Related papers: X-ray emission from early-type galaxies
We present the results of a search for X--ray luminous distant clusters of galaxies. We found extended X--ray emission characteristic of a cluster towards two of our candidate clusters of galaxies. They both have a luminosity in the ROSAT…
Various types of active galactic nuclei (AGN) are briefly discussed, with an emphasis on the theory of recent X-ray and $\gamma$-ray observations of the subclass, Seyfert 1 galaxies. The large radiation power from AGN is thought to…
High redshift (z >~ 1) clusters are ideal probes to study the formation and evolution of large scale structures and galaxies in the universe. A 10-m class ground based telescope, X-ray observatories (Chandra, XMM-Newton) and HST/ACS are…
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,…
The Galactic Ridge X-ray Emission (GRXE) is apparently extended X-ray emission along the Galactic Plane. The X-ray spectrum is characterized by hard continuum with a strong Fe K emission feature in the 6-7 keV band. A substantial fraction…
X-ray emission from stars has origins as diverse as the stars themselves: accretion shocks, shocks generated in wind-wind collisions, or release of magnetic energy. Although the scenarios responsible for X-ray emission are thought to be…
We present spectroscopic observations of six optical counterparts of intermediate luminosity X-ray sources (ULXs) around nearby galaxies. The spectra of the six objects show the presence of broad emission features. The identification of…
In this contribution we present a few selected examples of how the latest generation of space-based instrumentation -- NASA's Chandra X-ray Observatory and the Far-Ultraviolet Spectroscopic Explorer (FUSE) -- are finally answering old…
In this chapter we review some aspects of X-ray binaries, particularly those presenting steady jets, i.e. microquasars. Because of their proximity and similarities with active galactic nuclei (AGN), galactic jet sources are unique…
We use deep Chandra observations to measure the emissivity of the unresolved X-ray emission in the elliptical galaxy NGC 3379. After elimination of bright, low-mass X-ray binaries with luminosities >10^{36 erg/sec, we find that the…
We report the detection of hard X-ray emission (>2 keV) from a number of point sources associated with the very young massive star-forming region IRAS 19410+2336. The X-ray emission is detected from several sources located around the…
This review focuses on the X-ray emission processes of extra-galactic jets on scales resolvable by the sub arcsec resolution of the Chandra X-ray Observatory. It is divided into 4 parts. The introductory chapter reviews the classical…
Among high-redshift galaxies, aside from active galactic nuclei (AGNs), X-ray binaries (XRBs) can be significant sources of X-ray emission. XRBs play a crucial role in galaxy evolution, reflecting the stellar populations of galaxies and…
Ly$\alpha$ emission is a standard tracer of starburst galaxies at high redshift. However, a number of local Ly$\alpha$ emitters (LAEs) are X-ray sources, suggesting a possible origin of Ly$\alpha$ photons other than young, hot stars, and…
Emission from X-ray binaries (XRBs) is a major component of the total X-ray luminosity of normal galaxies, so X-ray studies of high redshift galaxies allow us to probe the formation and evolution of X-ray binaries on very long timescales.…
The launch of Chandra and XMM-Newton has led to important new findings concerning the X-ray emission from supernova remnants. These findings are a result of the high spatial resolution with which imaging spectroscopy is now possible, but…
As a byproduct of its search for the first star forming galaxies, NGST will obtain high-quality spectra for thousands of galaxies in the redshift range z = 0 - 6 and beyond. Most of the galaxies will possess strong emission-line spectra,…
We investigate models for the class of ultraluminous non-nuclear X-ray sources (ULXs) seen in a number of galaxies and probably associated with star-forming regions. Models where the X-ray emission is assumed to be isotropic run into…
Identifying gamma-ray sources in the Galaxy is hampered by their poor localization, source confusion, and the large variety of potential emitters. Neutron stars and their environment offer various ways to power gamma-ray sources: pulsed…
Planetary nebulae (PNe) were expected to be filled with hot pressurized gas driving their expansion. ROSAT hinted at the presence of diffuse X-ray emission from these hot bubbles and detected the first sources of hard X-ray emission from…