13.  Xu, Haiguang  (徐海光)

     Physics Building 1206

Department of Physics,

Shanghai Jiao Tong University

800 Dongchuan Road, Minhang,

Shanghai 200240, PRC

E-mail: hgxu@sjtu.edu.cn

Tel & Fax: +86-21-5474-2055

Title of talk: 2D metal distribution in the hot gas of the compact group of galaxies HCG 62

Abstract: We present the X-ray imaging spectroscopic study of the compact group of galaxies HCG 62 (z=0,0137) with the high-resolution Chandra ACIS data. By using the Centroidal Voronoi Tessellation arithmetic, we obtain the two-dimensional distributions of the gas temperature and iron-dominated metal abundance. We find that the X-ray emitting gas around the central galaxy is roughly distributed in a symmetric pattern. The gas temperature is about 0.7 keV at the center and then gradually increases with radius to about 1.2 keV in the outermost region of the group. At about 35 kpc to the group center, there is an arc structure where the metal abundance is remarkably high at the 90% confidence level. The arc extends clockwise from the west of the central galaxy to the south and is about 20 kpc in width. The average gas temperature and abundance of this arc region are about 1.30 keV and 0.56 solar, respectively, which are higher than those of the rest regions. Also, the metal abundance shows clear spatial variations up to about 0.8 solar in the metal-rich arc, with its total iron mass estimated to be of the order 1e7 solar mass. It is hard to interpret the origin of this abundance arc in terms of the resonant scatterings due to its asymmetry, nor is it formed by tidal or ram pressure stripping. More possibly, it is caused by massive gas outflows triggered by starbursts and/or merger events in history.

 14．Xue, She Sheng（薛社生）

      ICRAnet

     Piazzale della Repubblica,

     10 - 65100 Pescara,

     Italy

      Email: xue@icra.it

    Title of talk: TBA

    Abstract: