arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1808.04822astro-ph.HEastro-ph.SRgr-qc
收藏

快速射电暴是最可能的电磁对应物的中子星合并导致迅速崩溃?

Are fast radio bursts the most likely electromagnetic counterpart of neutron star mergers resulting in prompt collapse?

Vasileios Paschalidis, Milton Ruiz

摘要:

吸合中子星是引力波和电磁波的重要来源。如果BNS的总质量大于一个阈值,黑洞在合并后会迅速膨胀。通过统计研究结合最近的LIGO/室女座约束核状态方程,我们估计,高达$\sim 25\%$的BNS合并可能会导致迅速崩溃。此外,我们发现,大多数模型的BNS质量函数,我们在这里研究预测,大多数的BNS合并的非崩溃有$q\gtrsim 0.8$。质量比为$q \gtrsim 0.8$的BNS坍缩合并可能不会伴随着可检测的千诺瓦或短伽马射线爆发,因为它们释放了可忽略不计的质量,并在残余黑洞上形成了可忽略不计的小吸积盘。我们称这种BNS合并为“孤儿”。然而,最近的研究发现,${10^{41-43}(B_p/10^{12}\rm G)^2 erg\, s^{-1}}$电磁信号可以由合并前几毫秒的磁层相互作用提供动力。此外,储存在孤立的BNS合并残留物的磁层中的能量将在${\mathcal O}(1\ \rm ms)$中辐射出去。通过对初始磁层为偶极的BNS系统的全广义相对论模拟,我们发现黑洞形成后磁层中的能量为$E_B \sim 10^{39-41} (B_p/10^{12}\rm G)^2$ erg。正如先前的研究所发现的,$E_B$在1毫秒内的辐射$\sim 1\%$与合并前磁层光度相匹配。这些磁层信号没有被发射,其持续时间和功率与非重复的快速射电暴(FRB)一致。这些结果结合我们的统计研究表明,一个非重复的FRB可能是最有可能的电磁对应的非崩溃BNS。

英文摘要:

Inspiraling and merging binary neutron stars (BNSs) are important sources of both gravitational waves and coincident electromagnetic counterparts. If the BNS total mass is larger than a threshold value, a black hole ensues promptly after merger. Through a statistical study in conjunction with recent LIGO/Virgo constraints on the nuclear equation of state, we estimate that up to $\sim 25\%$ of BNS mergers may result in prompt collapse. Moreover, we find that most models of the BNS mass function we study here predict that the majority of prompt-collapse BNS mergers have $q\gtrsim 0.8$. Prompt-collapse BNS mergers with mass ratio $q \gtrsim 0.8$ may not be accompanied by detectable kilonovae or short gamma-ray bursts, because they unbind a negligible amount of mass and form negligibly small accretion disks onto the remnant black hole. We call such BNS mergers "orphan". However, recent studies have found that ${10^{41-43}(B_p/10^{12}\rm G)^2 erg\, s^{-1}}$ electromagnetic signals can be powered by magnetospheric interactions several milliseconds prior to merger. Moreover, the energy stored in the magnetosphere of an orphan BNS merger remnant will be radiated away in ${\mathcal O}(1\ \rm ms)$. Through simulations in full general relativity of BNSs endowed with an initial dipole magnetosphere, we find that the energy in the magnetosphere following black hole formation is $E_B \sim 10^{39-41} (B_p/10^{12}\rm G)^2$ erg. Radiating $\sim 1\%$ of $E_B$ in 1 ms, as has been found in previous studies, matches the premerger magnetospheric luminosity. These magnetospheric signals are not beamed, and their duration and power agrees with those of non-repeating fast radio bursts (FRBs). These results combined with our statistical study suggest that a non-repeating FRB may be the most likely electromagnetic counterpart of prompt-collapse BNSs.

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。

↑