论文标题
测量黑寡妇PSR J1555-2908的质量
Measuring the mass of the black widow PSR J1555-2908
论文作者
论文摘要
对于测试二进制演化模型并限制状态的中子恒星方程，需要准确测量中子星的质量。在没有可测量的二元后参数的脉冲星二进制物中，这需要通过其他方式以其他方式对伴侣恒星的倾斜度进行准确估计。在本文中，我们介绍了一种使用二进制合成代码伊卡洛斯（Icarus）测量径向速度的新方法的结果。此方法依靠为给定的二进制配置构建潮汐变形的，受辐照的星的模型光谱。该方法应用于新发现的黑寡妇PSR J1555-2908的光谱。通过与光学光度法一起建模光谱法，我们发现，伴侣星的径向速度为$ 397 \ pm4 $ km s $ s $^{ - 1} $（以95 \％置信区间引用错误），以及$> 75^{\ rm o o} $ of $> 75^{\ rm o}的二进制倾斜度。 Combined with $γ$-ray pulsation timing information, this gives a neutron star mass of 1.67$^{+0.15}_{-0.09}$ M$_\odot$ and a companion mass of 0.060$^{+0.005}_{-0.003}$ M$_\odot$, placing PSR J1555-2908 at the observed upper limit of被认为是黑寡妇系统。
Accurate measurements of the masses of neutron stars are necessary to test binary evolution models, and to constrain the neutron star equation of state. In pulsar binaries with no measurable post-Keplerian parameters, this requires an accurate estimate of the binary system's inclination and the radial velocity of the companion star by other means than pulsar timing. In this paper, we present the results of a new method for measuring this radial velocity using the binary synthesis code Icarus. This method relies on constructing a model spectrum of a tidally distorted, irradiated star as viewed for a given binary configuration. This method is applied to optical spectra of the newly discovered black widow PSR J1555-2908. By modelling the optical spectroscopy alongside optical photometry, we find that the radial velocity of the companion star is $397\pm4$ km s$^{-1}$ (errors quoted at 95\% confidence interval), as well as a binary inclination of $>75^{\rm o}$. Combined with $γ$-ray pulsation timing information, this gives a neutron star mass of 1.67$^{+0.15}_{-0.09}$ M$_\odot$ and a companion mass of 0.060$^{+0.005}_{-0.003}$ M$_\odot$, placing PSR J1555-2908 at the observed upper limit of what is considered a black widow system.
