自引力磁均分和磁守恒吸积盘模型的稳定性分析  

STABILITY OF THE MAGNETO-EQUIPARTITION MODEL AND MAGNETO-CONSERVATION MODEL OF ACCRETION DISKS WITH SELF-GRAVITATION

作　　者：陆烨[1] 杨兰田[1] 汪定雄[2] 

机构地区：[1]华中师范大学物理系天体物理所,武汉430079 [2]华中理工大学物理系,武汉430074

出　　处：《天文学报》1998年第3期271-277,共7页Acta Astronomica Sinica

基　　金：国家自然科学基金;国家攀登计划

摘　　要：对自引力磁均分和磁守恒两种模型的径向振荡稳定性的研究表明：在同时考虑自引力和磁场作用的情况下，吸积盘在磁均分和磁守恒模型中均存在着三种振荡模式，其中粘滞模式总是稳定的，磁声模式是不稳定的，中性模式在图中较长波段范围趋于稳定，在较短波段范围是不稳定的．这些结果有利于解释活动天体的Mark421和Pks2155—304的长周期光变现象．同时阐明了自引力在两种模型中对三种模式的影响有相同的趋势，而对磁场则分别起着相反的作用．这个结论表明磁均分吸积盘模型在解释光变现象时更为有利．The radial oscillation instability of both magneto-equipartition model and magneto-conservation model of accretion disks with self-gravitation is examined in this paper. Our results show that there are three modes in the disk. The viscous mode is always stable, the magneto-acoustic one is unstable and the neutral one tends to be stable in long wavelength region, but unstable in short wavelength region. Meanwhile,the effects of self-gravitation for the three modes are similar in both models, but the effects of the magnetic field are opposite. These results imply that the magneto-equpartition model is the best one for explaining the bine variations of X-ray stars and AGNs.

关 键 词：吸积 吸积盘 磁流体力学 不稳定性 自引力磁均分 

分 类 号：P145.8[天文地球—天体物理]