RADIATIVE-HYDRODYNAMICAL SIMULATIONS OF ACCRETION DISK CORONAE

被引:13
作者
MELIA, F
ZYLSTRA, GJ
FRYXELL, B
机构
[1] UNIV ARIZONA,DEPT PHYS,TUCSON,AZ 85718
[2] UNIV ARIZONA,STEWARD OBSERV,TUCSON,AZ 85724
关键词
BLACK HOLES; RADIATIVE TRANSFER; STARS; ACCRETION; BINARIES; CORONAE; NEUTRON;
D O I
10.1086/186126
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We have developed an algorithm that will carry out detailed, two-dimensional, fully self-consistent radiative-hydrodynamical simulations of accretion disk coronae in X-ray-luminous compact sources. The calculation reported here, for an accreting neutron star radiating at 0.5 times the Eddington luminosity, reveals several striking features. (1) The corona is comprised of two main regions - an inner (r less-than-or-similar-to 1 x 10(8) cm) highly dynamic portion whose vertical structure varies cyclically on a dynamical time scale (approximately 0.2 s), and an outer, more stable zone in which the evaporated plasma rises to form a "sheath" that gradually merges into a wind at large radii. (2) The coronal structure shows a density inversion (due to the ram pressure support of the ionized flow) that contrasts sharply with the Gaussian profiles of earlier hydrostatic models. (3) Interestingly, flow velocities as high as a few x 10(9) cm s-1 are not uncommon in portions of the corona. We discuss the relevance of this point to the large measured width of the emission features seen in low-mass X-ray binaries and the Galactic black hole candidates.
引用
收藏
页码:L101 / &
相关论文
共 31 条
[1]   THE DISCOVERY OF LOW-LEVEL IRON-K LINE EMISSION FROM CYG X-1 [J].
BARR, P ;
WHITE, NE ;
PAGE, CG .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1985, 216 (03) :P65-P70
[2]   COMPTON HEATED WINDS AND CORONAE ABOVE ACCRETION DISKS .1. DYNAMICS [J].
BEGELMAN, MC ;
MCKEE, CF ;
SHIELDS, GA .
ASTROPHYSICAL JOURNAL, 1983, 271 (01) :70-88
[3]   THE PIECEWISE PARABOLIC METHOD (PPM) FOR GAS-DYNAMICAL SIMULATIONS [J].
COLELLA, P ;
WOODWARD, PR .
JOURNAL OF COMPUTATIONAL PHYSICS, 1984, 54 (01) :174-201
[4]   THEORETICAL SPECTRA OF NONMAGNETIZED LOW-MASS X-RAY BINARIES [J].
CZERNY, B ;
CZERNY, M ;
GRINDLAY, JE .
ASTROPHYSICAL JOURNAL, 1986, 311 (01) :241-257
[5]  
FABIAN A, 1986, MNRAS, V208, P457
[6]   DISCOVERY OF AN X-RAY BURST FROM 4U-2129+47 [J].
GARCIA, MR ;
GRINDLAY, JE .
ASTROPHYSICAL JOURNAL, 1987, 313 (02) :L59-L64
[7]  
ICKE V, 1976, IAU S, V73, P267
[8]  
JONES C, 1976, ASTROPHYS J, V209, pL131, DOI 10.1086/182283
[9]  
KAKUBARI K, 1989, PUBL ASTRON SOC JPN, V41, P1035
[10]   IRON-K LINES FROM LOW-MASS X-RAY BINARIES [J].
KALLMAN, T ;
WHITE, NE .
ASTROPHYSICAL JOURNAL, 1989, 341 (02) :955-960