具有两个临界点的径移主导吸积流整体解  

Global Solutions of advection-Dominated Accretion Flows with Two Critical Points

作　　者：顾为民[1] 卢炬甫[2] 

机构地区：[1]中国科学技术大学天体物理中心 [2]厦门大学物理系,厦门361005

出　　处：《天文学报》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

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.

关 键 词：黑洞 吸积盘 流体动力学 粘滞系数 标准薄盘模型 松驰法 

分 类 号：P145.8[天文地球—天体物理]