论文标题
新的恒星大众代理Subhalo丰度匹配
A New Stellar Mass Proxy for Subhalo Abundance Matching
论文作者
论文摘要
Subhalo丰度匹配（Sham）在提高我们对星系如何填充其宿主暗物质光环的理解方面发挥了重要作用。从本质上讲，假框架是找到与星系属性（例如恒星质量）属性相关的暗物质光环属性。 Halo/subhalo在其一生中曾经达到的最大圆速度的峰值（$ v _ {\ rm max} $），$ v _ {\ rm peak} $一直是假手术的流行选择。 Tonnesen＆Ostriker（2021）的最新研究表明，将当今$ v _ {\ rm max} $和光晕暗物质质量的峰值结合的数量$ ϕ $在预测恒星质量方面的性能要比$ v _ {\ rm peacs} $更好。受其方法的启发，在这项工作中，我们发现可以通过数量$ψ_5$来实现进一步的改进，该数量结合了$ v _ {\ rm max} $ halo/subhalo的第90个百分位数，而暗物质时间变量的第60个百分位数。基于模拟Illustristng300的测试表明，我们的新假方案只有三个免费参数可以将出色的质量预测和质量依赖的聚类提高15％和16％，从$ Z = 0-2 $上升。
Subhalo abundance matching (SHAM) has played an important role in improving our understanding of how galaxies populate their host dark matter halos. In essence, the SHAM framework is to find a dark matter halo property that best correlates with an attribute of galaxies, such as stellar mass. The peak value of the maximum circular velocity ($V_{\rm max}$) a halo/subhalo has ever attained throughout its lifetime, $V_{\rm peak}$, has been a popular choice for SHAM. A recent study by Tonnesen & Ostriker (2021) suggested that quantity $ϕ$, which combines the present-day $V_{\rm max}$ and the peak value of halo dark matter mass, performs better in predicting stellar mass than $V_{\rm peak}$. Inspired by their approach, in this work, we find that further improvement can be achieved by a quantity $ψ_5$ that combines the 90th percentile of $V_{\rm max}$ a halo/subhalo has ever achieved with the 60th percentile of the dark matter halo time variation rate. Tests based on the simulation IllustrisTNG300 show that our new SHAM scheme, with just three free parameters, can improve the stellar mass prediction and mass-dependent clustering by 15% and 16% from $ϕ$, respectively, over the redshift range $z=0-2$.
