论文标题
二进制进化导致在J0740+6620二进制系统中形成非常庞大的中子星
Binary evolution leading to the formation of the very massive neutron star in the J0740+6620 binary system
论文作者
论文摘要
我们研究了近二进制系统的演变，以说明最近观察到的二进制系统的存在，该系统包含有史以来检测到的最巨大的脉冲星，PSR J0740+6620及其超冷的氦白矮人伴侣。为了找到该对象的祖细胞，我们计算了由中子星和正常供体星组成的几种二进制系统的演变，该系统采用了我们的出色代码。我们假设保守的传质。我们还探讨了辐射反馈对系统的影响。我们发现，辐照模型还为毫秒的脉冲星及其伴侣提供了足够的模型，因此辐照和非辐照系统都是PSR J0740+6620的良好祖细胞。最后，我们获得了一个二进制系统，该系统在PSR J0740+6620（即轨道周期，质量，有效温度和伴侣的质量和中子星的质量）中进化并解释了由PSR J0740+6620组成的观察数据，以及中性恒星的质量），在小于宇宙年龄的时间尺度上。为了达到所观察到的有效温度，供体恒星应按照观测值的要求具有氦象围座。
We study the evolution of close binary systems in order to account for the existence of the recently observed binary system containing the most massive millisecond pulsar ever detected, PSR J0740+6620, and its ultra-cool helium white dwarf companion. In order to find a progenitor for this object we compute the evolution of several binary systems composed by a neutron star and a normal donor star employing our stellar code. We assume conservative mass transfer. We also explore the effects of irradiation feedback on the system. We find that irradiated models also provide adequate models for the millisecond pulsar and its companion, so both irradiated and non irradiated systems are good progenitors for PSR J0740+6620. Finally, we obtain a binary system that evolves and accounts for the observational data of the system composed by PSR J0740+6620 (i.e. orbital period, mass, effective temperature and inferred metallicity of the companion, and mass of the neutron star) in a time scale smaller than the age of the Universe. In order to reach an effective temperature as low as observed, the donor star should have an helium envelope as demanded by observations.
