论文标题
靶向各向异性引力波背景的贝叶斯参数估计
Bayesian parameter estimation for targeted anisotropic gravitational-wave background
论文作者
论文摘要
传统的重力背景的扩展来源已在球形谐波底座上进行了常规搜索。在先前的观察过程中，地面引力波检测器（例如Ligo和处女座）在角度功率谱$ c_ \ ell $上产生了约束，但它缺乏估计模型参数的能力。在本文中，我们介绍了另一种贝叶斯形式主义，以搜索这种随时分布在天空上具有特殊分布的随机信号。这种方法提供了模型参数的贝叶斯后方，还可以在不同的信号模型之间进行选择测试。尽管常规分析固定了最高的角度量表\ textit {a先验}，但在这里我们显示了一种基于贝叶斯因子的截止量表，以确定截止量表，这取决于观察到的信号的幅度和角度尺度。此外，我们为Milli-Second Pulsars的种群分析了Ligo和处女座的第三次观测，并获得了信号振幅的95％约束，$ε<2.7 \ times 10^{ - 8} $。
Extended sources of the stochastic gravitational backgrounds have been conventionally searched on the spherical harmonics bases. The analysis during the previous observing runs by the ground-based gravitational wave detectors, such LIGO and Virgo, have yielded the constraints on the angular power spectrum $C_\ell$, yet it lacks the capability of estimating model parameters. In this paper, we introduce an alternative Bayesian formalism to search for such stochastic signals with a particular distribution of anisotropies on the sky. This approach provides a Bayesian posterior of model parameters and also enables selection tests among different signal models. While the conventional analysis fixes the highest angular scale \textit{a priori}, here we show a more systematic and quantitative way to determine the cut-off scale based on a Bayes factor, which depends on the amplitude and the angular scale of observed signals. Also, we analyze the third observing runs of LIGO and Virgo for the population of milli-second pulsars and obtain the 95 % constrains of the signal amplitude, $ε< 2.7\times 10^{-8}$.
