Related papers: Globular Cluster X-ray Sources
In the construction of an X-ray selected sample of galaxy clusters for cosmological studies, we have assembled a sample of 495 X-ray sources found to show extended X-ray emission in the first processing of the ROSAT All-Sky Survey. The…
X-ray imaging and spectroscopy can be used to probe the binary content of globular clusters. Binaries are thought to play a key role in the dynamical evolution of the clusters by serving as an internal source of energy which counters the…
The clusters of gamma-ray bursts are considered which are assumed to be images of the repeated gamma-ray burst (GRB) sources. It is shown, that localization of the cosmic gamma-ray burst sources (GBS) is determined by the clusters of GRBs.…
X-ray studies of nearby spiral galaxies with star formation allow us to investigate temperature and spatial distribution of the hot diffuse plasma, and to carry out individual and statistical studies of different classes of discrete sources…
We present a collection of classified X-ray sources in Globular Clusters (GCs) observed by the Chandra X-ray Observatory (CXO), including active binaries, cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries. We…
Properties of 53 globular cluster systems are investigated. Strong correlations are found between parent galaxy luminosity and both the slope of the radial density profile for clusters and the width of the cluster color (metallicity)…
X-ray observations of clusters at different redshifts are presented and compared. For the nearest cluster -- the Virgo cluster -- we show a comparison of the galaxy distribution and the distribution of the intra-cluster gas. Although the…
As part of our campaign to determine the nature of the various source populations of the low-luminosity globular cluster X-ray sources, we have obtained a Chandra X-ray Observatory ACIS-S3 image of the globular cluster NGC 6440. We detect…
We examine the spatial offsets between X-ray point sources and star clusters in three starburst galaxies. We find that the X-ray sources are preferentially located near the star clusters. Because the star clusters are very good tracers of…
The globular cluster M15 was observed on three occasions with the High Resolution Camera on board Chandra in 2001 in order to investigate the X-ray source population in the cluster centre. After subtraction of the two bright central…
Whether the X-ray luminosities of clusters of galaxies evolve has been a contentious issue for over ten years. However, the data available to address this issue have improved dramatically as cluster surveys from the ROSAT archive near…
We report on the progress of our search for serendipitous distant X-ray galaxy clusters in the ROSAT PSPC pointed observations archive. The initial aim of our work is to measure the X-ray luminosity function of clusters down to 4 x 10^-14…
We present the first study of the X-ray sources in one of the most metal-rich globular clusters in the Galaxy, NGC 6528. Using relatively deep (66 ksec) archival imaging from the Chandra X-ray Observatory, we identify 18 sources within the…
A study of the globular cluster systems of 23 brightest, or central, galaxies in 19 Abell clusters has recently been completed. This Letter presents some of the newly discovered correlations of the globular cluster specific frequency $S_N$…
Today's sensitive, high-resolution X-ray observations allow the study of populations of X-ray sources, in the luminosity range of Galactic X-ray binaries, in galaxies as distant as 20-30 Mpc. The traditional astronomical tools of…
I analyze 101 observations from the ROSAT archive to search for X-ray sources in or near 55 globular clusters. New sources are found in the cores of NGC362 (a double source), NGC6121 (marginally significant), NGC6139, and NGC6266; and…
This paper addresses the questions of what we have learned about how and when dense star clusters form, and what studies of star clusters have revealed about galaxy formation and evolution. One important observation is that globular…
We study a Chandra X-ray Observatory ACIS-S observation of the Galactic globular clusterM12. With a 26 ks exposure time, we detect 6 X-ray sources inside the half-mass radius (2.16 arcminutes) of which two are inside the core radius (0.72…
Clusters of galaxies are the most massive objects in the Universe and precise knowledge of their mass structure is important to understand the history of structure formation and constrain still unknown types of dark contents of the…
Formation of dark matter halos is sensitive to the expansion rate of the Universe and to the growth of structures under gravitational collapse. Virialization of halos heats the gaseous intra-cluster medium to high temperatures, leading to…