发表机构
Peking University; Kavli Institute for Astronomy and Astrophysics, Peking University; Tsung-Dao Lee Institute, and Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai Jiao Tong University; Department of Astronomy, School of Physics and Astronomy, Shanghai Jiao Tong University（北京大学; 北京大学科维理天文与天体物理研究所; 上海交大泛亚量子科学中心及粒子物理与宇宙学上海市重点实验室，上海交通大学; 上海交通大学物理与天文学院天文学系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究结合MaNGA、ALFALFA和SDSS群数据重建星系晕质量分布，发现大质量暗晕内暗物质含量显著低于IllustrisTNG和EAGLE模拟预测，暗示重子加热效应被低估。
AI 中文摘要
星系晕的质量轮廓编码了重子如何重塑暗物质分布的信息，然而在整个径向范围内的直接观测约束仍然稀缺。在此，我们结合来自MaNGA的恒星运动学、来自ALFALFA的H I动力学测量以及独立校准的SDSS群暗晕质量，在近两个数量级的半径范围内统计重建中央星系的质量分布。我们证明，仅凭H I数据无法提供可靠的暗晕总质量估计，因此需要独立的基于群暗晕的质量标度。与IllustrisTNG和EAGLE模拟相比，低质量暗晕的观测轮廓大体一致；相反，在固定总暗晕质量下，大质量观测暗晕在H I半径处表现出系统性地更低的动力学质量、更低的内暗物质质量以及更低的中心暗物质占比（以群体离散度为单位约4σ的差异）。在扣除重子贡献后，推断出的暗物质轮廓仍与NFW形式大体一致，但有效浓度低于对大质量暗晕的预测。这些结果表明，大质量暗晕的内暗物质含量比当前流体动力学模拟所预测的减少得更显著，这可能是由于大质量系统中长期的重子暗晕加热所致。
英文摘要
The mass profiles of galaxy halos encode how baryons reshape dark matter distribution, yet direct observational constraints across the full radial range remain scarce. Here we combine stellar kinematics from MaNGA, H I dynamical measurements from ALFALFA, and independently calibrated halo masses of SDSS groups to statistically reconstruct the mass distribution of central galaxies over nearly two orders of magnitude in radius. We demonstrate that H I data alone do not provide reliable total halo mass estimates, necessitating an independent group-based halo-mass scale. Compared to the IllustrisTNG and EAGLE simulations, the observational profiles of low-mass halos are broadly consistent; in contrast, massive observed halos exhibit systematically lower dynamical masses at the H I radius, lower inner dark-matter masses, and lower central dark-matter fractions (about 4$σ$ difference in units of population scatter) at fixed total halo mass. After subtracting baryonic contributions, the inferred dark-matter profiles remain broadly consistent with an NFW form, but with lower effective concentrations than predicted for massive halos. These results suggest that the inner dark-matter content of massive halos has been reduced more significantly than predicted by current hydrodynamical simulations, plausibly due to long-term baryonic halo heating in massive systems.
Comments25 pages, 3+3 figures, submitted
