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The M81 group member dwarf galaxy IC 2574 hosts a supergiant shell of current and recent star-formation activity surrounding a 1000 x 500 pc hole in the ambient Hi gas distribution. Chandra X-ray Observatory imaging observations reveal a luminous, L_x ~ 6.5 x 10^{38} erg/s in the 0.3 - 8.0 keV band, point-like source within the hole but offset from its center and fainter diffuse emission extending throughout and beyond the hole. The star formation history at the location of the point source indicates a burst of star formation beginning ~25 Myr ago and currently weakening and there is a young nearby star cluster, at least 5 Myr old, bracketing the likely age of the X-ray source at between 5 and ~25 Myr. The source is thus likely a bright high-mass X-ray binary --- either a neutron star or black hole accreting from an early B star undergoing thermal-timescale mass transfer through Roche lobe overflow. The properties of the residual diffuse X-ray emission are consistent with those expected from hot gas associated with the recent star-formation activity in the region.
In young starburst galaxies, the X-ray population is expected to be dominated by the relics of the most massive and short-lived stars, black-hole and neutron-star high mass X-ray binaries (XRBs). In the closest such galaxy, IC 10, we have made a mult
The main results from a deep X-ray observation of M82 are summarised: spatially-dependent chemical abundances, temperature structure of the gas, charge-exchange emission lines in the spectrum. We also present an update of the chemical bundances, based on a more refined extraction of spectra.
The past decade has seen a large progress in the X-ray investigation of early-type galaxies of the local universe, and first attempts have been made to reach redshifts z>0 for these objects, thanks to the high angular resolution and sensitivity of th
Supergiant Fast X-ray Transients (SFXTs) are a new class of High Mass X-ray Binaries, discovered by the INTEGRAL satellite, which display flares lasting from minutes to hours, with peak luminosity of 1E36-1E37 erg/s. Outside the bright outbursts, the
We present an optical and infrared (IR) study of IC 10 X-2, a high-mass X-ray binary in the galaxy IC 10. Previous optical and X-ray studies suggest X-2 is a Supergiant Fast X-ray Transient: a large-amplitude (factor of $sim$ 100), short-duration (ho