摘要
By analyzing the azimuthal variations of total gravitating mass profiles in the central 300 h^-1 71 kpc regions of four galaxy clusters with Chandra data, we find that the azimuthally-averaged mass profiles may have been systematically underestimated by 16^＋9 -8% at lσ significance in the 50-100 h^-1 71 kpc regions, probably due to the prevailing existence of 2-D hot gas substructures in 100-300h^-1 71 kpc. The mass biases become negligible（-7＋11 _9＋ %） at 〉 150 h^-1 71 kpc. We confirm the results that the gas temperature maps can be used to probe the departure from hydrostatic equilibrium and help quantify the systematic biases in X-ray mass measurements in the central regions of clusters.
By analyzing the azimuthal variations of total gravitating mass profiles in the central 300 h^-1 71 kpc regions of four galaxy clusters with Chandra data, we find that the azimuthally-averaged mass profiles may have been systematically underestimated by 16^＋9 -8% at lσ significance in the 50-100 h^-1 71 kpc regions, probably due to the prevailing existence of 2-D hot gas substructures in 100-300h^-1 71 kpc. The mass biases become negligible（-7＋11 _9＋ %） at 〉 150 h^-1 71 kpc. We confirm the results that the gas temperature maps can be used to probe the departure from hydrostatic equilibrium and help quantify the systematic biases in X-ray mass measurements in the central regions of clusters.
基金
supported by National Natural Science Foundation of China(Grant Nos.10673008,10878001and10973010)
the Ministry of Science and Technology of China(Grant No.2009CB824900/2009CB24904)
the Ministry of Education of China(the NCET Program)
