Stellar halos of bright central galaxies,Astronomy & Astrophysics

当前位置： X-MOL 学术 › Astron. Astrophys. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Stellar halos of bright central galaxies
Astronomy & Astrophysics ( IF 5.4 ) Pub Date : 2024-12-16 , DOI: 10.1051/0004-6361/202452741
Emanuele Contini, Marilena Spavone, Rossella Ragusa, Enrichetta Iodice, Sukyoung K. Yi

Aims. We present theoretical predictions and extrapolations from observed data of the stellar halos surrounding central group and cluster galaxies, and the transition radius between them and the intracluster or diffuse light.Methods. Leveraging the state-of-the-art semi-analytic model of galaxy formation, FEGA (Formation and Evolution of GAlaxies), applied to two dark matter-only cosmological simulations, we derived both the stellar halo mass and its radius. Using theoretical assumptions about the diffuse light distribution and halo concentration, we extrapolated the same information for observed data from the VEGAS survey.Results. Our model, supported by observational data and independent simulation results, predicts an increasing transition radius with halo mass, a constant stellar halo-to-intracluster light ratio, and a stable stellar halo mass fraction with increasing halo mass. Specifically, we find that the transition radius between the stellar halo and the diffuse light ranges from 20 to 250 kpc, from Milky Way-like halos to large clusters, while the stellar halo mass comprises only a small fraction, between 7% and 18%, of the total stellar mass within the virial radius.Conclusions. These results support the idea that the stellar halo can be viewed as a transition region between the stars bound to a galaxy and those belonging to the intracluster light and are consistent with recent observations and theoretical predictions.

中文翻译：

明亮中央星系的恒星晕

目标。我们提出了对中心星系群和星系团周围的恒星晕的观测数据进行理论预测和推断，以及它们与星系团内或漫射光之间的过渡半径。方法。利用最先进的星系形成半分析模型 FEGA（GAlaxies 的形成和演化），应用于两个纯暗物质的宇宙学模拟，我们推导出了恒星晕质量及其半径。使用关于漫射光分布和光晕浓度的理论假设，我们为 VEGAS 调查的观测数据推断出相同的信息。结果。我们的模型得到了观测数据和独立模拟结果的支持，预测了随着光晕质量的增加而增加的过渡半径，恒定的恒星光晕与星系团内光比，以及随着光晕质量的增加而稳定的恒星光晕质量分数。具体来说，我们发现恒星晕和漫射光之间的过渡半径范围为 20 到 250 kpc，从银河系状晕到大星团，而恒星晕质量仅占维里半径内恒星总质量的一小部分，在 7% 到 18% 之间。结论。这些结果支持了这样一种观点，即恒星晕可以被视为与星系绑定的恒星与属于星系内光的恒星之间的过渡区域，这与最近的观测和理论预测一致。