arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2110.09604astro-ph.HEastro-ph.GAgr-qc
收藏

黑洞-中子星合并不太可能是多信使源

Black hole-neutron star mergers are unlikely multi-messenger sources

Giacomo Fragione

摘要:

LIGO/Virgo/Kagra(LVK)合作通过引力波(GW)发射探测黑洞-中子星(BH-NS)合并的承诺最近已经实现,探测到了GW 200105和GW 200115。BH-NS双星的合并特别令人兴奋的是它们的多信使潜力,因为GW检测可以通过电磁(EM)对应物(千诺瓦,伽马射线暴,余辉),可以揭示关于NS状态方程(EOS)和BH自旋性质的重要信息。我们进行了统计研究的双星,演变形成一个BH-NS二进制和计算合并事件,可以遵循EM对应的速率。我们发现,$\gtrsim 50\%$的合并可以导致EM对应物的情况下,黑洞出生高自旋($χ_{\rm BH}\gtrsim 0.7$),而这一部分不超过约$30\%$刚性NS EOS和几个百分点的软NS EOS低自旋黑洞($χ_{\rm BH}\lesssim 0.2$),这表明高比率的EM对应物的BH-NS将提供支持高出生BH自旋。然而,可能性的BH出生与近最大的自旋和NS的内部结构是由一个僵硬的EOS是不利的,目前LVK的限制。考虑到这些值只代表一个上限,以观察一个EM对应由于目前的观测限制,如在亮度灵敏度和天空定位,BH-NS合并是不太可能的多信使来源。

英文摘要:

The promise by the LIGO/Virgo/Kagra (LVK) collaboration to detect black hole--neutron star (BH--NS) mergers via gravitational wave (GW) emission has recently been fulfilled with the detection of GW200105 and GW200115. Mergers of BH--NS binaries are particularly exciting for their multi-messenger potential, since the GW detection can be followed by an electromagnetic (EM) counterpart (kilonova, gamma-ray burst, afterglow) that can reveal important information on the equation of state (EOS) of NSs and the nature of the BH spin. We carry out a statistical study of the binary stars that evolve to form a BH--NS binary and compute the rate of merger events that can be followed by an EM counterpart. We find that $\gtrsim 50\%$ of the mergers can lead to an EM counterpart only in the case BHs are born highly spinning ($χ_{\rm BH}\gtrsim 0.7$), while this fraction does not exceed about $30\%$ for stiff NS EOSs and a few percent for soft NS EOSs for low-spinning BHs ($χ_{\rm BH}\lesssim 0.2$), suggesting that a high rate of EM counterparts of BH--NS would provide support for high natal BH spins. However, the possibilities that BHs are born with near-maximal spins and that NS internal structure is described by a stiff EOS are disfavored by current LVK constraints. Considering that these values only represent an upper limit to observe an EM counterpart due to current observational limitations, as in brightness sensitivity and sky localization, BH--NS mergers are unlikely multi-messenger sources.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑