NGC 3079: X-ray emission from the nuclear super-bubble and halo

We report the results of the spatial and spectral analysis of the ROSAT HRI and PSPC observations of the edge-on spiral galaxy NGC 3079. We detected s everal sources in the field of NGC 3079 with both PSPC and HRI, and complex emission from the inner 5' around NGC 3079. We have identified possible co unterparts for several of the sources outside NGC 3079 by comparison with o ptical plates and catalogues. The X-ray emission from NGC 3079 has a L-X 3 x 10(40) erg s(-1) and can be resolved into the following three components: Extended emission in the innermost region, with L-X = 1 x 10(40) erg s(-1), coincident with the super-bubble seen in optical images. The active nucleu s may contribute to the emission as a point source. Emission from the disk of the galaxy, with L-X = 7 x 10(39) erg s(-1), that can be partly resolved by the HRI in 3 point-like sources with luminositie s of similar to 6 x 10(38) erg s(-1) each. Very soft X-shaped emission from the halo, with Lx 6 x 10(39) erg s(-1), ex tending to a diameter of 27 kpc. The X-ray luminosity of NGC 3079 is higher by a factor of 10 compared to ot her galaxies of similar optical luminosity and we argue that this may be ca used by the presence of an AGN rather than by starburst activity. The influ ence of the AGN on the companion galaxies in the NGC 3079 group are discuss ed.