论文标题
超矮星系合并的GW190521
GW190521 from the Merger of Ultra-Dwarf Galaxies
论文作者
论文摘要
我们为引力波事件GW190521提供了一种替代形态场景，可以解释为在两个超弱质量$ \ sim $ \ sim 10^5-10^6〜m_ \ odot $的合并中的中央黑洞的中央黑洞，这本身以前合并了。 GW190521组件的质量为$ 85^{+21} _ { - 14} m_ \ odot $和$ 66^{+17} _ { - 18} m_ \ odot $挑战标准恒星演变模型，因为它们落在所谓的质量质量上。我们证明，高红移（$ 1 \ Lessim z \ Lessim 2 $ 2 $）的超贫困星系的合并历史与GW190521质量范围内的黑洞的合并率很好地匹配了GW190521组件的合并速率，从而导致可能的时间延迟$ \ lyssim 4 $ 4 $ gyr this this this this of Redshift of Redshiff this Redshiff indsim of Redshiff indshiff indsif this Redshift redshiff。我们进一步证明，预测的时间尺度与中央黑洞合并的期望是一致的，尽管由于缺乏低质量矮人星系中的高分辨率模拟，因此不确定性很大。我们的发现表明，这种黑洞的生产和合并通道是可行的，并且非常有趣，这是一种探索星系黑洞种子和星系形成的新方法。我们建议通过模拟和观察详细研究这种情况。
We present an alternative formation scenario for the gravitational wave event GW190521, that can be explained as the merger of central black holes from two ultra-dwarf galaxies of stellar mass $\sim 10^5-10^6 ~M_\odot$, which had themselves previously undergone a merger. The GW190521 components' masses of $85^{+21}_{-14}M_\odot$ and $66^{+17}_{-18}M_\odot$ challenge standard stellar evolution models, as they fall in the so-called mass gap. We demonstrate that the merger history of ultra-dwarf galaxies at high redshifts ($1\lesssim z \lesssim 2$) matches well the LIGO/Virgo inferred merger rate for black holes within the mass range of the GW190521 components, resulting in a likely time delay of $\lesssim 4$ Gyr considering the redshift of this event. We further demonstrate that the predicted time-scales are consistent with expectations for central black hole mergers, although with large uncertainties due to the lack of high-resolution simulations in low-mass dwarf galaxies. Our findings show that this black hole production and merging channel is viable and extremely interesting as a new way to explore galaxies' black hole seeds and galaxy formation. We recommend this scenario be investigated in detail with simulations and observations.
