Related papers: High Resolution X-ray Spectroscopic Constraints on…
Recent analyses of XMM and Chandra data of the cores of X-ray bright clusters of galaxies show that modeling with a multi-phase gas in which several temperatures and densities are in equilibrium might not be appropriate. Instead, a…
Results from a large sample of hydrodynamical/N-body simulations of galaxy clusters in a LCDM cosmology are used to simulate cluster X-ray observations as expected from Chandra observations. The physical modeling of the gas includes…
The X-ray background intensity around Lick count galaxies and rich clusters of galaxies is investigated in three ROSAT energy bands. It is found that the X-ray enhancements surrounding concentrations of galaxies exhibit significantly softer…
The past two decades have witnessed the rapid growth of our knowledge of the X-ray Universe thanks to flagship X-ray space observatories like XMM-Newton and Chandra. A significant portion of discoveries would have been impossible without…
XMM-Newton observations of the outskirts of the Coma cluster of galaxies confirm the existence of a soft X-ray excess claimed previously and show it comes from warm thermal emission. Our data provide a robust estimate of its temperature…
For two decades the steady-state cooling-flow model has dominated the literature of cluster and elliptical-galaxy X-ray sources. For ten years this model has been in severe difficulty from a theoretical point of view, and it is now coming…
We study steady, homogeneous and subsonic cooling flows in poor clusters of galaxies in light of the recent proposal that radiative cooling of the intracluster gas can explain the observations of the `entropy floor' and other related X-ray…
We have analyzed X-ray spectra from six galaxy clusters which contain cooling flows: A85, A478, A1795, A2142, A2147, & A2199. The X-ray spectra were taken with the HEAO1-A2 Medium and High Energy Detectors and the Einstein Solid State…
We present an estimate of the X-ray background (XRB) spectrum from the warm-hot intergalactic medium (IGM) associated with groups and clusters of galaxies, using purely the observationally determined X-ray luminosity function (XLF) and…
We present X-ray and optical spectroscopic observations of twelve galaxy groups and clusters identified within the XMM Large-Scale Structure (LSS) survey. Groups and clusters are selected as extended X-ray sources from a 3.5 deg2 XMM image…
We present a self-consistent approach to the modeling of X-ray clusters of galaxies in a flat universe. Employing the Press and Schechter (1974) formalism to derive the mass function and relating the observable properties of clusters to…
(Abridged) We use a hydrodynamic simulation of a LambdaCDM model to predict the extragalactic X-ray background (XRB), focussing on emission from the intergalactic medium (IGM). We also include X-rays from point sources associated with…
The nature and origin of the soft X-ray excess in radio quiet AGN is still an open issue. The interpretation in terms of thermal disc emission has been challanged by the discovery of the constancy of the effective temperature despite the…
The study of soft X-ray emission of 38 X-ray selected galaxy clusters observed by ROSAT PSPC indicates that the soft excess phenomenon may be a common occurrence in galaxy clusters. Excess soft X-ray radiation, above the contribution from…
We present high-resolution X-ray spectroscopic observations of M87 with the Reflection Grating Spectrometers on XMM-Newton. We detect strong K-shell line emission from N, O, Ne, Mg, some emission from He-like Si, a fully resolved set of Fe…
X-ray emission from cool stars is an important tracer for stellar activity. The X-ray luminosity reflects different levels of activity and covers four orders of magnitude in stars of spectral types M-F. Low spectral resolution provided by…
We observed several nearby face-on spiral galaxies with the ROSAT PSPC to study their 0.1-2.0 keV diffuse emission. After the exclusion of resolved discrete sources, there is unresolved X-ray emission in all the galaxies observed. Since…
We present results of a high-resolution soft X-ray (0.2-2 keV) spectroscopic study of a sample of 69 nearby obscured Active Galactic Nuclei (AGN) observed with the Reflection Grating Spectrometer (RGS) on board XMM-Newton. This is the…
Observations of interstellar clouds that cast shadows in the soft X-ray background can be used to separate the background Galactic halo emission from the local emission due to solar wind charge exchange (SWCX) and/or the Local Bubble (LB).…
The radiative cooling time of the X-ray-emitting plasma near the center in many clusters of galaxies is shorter than the age of the cluster, but neither the expected large drop in central temperature --nor the expected mass flow towards the…