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We present the analysis of an XMM-Newton observation of the M17 nebula. The X-ray point source population consists of massive O-type stars and a population of probable low-mass pre-main sequence stars. CEN1a,b and OI352, the X-ray brightest O-type stars in M17, display hard spectra (kT of 3.8 and 2.6 keV) consistent with a colliding wind origin in binary/multiple systems. We show that the strong interstellar reddening towards the O-type stars of M17 yields huge uncertainties on their Lx/Lbol values. The low-mass pre-main sequence stars exhibit hard spectra resulting from a combination of high plasma temperatures and very large interstellar absorption. We find evidence for considerable long term (months to years) variability of these sources. M17 is one of the few star formation complexes in our Galaxy producing diffuse X-ray emission. We analyze the spectrum of this emission and compare it with previous studies. Finally, we discuss the Optical Monitor UV data obtained simultaneously with the X-ray images. We find very little correspondence between the UV and X-ray sources, indicating that the majority of the UV sources are foreground stars, whilst the bulk of the X-ray sources are deeply embedded in the M17 complex.
We report on two XMM-Newton observations of the bright narrow-line Seyfert 1 galaxy Ark 564 taken one year apart (2000 June and 2001 June). The 0.6-10 keV continuum is well described by a soft blackbody component (kT~140-150 eV) plus a steep power la
We present the first high signal-to-noise XMM-Newton observations of the broad-line radio galaxy 3C 411. After fitting various spectral models, an absorbed double power-law continuum and a blurred relativistic disk reflection model (kdblur) are found
While theory and simulations indicate that galaxy mergers play an important role in the cosmological evolution of accreting black holes and their host galaxies, samples of Active Galactic Nuclei (AGN) in galaxies at close separations are still small.
We report on the nuclear X-ray properties of the radio galaxy NGC 6251 observed with XMM-Newton. NGC 6251 is a well-known radio galaxy with intermediate FRI/II radio properties. It is optically classified as a Seyfert 2 and hosts a supermassive black
The distribution of hot interstellar medium in early-type galaxies bears the imprint of the various astrophysical processes it underwent during its evolution. The X-ray observations of these galaxies have identified various structural features relate