Chandra View on Sgr A East

Maeda, Y.1; Baganoff, F. K.2; Feigelson, E. D.3; Morris, M.4; Bautz, M. W.2; Brandt, W. N.3; Burrows, D. N.3; Doty, J. P.2; Garmire, G. P.3; Pravdo, S. H.5; Ricker, G. R.2; Townsley, L. K.3; Park, S.3; Itoh, K.1

1 nstitute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan
2 Massachusetts Institute of Technology, Center for Space Research, 77 Massachusetts Avenue, Cambridge, MA 02139-4307
3 Department of Astronomy and Astrophysics, 525 Davey Laboratory, Pennsylvania State University, University Park, PA 16802-6305
4 Division of Astronomy, Box 951562, UCLA, Los Angeles, CA 90095-1562. 5 Jet Propulsion Laboratory, MS 306-438, 4800 Oak Grove Drive, Pasadena, CA 91109

E-mail contact: ymaeda@astro.isas.ac.jp

See ApJ, 570, 671 (2002)

We report on the X-ray emission from the shell-like, non-thermal radio source Sgr A East located in the inner few parsecs of the Galaxy based on observations made with the ACIS detector on board the Chandra X-ray Observatory. This is the first time Sgr A East has been clearly resolved from other complex structures in the region. The X-ray emitting region is concentrated within the central 2 pc of the larger radio shell. The spectrum shows strong Kalpha; lines from highly ionized ions of S, Ar, Ca, and Fe. The plasma appears to be rich in heavy elements, over-abundant by roughly a factor of four with respect to solar abundances, and shows a spatial gradient of elemental abundance: the spatial distribution of iron is more compact than that of the lighter elements. The gas mass and elemental abundance of the X-ray emission support the long-standing hypothesis that Sgr A East is a supernova remnant (SNR), The relation between Sgr A East and the supermassive blackhole Sgr A* is discussed.