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We have studied the X-ray point source population of Centaurus A (NGC 5128) using data from four archival CHANDRA observations. We detected 272 point-like X-ray sources within a radius of 10 arcmin from the centre. Approximately half of these are CXB sources, with the remaining half being LMXBs. The spatial distribution of the LMXBs, both azimuthally averaged and 2-D, is consistent with the distribution of the K-band light observed in the 2MASS survey. After correction for the incompleteness effect we constrain the LMXB luminosity function down to 2 times 10^{36} erg/s, much lower than previous studies of LMXBs in elliptical galaxies. The obtained XLF flattens significantly below L_X = 5 times 10^{37} erg/s and follows the dN/dL proportional to 1/L law in agreement with the behaviour found earlier for LMXBs in the Milky Way and in the bulge of M31.
We detect 353 X-ray point sources, mostly low-mass X-ray binaries (LMXBs), in four Chandra observations of Centaurus A (NGC 5128), the nearest giant early-type galaxy, and correlate this point source population with the largest available ensemble of
The Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) is constructing a wide-field map of the resolved stellar populations in the extended halos of these two nearby, prominent galaxies. We present new Magellan/Megacam imaging of a $sim3$ de
We report measurements of the cluster X-ray luminosity function out to z=0.8 based on the final sample of 201 galaxy systems from the 160 Square Degree ROSAT Cluster Survey. There is little evidence for any measurable change in cluster abundance out
The XMM-Newton survey of the Coma cluster of galaxies covers an area of 1.86 square degrees with a mosaic of 16 pointings and has a total useful integration time of 400 ksec. Detected X-ray sources with extent less than 10 were correlated with catalo
The Advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO) has detected direct signals of gravitational waves (GWs) from GW150914. The event was a merger of binary black holes whose masses are $36^{+5}_{-4}M_{odot}$ and $29^{+4}_{-4}M_{