Search Publications
Cosmological Evolution of the Hard X-Ray Active Galactic Nucleus Luminosity Function and the Origin of the Hard X-Ray Background
Ueda, Yoshihiro; Ohta, Kouji; Akiyama, Masayuki +1 more
We investigate the cosmological evolution of the hard X-ray luminosity function (HXLF) of active galactic nuclei (AGNs) in the 2-10 keV luminosity range of 1041.5-1046.5 ergs s-1 as a function of redshift up to 3. From a combination of surveys conducted at photon energies above 2 keV with HEAO 1, ASCA, and Chandra,…
High-Resolution X-Ray Spectroscopic Constraints on Cooling-Flow Models for Clusters of Galaxies
Kaastra, J. S.; Ferrigno, C.; Kahn, S. M. +5 more
We present high-resolution X-ray spectra of 14 putative cooling-flow clusters of galaxies obtained with the Reflection Grating Spectrometer on XMM-Newton. The clusters in the sample span a large range of temperatures and mass deposition rates. Various of these spectra exhibit line emission from O VIII, Ne X, Mg XII and XI, Al XIII and XII, Si XIV …
XMM-Newton Observations of the Perseus Cluster. I. The Temperature and Surface Brightness Structure
Böhringer, H.; Churazov, E.; Forman, W. +1 more
We present preliminary results of a XMM-Newton 50 ks observation of the Perseus Cluster that provides an unprecedented view of the central 0.5 Mpc region. The projected gas temperature declines smoothly by a factor of 2 from a maximum value of ~ 7 keV in the outer regions to just above 3 keV at the cluster center. Over this same range, the heavy-e…
X-Ray Spectroscopic Evidence for Intermediate-Mass Black Holes: Cool Accretion Disks in Two Ultraluminous X-Ray Sources
Fabian, A. C.; Miller, J. M.; Fabbiano, G. +1 more
We have analyzed an XMM-Newton observation of the nearby spiral galaxy NGC 1313, which contains two ``ultraluminous'' X-ray (ULX) sources. We measure isotropic luminosities of LX=2.0×1040 ergs s-1 and LX=6.6×1039 ergs s-1 for NGC 1313 X-1 and X-2 (0.2-10.0 keV, assuming a distance o…
A Massive X-Ray Outflow from the Quasar PDS 456
O'Brien, P. T.; Reeves, J. N.; Ward, M. J.
We report on XMM-Newton spectroscopic observations of the luminous radio-quiet quasar PDS 456. The hard X-ray spectrum of PDS 456 shows a deep absorption trough (constituting 50% of the continuum) at energies above 7 keV in the quasar rest frame, which can be attributed to a series of blueshifted K-shell absorption edges due to highly ionized iron…
X-Ray Fluctuation Power Spectral Densities of Seyfert 1 Galaxies
McHardy, I.; Nandra, K.; Vaughan, S. +11 more
By combining complementary monitoring observations spanning long, medium, and short timescales, we have constructed power spectral densities (PSDs) of six Seyfert 1 galaxies. These PSDs span >~4 orders of magnitude in temporal frequency, sampling variations on timescales ranging from tens of minutes to over a year. In at least four cases, the P…
Discovery of X-Ray Quasi-periodic Oscillations from an Ultraluminous X-Ray Source in M82: Evidence against Beaming
Mushotzky, Richard F.; Strohmayer, Tod E.
We report the discovery with the European Photon Imaging Camera CCDs on board XMM-Newton of a 54 mHz quasi-periodic oscillation (QPO) in the greater than 2 keV X-ray flux from an ultraluminous X-ray source (ULX) in the starburst galaxy M82. This is the first detection of a QPO in the X-ray flux from an extragalactic ULX and confirms that the sourc…
XMM-Newton Reveals the Quasar Outflow in PG 1115+080
Brandt, W. N.; Chartas, G.; Gallagher, S. C.
We report on an observation of the broad absorption line (BAL) quasar PG 1115+080 performed with the XMM-Newton observatory. Spectral analysis reveals the second case of a relativistic X-ray-absorbing outflow in a BAL quasar. The first case was revealed in a recent observation of APM 08279+5255 with the Chandra X-Ray Observatory. As in the case of…
X-Ray Emission from the Hot Interstellar Medium and Southwest Radio Lobe of the Nearby Radio Galaxy Centaurus A
Churazov, E.; Hardcastle, M. J.; Worrall, D. M. +5 more
We present results from two Chandra/ACIS-I observations and one XMM-Newton observation of X-ray emission from the interstellar medium (ISM) and the inner radio lobes of the nearby radio galaxy Centaurus A. The ISM has an average radial surface brightness profile that is well described by a β-model profile with index β=0.40+/-0.04 and a temperature…
A Long Look at NGC 3783 with the XMM-Newton Reflection Grating Spectrometer
Rasmussen, Andrew P.; Kahn, Steven M.; Behar, Ehud +5 more
A long 280 ks observation of the Seyfert 1 galaxy NGC 3783 with XMM-Newton is reported. We focus on the oxygen line complex between 17 and 24 Å as measured with the Reflection Grating Spectrometer. Accurate absorption column densities and emission-line fluxes are obtained. We explore several options for the geometry and physical form of the emitti…