 2019
TI  - Puffy Accretion Disks: Sub-Eddington, Optically Thick, and Stable
JF  - Astrophysical Journal Letters
VL  - 884
IS  - 2
SP  - "L37-1"-"L37-6"
EP  - "L37-1"-"L37-6"
SN  - 20418205
KW  - accretion
KW  - magnetohydrodynamical simulations
KW  - general relativity
KW  - radiative magnetohydrodynamics
KW  - black holes
UR  - https://iopscience.iop.org/article/10.3847/2041-8213/ab48f5
L2  - https://iopscience.iop.org/article/10.3847/2041-8213/ab48f5
N2  - We report on a new class of solutions of black hole accretion disks that we have found through three-dimensional, global, radiative magnetohydrodynamic simulations in general relativity. It combines features of the canonical thin, slim, and thick disk models but differs in crucial respects from each of them. We expect these new solutions to provide a more realistic description of black hole disks than the slim disk model. We are presenting a disk solution for a nonspinning black hole at a sub-Eddington mass accretion rate, Mdot = 0.6 Mdot_Edd. By the density scale-height measure the disk appears to be thin, having a high density core near the equatorial plane of height h_rho ~ 0.1 r, but most of the inflow occurs through a highly advective, turbulent, optically thick, Keplerian region that sandwiches the core and has a substantial geometrical thickness comparable to the radius, H ~ r. The accreting fluid is supported above the midplane in large part by the magnetic field, with the gas and radiation to magnetic pressure ratio beta ~ 1, this makes the disk thermally stable, even though the radiation pressure strongly dominates over gas pressure. A significant part of the radiation emerging from the disk is captured by the black hole, so the disk is less luminous than a thin disk would be at the same accretion rate.
ER  - 

LANČOVÁ, Debora, David ABARCA, Włodek KLU$\backslash$'ZNIAK, Maciek WIELGUS, Aleksander SA̧DOWSKI, Ramesh NARAYAN, Jan SCHEE, Gabriel TÖRÖK and Marek ABRAMOWICZ. Puffy Accretion Disks: Sub-Eddington, Optically Thick, and Stable. \textit{Astrophysical Journal Letters}. 2019, vol.~884, No~2, p.~''L37-1''-''L37-6'', 6 pp. ISSN~2041-8205. Available from: https://dx.doi.org/10.3847/2041-8213/ab48f5.