摘要
与吸积率和爱丁顿吸积率的比率一道,黑洞质量也是活动星系核的一个基本参数。我们采用谢光中等的新方法去估计了21个blazar样本的黑洞质量(MH),同时运用了MBH-σ相关分析方法来估计同一个blazar样本的黑洞质量(Mσ),通过对两种不同方法所得样本黑洞质量的比较,我们发现(1)MH系统的小于Mσ,但是对于大多数blazar样本来说Mσ和MH之间的差别很小;(2)在Mσ和MH之间存在着一个有意义的相关性,相关系数为r=0.832,p≤1.0×10-4。以上述的这些性质和活动星系核标准模型为基础,我们证明了这两种方法所得的黑洞质量Mσ和MH之间的系统差异是因为Mσ描述的是宽发射线区(r≤rb)的黑洞质量,而MH描述的是黑洞周围在最内层轨道附近的连续发射区的质量。这就是说Mσ应该是被过度估计了。由Mσ和中心黑洞质量MH*的关系,我们再次计算中心黑洞质量MH*,并且发现中心黑洞质量MH*和MH几乎是相同的。
Black hole mass, along with the ratio of the accretionrate to the Eddington accretion rate, is a fundamental parameter of active galactic nuclei （AGNs）. Using Xie＇ s method of the black mass estimate, we developed our sample and estimated the black hole masses represented by MH for 21 blazars. We compare 21 cases for each of which the relevant black hole mass has been also estimated by the MBH - σ correlation method , which is represented by Mσ. And we find that （ 1 ） MH are systematically lower than Mσ, but the differences between Mσ and MH are very small for most of the sources; （2） there is a significant correlation between Mσ and MH, the correlation coefficient r = 0. 823 with chance probability p - 1.0 × 10^- 4. Based on these properties mentioned above and the standard model of AGNs, we prove that the nature of the systematical difference between Mσ and MH is that Mσ represents the mass in broad emission line region （ r ≤rb ）, while MH represents the mass in the continual emission region （ r≤ra and ra≤rb） which is near the innermost stable orbit around the black hole. That is, M^＊H would be overestimated. From Mσ, we calculate the central black hole mass again, which is indicated by M^＊H, and find that M^＊H is almost equal to the correspondent MH.
出处
《天文研究与技术》
CSCD
北大核心
2007年第2期113-120,共8页
Astronomical Research & Technology
基金
云南省自然科学基金(04A0015Q)资助
关键词
星系
活动星系核
基本参数
黑洞质量
active glactic nuclei
fundamental parameters
black hole mass
