论文标题
偏心毫秒的脉冲星，PSR J0955 $ - $ 6150 I：脉冲曲线分析，质量测量和二进制进化的约束
The eccentric millisecond pulsar, PSR J0955$-$6150 I: Pulse profile analysis, mass measurements and constraints on binary evolution
论文作者
论文摘要
PSR J0955 $ - $ 6150是一类偏心MSP+HE WD Systems（EMSP）的成员，其二进制进化的理解很差，并且被认为与传统的MSP+He WD系统不同。测量该系统中恒星的质量对于测试形成EMSP的假设很重要。我们已经与Parkes和Meerkat射电望远镜一起观察了这一脉冲星。我们的观察结果表明，该脉冲星的强度的强烈频率演变，光谱指数（$α$）为$ -3.13（2）$。与较旧的Parkes观察相比，Meerkat的敏感性在定时精度上提高了$> 10美元。结合为期8年的计时基线，它允许精确测量适当的运动和三个轨道的“遗传后”参数：Periastron的前进速率，$ \dotΩ= 0.00152（1）\，{\ rm {\ rm rm deg} \，μ$ S和$ς= 0.88（2）$。假设有一般相对论，我们获得了$ m_ {p} = 1.71（2）\，m _ {\ odot} $，用于脉冲星的质量和$ m_ {c} = 0.254（2）\，m _ {\ odot} $，用于同伴的群众；轨道倾斜度为83.2（4）度。我们发现，旋转轴相对于99％CI的轨道角动量$> 4.8 $度。尽管$ m _ {\ rm p} $的值属于EMSPS中观察到的宽范围，但$ m _ {\ rm c} $明显小于预期，允许排除几个编队假设。 $ m _ {\ rm c} $也与理想的低质量X射线二进制二进制演变方案的预期值显着不同。脉冲星的自旋轴与轨道角动量之间的假定未对准表明，创造二进制的轨道偏心的未知过程也能够改变其轨道取向，这是理解EMSP的起源的重要证据。
PSR J0955$-$6150 is a member of a class of eccentric MSP+He WD systems (eMSPs), whose binary evolution is poorly understood and believed to be different to that of traditional MSP+He WD systems. Measuring the masses of the stars in this system is important for testing hypotheses for the formation of eMSPs. We have carried out observations of this pulsar with the Parkes and MeerKAT radio telescopes. Our observations reveal a strong frequency evolution of this pulsar's intensity, with a spectral index ($α$) of $-3.13(2)$. The sensitivity of MeerKAT has resulted in a $>10$-fold improvement in the timing precision compared to older Parkes observations. Combined with the 8-year timing baseline, it has allowed precise measurements of a proper motion and three orbital "post-Keplerian" parameters: the rate of advance of periastron, $\dotω = 0.00152(1) \, {\rm deg} \, yr^{-1}$ and the orthometric Shapiro delay parameters, $h_3 = 0.89(7) \, μ$s and $ς= 0.88(2)$. Assuming general relativity, we obtain $M_{p} = 1.71(2) \, M_{\odot}$ for the mass of the pulsar and $M_{c} = 0.254(2) \, M_{\odot}$ for the mass of the companion; the orbital inclination is 83.2(4) degrees. We find that the spin axis has a misalignment relative to the orbital angular momentum of $> 4.8$ degrees at 99% CI. While the value of $M_{\rm p}$ falls within the wide range observed in eMSPs, $M_{\rm c}$ is significantly smaller than expected, allowing several formation hypotheses being ruled out. $M_{\rm c}$ is also significantly different from the expected value for an ideal low mass X-ray binary evolution scenario. The putative misalignment between the spin axis of the pulsar and the orbital angular momentum suggests that the unknown process that created the orbital eccentricity of the binary was also capable of changing its orbital orientation, an important evidence for understanding the origin of eMSPs.
