2026/07/20 by Xiaoxia Zhang, Taotao Fang, Shulan Yan +2
#astro-ph.GA
The relationship between supermassive black holes and the multiphase circumgalactic medium is central to understanding the co-evolution of galaxies and their central black holes. We investigate this relationship using the IllustrisTNG100 simulation with a sample of 5089 central galaxies at z=0, measuring the partial correlation between central black hole mass and the mass of cold (T < 104K), cool (104 ≤ T < 105K), warm (105 ≤ T < 106K), and hot (T ≥ 106K) gas within 0.03R200, 0.15R200, and R200, after accounting for stellar and dark matter halo mass. We find that after removing these confounding factors, black hole mass shows a significant negative partial correlation (ρ≈ -0.37) with cold gas within R200 and 0.15R200, whereas warm and hot gas exhibit no substantial intrinsic correlation. The residual plane reveals a threshold pattern: galaxies with over-massive black holes show systematically reduced cold gas, consistent with the cumulative impact of AGN feedback. The anti-correlation persists across environments with a weak trend in local density, and varies with galaxy type (star-forming, green valley, and quenched). These results provide a quantitative multiphase diagnostic of AGN feedback in TNG and support a picture in which feedback progressively removes cold gas, offering testable predictions for future multiwavelength surveys.