摘要
对黑洞径移主导吸积流(ADAF)的整体解作了研究.整体解经过两个临界点, 其中一个是声速点Rs;另一个是粘滞点Rv, 解被两个临界点划分为3个区域;亚声速有 粘滞的外区(R>Rv),亚声速无粘滞的中间区(Rs<R<Rv)和超声速无粘滞的内区 (R<Rs).展示了一个完整的Rs-j参数空间图,它显示了所有可能的ADAF解.共发 现3种类型的整体解:ADAF-标准薄盘解、ADAF-厚盘解和含α-X型绝热激波的 解,并给出了ADAF-标准薄盘解中Rs、Rv和Rout(ADAF的外边界)之间的一一对应 关系.绝热激波将一个X型解的超声速无粘滞区域连接到一个α型解的亚声速无粘滞区 域.这样的激波发生在两个无粘滞的区域之间,它能存在于各种大小的粘滞系数的ADAF 中.
Global solutions of advection dominated accretion- flows (ADAFs) around black holes are presented. The global solution passes through two critical points, one of which is the sonic point R~, and the other of which is the viscous point Rs. Thus the solution is divided by the two critical points into three radial zones: the subsonic, subviscous outer zone, (R > Ru), the subsonic, superviscous middle zone, (Rs < R < Re), and the supersonic, superviscous inner zone, (R < Rv). A complete picture in Rs-j parameter space is obtained which sums up the situation of ADAF solutions. Three classes of global solutions are found: the ADAF-thin disk solution, the ADAF-thick disk solution and the a - X type adiabatic shock-included solution. We also present the unique correspondence among Rs, Rv and Rout of ADAF-thin disk solutions, where R0~~ is the outer boundary of ADAF. The adiabatic shock in the accretion flow connects the supersonic, superviscous zone of an X-type solution to the subsonic, superviscous zone of an a-type soultion. Because the shock occurs between two superviscous zones, it can exist in flows with either low or high viscosity.
出处
《天文学报》
CSCD
北大核心
2002年第1期15-23,共9页
Acta Astronomica Sinica
基金
国家自然科学基金项目(No.10073010)资助