Einstein@Home在PALFA巡天中发现双中子星双星
Einstein@Home discovery of a Double-Neutron Star Binary in the PALFA Survey
摘要：
我们在这里报告Einstein@Home发现PSR J1913+1102，这是一颗27.3毫秒的脉冲星，发现于正在进行的Arecibo PALFA脉冲星调查的数据中。该脉冲星位于一个4.95小时的双中子星（DNS）系统中，偏心率为0.089。利用Arecibo 305米望远镜的射电计时，我们测得近星点的前进速率为5.632（18）度/年。假设广义相对论精确地模拟了轨道运动，这相当于系统的总质量为2.875（14）太阳质量，与迄今已知的最大质量的DNS B1913+16的质量相似，但离心率要小得多。小的离心率表明，第二次形成的中子星（PSR J1913+1102的伴星）诞生于一颗超新星，伴随着非常小的反冲和质量损失。在这种情况下，这个伴星很可能是一颗轻（1.2太阳质量）的中子星，因此这个系统是高度不对称的。对伴星无线电脉冲的搜索没有发现任何合理的探测结果，所以我们还不能证实这种质量不对称。到2016年底，定时观测应能探测到另外两个后开普勒参数：爱因斯坦延迟，这将使精确的质量测量和验证系统可能的质量不对称性成为可能;以及由于发射引力波而引起的轨道衰减，这将使对引力辐射特性的另一次测试成为可能。后一种效应将导致系统在~0.5 Gyr内合并。
英文摘要：
We report here the Einstein@Home discovery of PSR J1913+1102, a 27.3-ms pulsar found in data from the ongoing Arecibo PALFA pulsar survey. The pulsar is in a 4.95-hr double neutron star (DNS) system with an eccentricity of 0.089. From radio timing with the Arecibo 305-m telescope, we measure the rate of advance of periastron to be 5.632(18) deg/yr. Assuming general relativity accurately models the orbital motion, this corresponds to a total system mass of 2.875(14) solar masses, similar to the mass of the most massive DNS known to date, B1913+16, but with a much smaller eccentricity. The small eccentricity indicates that the second-formed neutron star (the companion of PSR J1913+1102) was born in a supernova with a very small associated kick and mass loss. In that case this companion is likely, by analogy with other systems, to be a light (1.2 solar mass) neutron star; the system would then be highly asymmetric. A search for radio pulsations from the companion yielded no plausible detections, so we can't yet confirm this mass asymmetry. By the end of 2016, timing observations should permit the detection of two additional post-Keplerian parameters: the Einstein delay, which will enable precise mass measurements and a verification of the possible mass asymmetry of the system, and the orbital decay due to the emission of gravitational waves, which will allow another test of the radiative properties of gravity. The latter effect will cause the system to coalesce in ~0.5 Gyr.
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。
