Black hole candidates (BHCs) are increasingly found as luminous hard x-ray sources, with spectra exending up to 100-200 keV, which undergo transient outbursts and appear as "X-ray novae" for durations of typically 10-100 days. The BATSE detectors on CGRO constitute a powerful all-sky monitor and have detected the brightest of these, with peak

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We present two geometrical methods to analyse the cosmic microwave background data along a strip in the sky. These methods are motivated by the fact that the temperature fluctuation field, on large angular scales, is not ergodic on the cosmic photosphere. This property is examined in the context of different experimental configurations. The methods

The results of a UBVR photometric study in the field of the open cluster IC 1311 are presented. A comparison with previously published results on NGC 7044, based on measurements secured during the same observing run, leads to a self-consistent constraints to the parameters of the cluster. The location of selected samples of giant and unevolved

An international collaboration of fourty scientists have been involved in multifrequency observations of the blazar OJ 287, as well as of a few other complementary objects, taken both photometrically and spectroscopically. We present the optical light curve of OJ 287 obtained between the fall of 1993 through the present. Over 1200 photometric

We present a study of high-velocity gas in the direction of 13 halo sub-dwarfs located at absolute value of z approximately equals 0.5-2 kpc and of 8 early-type stars in the Galactic disk at d approximately equals 1-4 kpc. For each line of sight of our sample we collected Ca II and Na I absorption spectra with the 2.5-m Isaac Newton Telescope at La