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X-Ray Spectral Properties of Low-Mass X-Ray Binaries in Nearby Galaxies
We have investigated the X-ray spectral properties of a collection of low-mass X-ray binaries (LMXBs) within a sample of 15 nearby early-type galaxies using proprietary and archival data from the
X-Ray Evidence for the Interaction of the Giant Elliptical Galaxy NGC 4472 with its Virgo Cluster Environment
We analyze X-ray spatial and spectral data on the giant elliptical galaxy NGC 4472, the brightest galaxy in the Virgo cluster. The X-ray contours of NGC 4472 are elongated in the northeast-southwest
Classifying X-Ray Sources in External Galaxies from X-Ray Colors
The X-ray populations of Local Group galaxies have been classified in detail by Einstein, ROSAT, and ASCA, revealing a mix of binaries, supernova remnants (SNRs), and H II regions. However, these
A Chandra ACIS S3 observation of the X-ray faint elliptical galaxy NGC 4697 resolves much of the X-ray emission (61% of the counts from within one effective radius) into 90 point sources, of which
Low-Mass X-Ray Binaries and Globular Clusters in Early-Type Galaxies
A high fraction of the low-mass X-ray binaries (LMXBs) in early-type galaxies are associated with globular clusters (GCs). Here we discuss the correlations between LMXBs and GCs in a sample of four
Resolving the Bondi Accretion Flow toward the Supermassive Black Hole of NGC 3115 with Chandra
Gas undergoing Bondi accretion onto a supermassive black hole (SMBH) becomes hotter toward smaller radii. We searched for this signature with a Chandra observation of the hot gas in NGC 3115, which
Flows of X-ray gas reveal the disruption of a star by a massive black hole
Flows of hot, ionized gas are detected in high-resolution X-ray spectra of a nearby tidal disruption event, ASASSN-14li in the galaxy PGC 043234, consistent with a rotating wind from the inner, super-Eddington region of a nascent accretion disk, or with a filament of disrupted stellar gas near to the apocentre of an elliptical orbit.
Resolving the Mystery of X-Ray Faint Elliptical Galaxies
Chandra observations of the X-ray-faint elliptical galaxy NGC 4697 resolve much of the X-ray emission (61% within one effective radius) into ~80 point sources, of which most are low-mass X-ray
The lack of very ultraluminous X-ray sources in early-type galaxies
We have searched for ultraluminous X-ray sources (ULXs) in a sample of 28 elliptical and S0 galaxies observed with Chandra. We find that the number of X-ray sources detected at a flux level that
O VI Observations of Galaxy Clusters: Evidence for Modest Cooling Flows
A prediction of the galaxy-cluster cooling flow model is that as gas cools from the ambient cluster temperature, emission lines are produced in gas at subsequently decreasing temperatures. Gas