论文标题
来自年轻明星集群中高巨星二元分数的中等质量黑洞
Intermediate-mass Black Holes from High Massive-star Binary Fractions in Young Star Clusters
论文作者
论文摘要
在密集的星形簇中形成的黑孔，在该恒星簇中频繁进行动态相互作用，可能具有与通过孤立的恒星进化形成的黑洞具有根本不同的特性。单星进化的理论模型可预测黑洞质谱的差距，大约是$ 40-120 \，m _ {\ odot} $由（脉动）配对超级novae引起的。在最近的Ligo/处女座事件GW190521中，我们调查了在这种“上层质量差异”内或超过质量的黑洞是否可以通过在二进制室中的巨大恒星的强烈相互作用在年轻的恒星簇中动态形成。我们使用CMC群集 - 动力学代码执行一组$ n $体体模拟，以研究高质量二元分数对最大恒星及其残余物的形成和碰撞历史的影响。我们发现，典型的年轻恒星簇具有低金属性和巨大恒星中高二元分数的典型年轻簇可以在上质量间隙中形成几个黑洞，并且通常形成至少一个中间质量的黑洞。这些结果提供了有力的证据，表明年轻恒星簇的动态相互作用自然会导致形成更大的黑洞残留物。
Black holes formed in dense star clusters, where dynamical interactions are frequent, may have fundamentally different properties than those formed through isolated stellar evolution. Theoretical models for single star evolution predict a gap in the black hole mass spectrum from roughly $40-120\,M_{\odot}$ caused by (pulsational) pair-instability supernovae. Motivated by the recent LIGO/Virgo event GW190521, we investigate whether black holes with masses within or in excess of this "upper-mass gap" can be formed dynamically in young star clusters through strong interactions of massive stars in binaries. We perform a set of $N$-body simulations using the CMC cluster-dynamics code to study the effects of the high-mass binary fraction on the formation and collision histories of the most massive stars and their remnants. We find that typical young star clusters with low metallicities and high binary fractions in massive stars can form several black holes in the upper-mass gap and often form at least one intermediate-mass black hole. These results provide strong evidence that dynamical interactions in young star clusters naturally lead to the formation of more massive black hole remnants.
