AI 中文总结
该研究基于COLIBRE宇宙学模拟，探究超新星与AGN反馈对暗晕气体含量的影响，发现其气体分数与EAGLE等模拟存在显著差异，且混合AGN反馈模型与观测约束吻合度更高。
AI 中文摘要
我们给出了星系形成的COLIBRE宇宙学模拟对暗晕气体质量分数与暗晕质量关系（$f_{\rm gas}^{200}-M_{200}$）的预测，并探究超新星反馈和活动星系核（AGN）反馈随时间对暗晕气体含量的影响。COLIBRE中的$f_{\rm gas}^{200}-M_{200}$关系呈非单调特征，在$M_{200}\backsim 10^{11.5-12}M_\bigodot$处存在峰值；低于该质量时，超新星反馈会有效将气体从矮星系暗晕中驱逐，高于该质量时，AGN反馈会有效耗尽星系群暗晕的气体。基准COLIBRE模型得到的星系群和星系团气体分数与钱德拉（Chandra）和XMM-牛顿（XMM-Newton）X射线数据的约束一致，但相对于eROSITA堆叠测量和动力学苏尼亚耶夫-泽尔多维奇（kSZ）效应推断的气体分数偏高；COLIBRE结合热反馈与喷流驱动反馈的混合AGN反馈模型，得到的气体分数更低，与eROSITA和kSZ测量结果吻合更好。COLIBRE给出的星系群和星系团气体分数低于EAGLE及其他当代模拟，与观测约束的吻合度更高。我们探究了其相对于EAGLE的改进来源，以及模拟分辨率对反馈影响的作用。结果表明，暗晕气体分数是反馈物理的灵敏探针，且在产生星系群体非常相似的模拟之间，暗晕气体分数可能存在显著差异。
英文摘要
We present predictions for the relation between the halo gas mass fraction and halo mass, $f_{\rm gas}^{200}-M_{200}$, from the COLIBRE cosmological simulations of galaxy formation, and explore how the gas content of haloes is influenced by feedback from supernovae and active galactic nuclei (AGN) over time. The $f_{\rm gas}^{200}-M_{200}$ relation in COLIBRE is non-monotonic, with a peak at $M_{200}\sim 10^{11.5-12}$~M$_\odot$. Below this mass, feedback from supernovae efficiently expels gas from the haloes of dwarf galaxies, and above it, AGN feedback efficiently depletes the haloes of galaxy groups. The fiducial COLIBRE model yields gas fractions for galaxy groups and clusters that agree with constraints from Chandra and XMM-Newton X-ray data, but which are high relative to gas fractions inferred from eROSITA stacks and measurements of the kinetic Sunyaev-Zel-dovich (kSZ) effect. COLIBRE's hybrid AGN feedback model, which combines thermal and jet-driven feedback, produces lower gas fractions in better agreement with eROSITA and kSZ measurements. COLIBRE produces lower gas fractions for groups and clusters than EAGLE and other contemporary simulations, and better agreement with observational constraints. We investigate the origin of this improvement relative to EAGLE, and how the resolution of the simulation affects the impact of feedback. Our results demonstrate that halo gas fractions are a sensitive probe of feedback physics, and that they can differ significantly between simulations that otherwise produce very similar galaxy populations.
Comments25 pages, 11 figures. Submitted to MNRAS, comments welcome
