Premium
Sgr A East and its surroundings — a view with XMM‐Newton
Author(s) -
Sakano Masaaki,
Warwick Robert S.,
Decourchelle Anne
Publication year - 2003
Publication title -
astronomische nachrichten
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.394
H-Index - 63
eISSN - 1521-3994
pISSN - 0004-6337
DOI - 10.1002/asna.200385032
Subject(s) - physics , astrophysics , ionization , plasma , line (geometry) , abundance (ecology) , nebula , spectral line , astronomy , ion , stars , geometry , mathematics , quantum mechanics , fishery , biology
We present an X‐ray study of the Sgr A East region based on recent XMM‐Newton observations. The spectrum of Sgr A East can be represented by a two‐component thin thermal plasma model with temperatures of 1 and 4 keV, both of which have reached ionization equilibrium state. The abundance of iron is found to be higher in the central region of the nebula, with Z ≈ 3–4 solar, than in the outer area for which Z ∼ 0.5 solar. On the other hand, the abundances of other elements appear uniformly distributed with Z ∼ 1. We also detect a weak fluorescent K α line from neutral iron in the outer region of source. We discuss the nature of Sgr A East on the basis of these new X‐ray results.