论文标题

贝叶斯对2016年Vela Pulsar中惯性超级流体时刻的估计值

Bayesian estimate of the superfluid moments of inertia from the 2016 glitch in the Vela pulsar

论文作者

Montoli, Alessandro, Antonelli, Marco, Magistrelli, Fabio, Pizzochero, Pierre

论文摘要

Vela Pulsar中第一个脉冲到脉冲小故障的观察为中子星的内部动力学打开了一个新窗口。我们通过在通用初始条件下求解脉冲星故障的最小三组分模型。目的是使用该解决方案通过采用贝叶斯方法来拟合2016 Vela故障的数据,并获得模型的物理参数和观察参数的概率分布,例如小故障的上升时间和放松时间表。拟合是通过贝叶斯推断实现的。由于故障时间附近的定时残差存在增加,因此将额外的磁层成分添加到三组分模型中以处理这种现象。在模型的参数上设置了物理合理的,非信息性的先验,以便可以将后验分布与从微物理计算获得的信息进行比较。通过考虑一个在惯性分数时刻收紧先验的模型,并通过贝叶斯模型选择将其与原始模型进行比较,我们研究了甲壳限制的超氟化储层的可能性。我们在超级流体成分的惯性分数,耦合参数和组件之间的初始速度滞后时获得了后验分布。对推断后验的分析还证实了该故障中存在一个过冲,并将上限为$ \ sim 6 \,$ s,$ s,$ s,在小故障升高时间表上。在惯性分数的时刻,这两个模型之间的比较似乎表明需要核心参与小故障现象,而不管夹带耦合的不确定强度如何。

The observation of the first pulse-to-pulse glitch in the Vela pulsar opens a new window on the internal dynamics of neutron stars. We study the minimal three-component model for pulsar glitches by solving it with generic initial conditions. The purpose is to use this solution to fit the data of the 2016 Vela glitch by employing a Bayesian approach and to obtain a probability distribution for the physical parameters of the model and for observational parameters, such as the glitch rise time and the relaxation timescale. The fit is achieved through Bayesian inference. Due to the presence of an increase in the timing residuals near the glitch time, an extra magnetospheric component was added to the three-component model to deal with this phenomenon. A physically reasonable, non-informative prior was set on the parameters of the model, so that the posterior distribution could be compared with information obtained from microphysical calculations. By considering a model with a tightened prior on the moment of inertia fractions and by comparing it with the original model by means of Bayesian model selection, we studied the possibility of a crust-limited superfluid reservoir. We obtained the posterior distribution for the moment of inertia fractions of the superfluid components, the coupling parameters, and the initial velocity lags between the components. An analysis of the inferred posterior also confirmed the presence of an overshoot in that glitch and set an upper limit of $\sim 6\,$s on the glitch rise timescale. The comparison between the two models with different priors on the moment of inertia fractions appears to indicate a need for a core participation in the glitch phenomenon, regardless of the uncertain strength of the entrainment coupling.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源