黑洞双星的形成  

The Formation of Black-hole Binaries

作　　者：吴斌[1] 孟祥存[1] 韩占文[1] 

机构地区：[1]中国科学院国家天文台云南天文台

出　　处：《天文学报》2007年第2期121-129,共9页Acta Astronomica Sinica

基　　金：国家自然科学基金(10521001和10433030)资助

摘　　要：目前,观测证认的黑洞双星在黑洞质量分布上存在一峰值,但是还没有比较完备的理论可以解释,试图对该分布规律给出较合理的解释．鉴于恒星的氦(He)核在黑洞形成中所扮演角色的重要性,将He核质量与黑洞初始质量联系起来．根据Fryer等人的二维核塌缩模拟的结果,找到了一拟合关系,从而根据He核大小可以估算黑洞的初始质量．采用PPE恒星演化程序计算确定He核质量．最后得到星族Ⅱ和星族Ⅰ黑洞双星的黑洞初始质量的分布,并结合观测给出了相应的解释．A binary system which contains a massive primary star goes through a phase of common envelope and the less massive companion spirals-in thereafter. If the common envelope is ejected completely and the system avoids merging, it is possible to form a black hole binary. So far, to observe the black hole binaries is the only way to find out the stellarmass black holes effectively. It is important somewhat to study the formation of black hole binaries. The formation of black hole binaries is a very complex and difficult subject. It focuses on the masses of black holes in black hole binaries and their distribution only. According to the results of Fryer＇s two-dimensional core-collapse supernova simulations （TS） it is found that the relation between the explosion energy and the binding energy dominates the mass of remnant of primary star evolved in such a binary system as mentioned above. And then, on the one hand the binding energy lies on the mass of helium core strongly. The computing shows that the binding energy contributed by hydrogen shell is less than 10% of whole. On the other hand the explosion energy can be regarded as the function of the mass of helium core approximately. Thus it is found that the remnant mass may relate to the mass of helium core directly. It fits a quantitative relation between the mass of helium cores of black hole progenitors and the mass of black holes collapsed. The relation can be used more conveniently than TS＇s because of its simple form. Especially, it can be used in binary systems expediently. Combining with the PPE code, a theoretical distribution of the initial mass of black holes in binaries is gotten. At present, there are 17 candidates of black hole binaries in the data of observation and the distribution of the mass of these candidates shows that there is a peak around - 73M⊙. However, there is a difference between the shape of the theoretical distribution and the shape of observation. The theoretical distributional peak appears around - 53M⊙. But then, according

关 键 词：物理数据与过程 黑洞物理 恒星 演化 恒星 质量损失 恒星 星族Ⅱ 

分 类 号：P145[天文地球—天体物理]