发表机构
University of Hawai’i; Texas A&M University（夏威夷大学; 德州农工大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用Auriga模拟检验银河系质量暗晕的相空间分布，发现$f(E,L)$近似有效但非完全精确，残差源于非球对称效应，角动量依赖在统计上更受青睐。
AI 中文摘要
我们研究了Auriga模拟中银河系质量暗晕的暗物质相空间分布，考虑了流体动力学和仅暗物质两种运行。在球对称平均势中，我们检验了粗粒化分布函数能否近似为运动积分$E$和$L$的函数。我们发现$f(E,L)$对模拟暗晕提供了有用的描述：尽管偏离这一形式在统计上显著，但径向壳层之间的中位分数残差通常$\lesssim 15\\%$，90百分位残差约为百分之几十。仅能量近似$f(E)$给出相似的中位残差，但在$\chi^2$检验中系统性地处于劣势，表明角动量依赖在统计上更受青睐。最终我们发现，无论是$f(E)$还是$f(E,L)$都不能高精度地完全描述粒子数据。剩余的残差可能反映了对球对称平衡的偏离，包括各向异性、三轴性、次结构和重子效应。
英文摘要
We study the dark-matter phase space distribution of Milky Way-mass halos in the Auriga simulations, considering both hydrodynamic and dark-matter-only runs. In a spherically averaged potential, we test whether the coarse-grained distribution function can be approximated as a function of the integrals of motion $E$ and $L$. We find that $f(E,L)$ provides a useful description of the simulated halos: although the deviations from this form are formally statistically significant, the median fractional residuals between radial shells are typically $\lesssim 15\%$, with 90th-percentile residuals of order tens of percent. An energy-only approximation, $f(E)$, gives similar median residuals but is systematically disfavored by $χ^2$ tests, indicating that angular momentum dependence is statistically preferred. Ultimately we find that neither $f(E)$ nor $f(E,L)$ fully describes the particle data at high precision. The remaining residuals likely reflect departures from spherical equilibrium, including anisotropy, triaxiality, substructure, and baryonic effects.
Comments11 pages, 4 figures, PDFLaTeX
