Red giant disk encounters: Food for quasars?

被引:32
作者
Armitage, PJ [1 ]
Zurek, WH [1 ]
Davies, MB [1 ]
机构
[1] LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA
关键词
galaxies; active; hydrodynamics; methods; numerical; stars; kinematics; mass loss;
D O I
10.1086/177864
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We explore the role that red giants might play in the fueling and evolution of active galactic nuclei (AGNs). Due to their large radii and the low binding energy of the stellar envelope, giants are vulnerable to envelope stripping from collisions with the accretion disk. Using hydrodynamic simulations, we show that such collisions will typically deposit a substantial fraction of the envelope mass into the disk on each passage. Repeated encounters will then lead to the complete destruction of the star save for the dense core. We estimate the rate of fuel supply by this mechanism using simple models for the AGN disk and central stellar cluster. If the central stellar density is similar to 10(7) M. pc(-3), then stripping of giants could account for the activity of typical AGNs provided that the accretion disk extends out to similar to 0.1 pc. For AGNs with smaller disks, or clusters of lower central density, giant stripping could supply gas enriched via stellar nucleosynthesis to a disk replenished from some other source. We find that, for typical parameters, this mechanism is able to supply important quantities of gas to the disk at lower stellar densities than previously proposed stellar fueling models for AGNs.
引用
收藏
页码:237 / 248
页数:12
相关论文
共 35 条
  • [31] THE EVOLUTION OF IRRADIATED STARS
    TOUT, CA
    EGGLETON, PP
    FABIAN, AC
    PRINGLE, JE
    [J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1989, 238 (01) : 427 - 438
  • [32] SUPERNOVAE IN BINARY-SYSTEMS
    WHEELER, JC
    LECAR, M
    MCKEE, CF
    [J]. ASTROPHYSICAL JOURNAL, 1975, 200 (01) : 145 - 157
  • [33] STAR-DISK COLLISIONS AND THE ORIGIN OF THE BROAD LINES IN QUASARS
    ZUREK, WH
    SIEMIGINOWSKA, A
    COLGATE, SA
    [J]. ASTROPHYSICAL JOURNAL, 1994, 434 (01) : 46 - 53
  • [34] ZUREK WH, 1996, UNPUB APJ
  • [35] ZUREK WH, 1991, AIP C P, V254, P564