We report on a search for gravitational waves from binary black hole inspirals in the data from the second science run of the LIGO interferometers. The search focused on binary systems with component masses between 3 and 20M&sun;. Optimally oriented binaries with distances up to 1 Mpc could be detected with efficiency of at least 90%. We found no

We describe improved modelling of the emission by dust in a toroidal-like structure heated by a central illuminating source within active galactic nuclei (AGNs). We have chosen a simple but realistic torus geometry, a flared disc, and a dust grain distribution function including a full range of grain sizes. The optical depth within the torus is

The paradox of apparent optical associations of galaxies with very different redshifts, the so-called anomalous redshift problem, is around 35 years old, but is still without a clear solution and is surprisingly ignored by most of the astronomical community. Statistical correlations among the positions of these galaxies have been pointed out by

In response to the detection of the X-ray source Swift J0732.5-1331 (ATEL #697, #735, #757, #760), we observed its optical counterpart with the Mt. Hopkins 1.5m telescope equipped with the FAST spectrograph. A total of 22 spectra covering 3480-7410 A were acquired between Jan 22 and Mar 1. A 3" slit provided 6 A FWHM resolution. In addition, on

We present the optical identification and characterization of counterparts of four objects previously cataloged as ultraluminous X-ray (ULX) sources. The objects were selected from the E. Colbert & A. Ptak catalog. The optical counterparts are identified as pointlike objects with magnitudes in the range of ~17-19. The optical spectra of three of

We report optical and near-infrared (NIR) observations of the field containing the neutron star X-ray transient XTE J1739-285 (IAUC #7300, ATel #622). The recently reported Chandra localization (ATel #777) provides a significant improvement over the Swift XRT position reported in ATel #602, facilitating the identification of potential counterparts