Related papers: X-Ray Emission from Rotating Elliptical Galaxies
In some Seyfert Galaxies, the hard X-rays that produce fluorescent emission lines are thought to be generated in a hot corona that is compact and located at only a few gravitational radii above the supermassive black hole. We consider the…
We outline a scenario of galaxy formation in which the gas in galaxy-forming regions was preheated to high entropy by vigorous energy feedback associated with the formation of stars in old ellipticals and bulges and with AGN activity. Such…
The intensity of the soft X-Ray background is correlated with the distribution of galaxies. To demonstrate this, magnitude limited galaxy samples extracted from bright galaxy catalogues and the Lick counts are utilized. Significant…
(Abridged) To define a framework for the formation and evolution of the cooling cores in X-ray galaxy clusters, we study how the physical properties change as function of the cosmic time in the inner regions of a 4 keV and 8 keV galaxy…
The X-ray properties of a relaxed cluster of galaxies are determined primarily by its gravitational potential well and the entropy distribution of its intracluster gas. That entropy distribution reflects both the accretion history of the…
We present the first dynamically and thermally self-consistent calculations of fast adiabatically expanding gas flows from the Galactic disk into the halo. It is shown that in a hot plasma (T >= 10^6 K) with a high overpressure with respect…
Although only about 5 percent of the total baryonic mass in luminous elliptical galaxies is in the form of cooled interstellar gas, it is concentrated within the optical effective radius r_e where it influences the local dynamical mass. The…
We use multi-fiber spectroscopy of 12 nearby, poor groups of galaxies to address whether the groups are bound systems or chance projections of galaxies along the line-of-sight, why the members of each group have not already merged to form a…
We aim at characterizing the hot phase of the Circum-Galactic Medium in a large sample of galaxies. We stack X-ray events from the SRG/eROSITA eFEDS survey around central galaxies in the GAMA 9hr field to construct radially projected soft…
We examine the K shell emission lines produced by isothermal and simple multiphase models of the hot gas in elliptical galaxies and galaxy clusters to determine the most effective means for constraining the width of the differential…
We present {\em ROSAT} PSPC and HRI observations of the galactic wind from the starburst galaxy M82. \mbox{X-ray} emission from the wind is detected to a distance of $\sim6\kpc$ from the plane of the galaxy. Making use of the PSPC's mixture…
I review results from {\sl Chandra} observations of nearby normal edge-on galaxies (Sd to Sa types). These galaxies have a broad range of star formation rate, but none of them is dominated by a nuclear starburst. The galaxies are all in…
We examine mechanisms that may explain the luminosities and relatively low temperatures of extended X-ray emission in planetary nebulae. By building a simple flow structure for the wind from the central star during the proto, and early,…
Cooling flows are common in galaxy clusters which have cool cores. The soft X-ray emission below 1 keV from the flows is mostly absorbed by cold dusty gas within the central cooling sites. Further evidence for this process is presented here…
In this paper we use state-of-the-art N-body hydrodynamic simulations of a cosmological volume of side 100Mpc to produce many galaxy clusters simultaneously in both the standard cold dark matter (SCDM) cosmology and a cosmology with a…
We present a spectral analysis of cool and cooling gas in 45 cool-core clusters and groups of galaxies obtained from Reflection Grating Spectrometer (RGS) XMM-$Newton$ observations. The high-resolution spectra show FeXVII emission in many…
We observed a group of galaxies, HCG 57, with ASCA. Regardless that their member galaxies are dominated by spiral galaxies, we detected extended thermal X-ray emission that is attributed to hot gas with a temperature of $1.04\pm0.10$ keV.…
We report the results of an almost complete survey of the X-ray properties of Hickson's compact galaxy groups with the ROSAT PSPC. Diffuse X-ray emission is detected from 22 groups. We infer that hot intragroup gas is present in $\gtsimm…
Since the '80s the \textit{Einstein} observatory has shown the Young Stellar Objects (YSOs), emit X-rays with luminosities, in the 0.3--8 keV bandpass, up to $\rm 10^3$--$\rm 10^4$ times than the Sun and that the X-ray emission is highly…
For a sample of 9 well-studied giant ellipticals we compare the projected radial distribution of their red and blue globular cluster (GC) subpopulations with their host galaxy stellar and X-ray surface brightness profiles. We support…