从可观测信息中推断暗物质：利用星系属性估计暗晕质量
Inferring the Dark from the Observable: Estimating Halo Masses Using Galaxy Properties
- Perimeter Institute for Theoretical Physics（Perimeter理论物理研究所）
- University of Waterloo（滑铁卢大学）
- Independent University, Bangladesh（孟加拉独立大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究利用随机森林、OLS、符号回归等方法，分析星系可观测属性与暗晕质量的相关性，发现气体质量等属性对暗晕质量估计的重要性，提出可基于星系观测量约束暗晕质量的新途径。
AI中文摘要：
星系的形成与演化与其宿主暗晕的形成演化密切相关。鉴于二者紧密关联的演化历史，星系属性应与其宿主暗晕质量存在相关性。已有研究表明，星系团暗晕中星系的恒星形成率与场暗晕中的星系存在系统性差异，这暗示宿主暗晕质量在星系演化历史中扮演重要角色。本文中，我们研究可观测星系属性（如恒星质量、恒星形成率、半恒星半径、r波段星等及颜色）与星系潜在宿主暗晕质量之间的相关性。我们利用中心星系的可观测属性探测宿主暗晕质量，同时利用卫星星系的属性估计子暗晕质量。我们采用随机森林（random forest）、普通最小二乘法（OLS）和符号回归（symbolic regression）开展分析：随机森林回归可评估不同可观测星系属性的相对重要性，而OLS与符号回归可量化这些属性与宿主暗晕质量的关系。我们的结果显示，在所有暗晕质量范围内，中心星系的气体质量通常是最重要的属性，其次是恒星质量和观测到的r波段星等。与标准的恒星-暗晕质量关系相比，加入星系颜色、星等等参数可提升宿主暗晕质量的估计精度。这些结果表明，暗晕质量对星系属性的依赖可能是多维的，为基于星系巡天中可直接观测的量寻找约束暗晕质量的简单方法开辟了途径；找到与暗晕质量相关性最强的可观测物理量，也能为未来巡天的重点观测领域提供方向。
英文摘要：
The formation and evolution of galaxies are interconnected with that of their host halos. Given this closely related evolutionary history, it should follow that galaxy properties are correlated with their host halo mass. Previous works have shown that star formation rates of galaxies in cluster halos differ systematically from those in field halos, suggesting that host halo mass plays a significant role in the history of galaxy evolution. Here, we examine the correlations between observable galaxy properties - such as stellar mass, star formation rate, half-stellar radius, $r-$band magnitude, and color - and the underlying host halo mass of galaxies. Central galaxy observables are used to probe host halo mass, while satellite galaxy properties are used to estimate subhalo mass. We perform this analysis using random forest, ordinary least squares (OLS), and symbolic regression. Random forest regression can assess the relative significance of different observable galaxy properties, while OLS and symbolic regression can quantify their relationship with the host halo mass. Our results show that gas mass is generally the most significant property in central galaxies of all halo mass ranges, followed by stellar mass and observed $r-$band magnitude. Adding parameters such as the colour and magnitude of galaxies improves host halo mass estimations compared to standard stellar-to-halo mass relations. These results show that halo mass likely has a multi-dimensional dependence on galaxy properties and open the avenue of finding a simple way to constrain halo mass based on what is directly observable in galaxy surveys. Finding the observables that have the strongest correlation with halo mass can also motivate future surveys on which areas to concentrate in detail.
