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Partial Covering Interpretation of the X-Ray Spectrum of the NLS1 1H 0707-495

Ueda, Yoshihiro; Tanaka, Yasuo; Gallo, Luigi +2 more

The X-ray spectrum of 1H 0707 - 495 obtained with XMM-Newton showing a deep flux drop at ∼ 7 keV (Boller et al. 2002) is studied based on the partial covering concept. The previously inferred extreme iron overabundance can be reduced down to ∼ 3× solar if the hard component gradually steepens at high energies. The spectral shape supports that 1H 0…

Probing Warm-Hot Intergalactic Medium Associated with the Virgo Cluster Using an Oxygen Absorption Line

Kelley, Richard L.; Kilbourne, Caroline A.; Ohashi, Takaya +8 more

To detect a warm-hot intergalactic medium (WHIM) associated with the large-scale structure of the universe, we observed a quasar behind the Virgo cluster with XMM-Newton. With 54ks exposure, we marginally detected an O VIII Kα absorption line at 650.9^+0.8_-1.9eV in the RGS spectra, with a statistical confidence of 96.4%. The o…

Locating the Warm--Hot Intergalactic Medium in the Simulated Local Universe

Ishida, Manabu; Dolag, Klaus; Ohashi, Takaya +11 more

We present an analysis of mock spectral observations of warm-hot intergalactic medium (WHIM) using a constrained simulation of the local universe. The simulated map of oxygen emission lines from local WHIM well reproduces the observed structures traced by galaxies in the real local universe. We further attempt to perform mock observation of the ou…

XMM-Newton Observations of G32.45+0.1 and G38.55+0.0: Diffuse Hard X-Ray Sources Found by the ASCA Galactic Plane Survey

Ueno, Masaru; Yamaguchi, Hiroya; Koyama, Katsuji +2 more

We report on XMM-Newton observations of G32.45+0.1 and G38.55+0.0. These were discovered as diffuse hard X-ray sources by the ASCA Galactic Plane Survey, but the limited spatial resolution of ASCA could not conclude whether these are truly diffuse or a group of unresolved point-sources. XMM-Newton, with higher spatial resolution than ASCA, confirm…

Discovery of a Peculiar Pulsar in the Small Magellanic Cloud

Ueno, Masaru; Yamaguchi, Hiroya; Takagi, Shin-Ichiro +2 more

We report on a peculiar X-ray binary pulsar, IKT 1 = RX J0047.3 - 7312, observed with XMM-Newton in 2000 October. The X-ray spectrum is described by a two-component spectrum. The hard component has a broken power-law with respective photon indices of 0.2 and 1.8, below and above the break energy at 5.8keV. The soft component can be modeled by a bl…