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We report on the detection of ultra-fast outflows in the Seyfert~1 galaxy Mrk 590. These outflows are identified through highly blue-shifted absorption lines of OVIII and NeIX in the medium energy grating spectrum and SiXIC and MgXII in the high ener gy grating spectrum on board Chandra X-ray observatory. Our best fit photoionization model requires two absorber components at outflow velocities of 0.176c and 0.0738c and a third tentative component at 0.0867c. The components at 0.0738c and 0.0867c have high ionization parameter and high column density, similar to other ultra-fast outflows detected at low resolution by Tombesi et al. These outflows carry sufficient mass and energy to provide effective feedback proposed by theoretical models. The component at 0.176c, on the other hand, has low ionization parameter and low column density, similar to those detected by Gupta et al. in Ark~564. These absorbers occupy a different locus on the velocity vs. ionization parameter plane and have opened up a new parameter space of AGN outflows. The presence of ultra-fast outflows in moderate luminosity AGNs poses a challenge to models of AGN outflows.
Suzaku performed observations of 3 regions in and around the Shapley supercluster: a region located between A3558 and A3556, at ~0.9 times the virial radii of both clusters, and two other regions at 1{deg}and 4{deg}away from the first pointing. The 4 {deg}-offset observation was used to evaluate the Galactic foreground emission. We did not detect significant redshifted Oxygen emission lines (O VII and O VIII) in the spectra of all three pointings, after subtracting the contribution of foreground and background emission. An upper limit for the redshifted O VIII Ka line intensity of the warm-hot intergalactic medium (WHIM) is 1.5 times 10^-7 photons s^-1 cm^-2 arcmin^-2, which corresponds to an overdensity of ~380 (Z/0.1 Z_solar)^{-1/2} (L/3 Mpc)^{-1/2}, assuming T=3times10^6 K. We found excess continuum emission in the 1{deg}-offset and on-filament regions, represented by thermal models with kT ~1 keV and ~2 keV, respectively. The redshifts of both 0 and that of the supercluster (0.048) are consistent with the observed spectra. The ~1 keV emission can be also fitted with Ne-rich Galactic (zero redshift) thin thermal emission. Radial intensity profile of 2 keV component suggests contribution from A3558 and A3556, but with significant steepening of the intensity slope in the outer region of A3558. Finally, we summarized the previous Suzaku search for the WHIM and discussed the feasibility of constraining the WHIM. An overdensity of < 400 can be detectable using O VII and O VIII emission lines in a range of 1.4times10^6 K < T < 5times10^6 K or a continuum emission in a relatively high temperature range T > 5times10^6 K with the Suzaku XIS. The non detection with Suzaku suggests that typical line-of-sight average overdensity is < 400.
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