Star-burst galaxy M83 observed from ASCA

Combined spectral and spatial analyses of the central region of the nearby spiral galaxy M83 shows the presence of two different emission components. One component has a spatial size of 2.'7, as defined by the rms radius of the emission region, and has an emission temperature of about 5 keV when it is approximated with a thermal-bremsstrahlung model. The other component has a much smaller radius with an upper limit of 1.'0 rms radius, and has a lower emission temperature of about 0.4 keV. The X-ray luminosities of the two components are, respectively, 2.1 x 10(39) erg s(-1) (soft component) and 4.8 x 10(39) erg s(-1) (hard component) in the 0.5-10 keV band (for the distance of 3.75 Mpc). The soft, lower-temperature component is consistent to be emission from the hot gas originating from the star-burst activity in the galaxy. On the other hand, the hard component is consistent with being a collection of binary X-ray sources in the bulge region.