We present a deep, wide-field optical survey of the young stellar cluster Alpha Per, in which we have discovered a large population of candidate brown dwarfs. Subsequent infrared photometric follow-up shows that the majority of them are probable or possible members of the cluster, reaching to a minimum mass of 0.035 Msun. We have used this list of

A good example of finding a signal buried in noise, a common problem in Astrophysics, is the search for stellar oscillations in the acoustic power spectrum of solar-like stars. In this work it is shown that it is possible to find this type of signal in the power spectrum of stellar oscillations if the peaks are ``almost'' equally spaced in

The varying global distribution of stars, or specifically, their concentration Cr_e, within elliptical galaxies and spiral galaxy bulges is intimately related to the mass of their central supermassive black holes (Mbh), such that log (Mbh/Msun) = 6.81(±0.95)Cr_e + 5.03±0.41. This correlation has a Spearman correlation coefficient rs=0.91, and a

We present results from a Chandra survey of 11 nearby, face-on spiral galaxies. 24 observations totaling 900 ks of new and archival Chandra data reveal more than 1000 X-ray point sources associated with the galaxies, diffuse emission, and hundreds of serendipitous sources. We discuss source populations and luminosity functions and show that the

We have compiled a database of Chandra-HRC snapshot images covering most of the M31 disk. The database consists of 5 HRC fields. All fields were observed at 16 different epochs covering a baseline of nearly 2 years. The merged image has a mean total exposure time of 17 ks. These data were analyzed to measure the mean fluxes of ~130 sources, most of

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