Theoretical studies in gravitational wave astronomy have mostly focused on the information that can be extracted from individual detections, such as the mass of a binary system and its location in space. Here we consider how the information from multiple detections can be used to constrain astrophysical population models. This seemingly simple problem is made challenging by the high dimensionality and high degree of correlation in the parameter spaces that describe the signals, and by the complexity of the astrophysical models, which can also depend on a large number of parameters, some of which might not be directly constrained by the observations. We present a method for constraining population models using a Hierarchical Bayesian modeling approach which simultaneously infers the source parameters and population model and provides the joint probability distributions for both. We illustrate this approach by considering the constraints that can be placed on population models for galactic white dwarf binaries using a future space based gravitational wave detector. We find that a mission that is able to resolve ~5000 of the shortest period binaries will be able to constrain the population model parameters, including the chirp mass distribution and a characteristic galaxy disk radius to within a few percent. This compares favorably to existing bounds, where electromagnetic observations of stars in the galaxy constrain disk radii to within 20%.
Tests of Bayesian Model Selection Techniques for Gravitational Wave Astronomy
引力波资料的分析涉及到许多模型选择问题。最重要的例子是在仅与仪器噪声一致的数据或与仪器噪声和引力波信号一致的数据之间进行选择的检测问题。对地面引力波探测器数据的分析大多采用经典统计学方法进行，并采用Neyman-Pearson准则等方法进行模型选择。未来的空间探测器，如\emph{Laser Interferometer Space Antenna}（LISA），预计将产生丰富的数据流，包含来自数百万个源的信号。确定可解析的源的数量，以及每个源的最适当的描述构成了一个具有挑战性的模型选择问题，该问题可以在贝叶斯框架中得到最好的解决。LISA的一个重要来源是我们银河系中数百万个低质量双星系统，其中数万个是可以探测到的。不仅源的数量是未知的，而且建模波形所需的参数的数量也是未知的。例如，一个重要的可分辨星系双星的子集将显示轨道频率的演变，而一个较小的数字将有可测量的偏心率。在贝叶斯模型选择方法中，需要计算竞争模型之间的贝叶斯因子。在这里，我们将探讨各种方法来计算贝叶斯因子的背景下，确定银河双星可测量的频率演变。探索的方法包括反向跳马尔可夫链蒙特卡罗（RJMCMC）算法，萨维奇-迪基密度比，施瓦茨-贝叶斯信息准则（BIC），和拉普拉斯近似模型的证据。我们发现所有的方法之间的良好协议。
Analyzing GW231109_235456 and understanding its potential implications for population studies, nuclear physics, and multi-messenger astronomy
Utrecht University（乌得勒支大学）；Nikhef（尼黑国家核与亚原子物理研究所）；Universität Potsdam（波茨坦大学）；Max Planck Institute for Gravitational Physics (Albert Einstein Institute)（马克斯·普朗克引力物理研究所（爱因斯坦研究所））
Expanding Horizons - Transforming Astronomy in the 2040s Time-Domain Multi-Messenger Astronomy in the 2040s: EM Follow-up of LGWA Sources
European Southern Observatory（欧洲南方天文台）；INAF-Observatory of Rome（意大利国家天体物理研究所罗马天文台）；INAF-Observatory of Padova（意大利国家天体物理研究所帕多瓦天文台）；INGV-Catania（意大利国家地球物理学和火山学研究院卡塔尼亚分部）；INAF-Observatory of Brera（意大利国家天体物理研究所布雷拉天文台）；INAF-Observatory of Abruzzo（意大利国家天体物理研究所阿布鲁佐天文台）；INAF-Bologna（意大利国家天体物理研究所博洛尼亚分部）；Gran Sasso Science Institute（格兰萨索科学研究所）；INGV-Bologna（意大利国家地球物理学和火山学研究院博洛尼亚分部）；University of Camerino（卡梅里诺大学）
