X-ray perspective on young stellar populations in objects with nuclear activity - the case of our Galactic Center-

Abstract

Although our Galactic Center harbors a black hole (Sgr A*) of a few million solar masses, it and its environments are very quiet at present. In X-rays however, the close vicinity of Sgr A* shows very unique and various phenomena mostly originated from young stellar populations. We report on the X-ray perspective on the young stellar populations which are related to our Galactic Center activities. The discussion is essentially based on the observational facts of new X-ray objects in the Galactic Center region in the $1^\circ \times 2^\circ $ area. They are;

1. Clusters of young high mass stars, which are Sgr B2, Arches, IRS 13 and Quintuplet.

2. X-ray reflections in the giant molecular clouds, such as Sgr B2, Sgr C, M0.01-0.09 and others.

3. New candidates of X-ray supernova remnants (SNRs), which are Sgr A East, G0.570-0.018 and G359.8-0.3.

4. Non-thermal Jets, Filaments and Shells, which are unique X-ray features in the GC region. These X-ray features may be closely related with each other, hence may have common origins. A unified picture is presented for the X-ray activity of our Galactic Center comparing with the X-ray spectra from other type of galaxies such as;

5. Star burst galaxy (NGC 253), low luminosity AGN (M 81) and Seyfert 2 (NGC 1068).