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We present an analysis of BVRcIc observations of the field sized around 4 x 4 centered at the host galaxy of the gamma-ray burst GRB 021004 with the 6-m BTA telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We measured the magnitudes and constructed the color diagrams for 311 galaxies detected in the field (S/N > 3). The differential and integral counts of galaxies up to the limit, corresponding to 28.5 (B), 28.0 (V), 27.0 (Rc), 26.5 (Ic) were computed. We compiled the galaxy catalog, consisting of 183 objects, for which the photometric redshifts up to the limiting magnitudes 26.0 (B), 25.5 (V), 25.0 (Rc), 24.5 (Ic) were determined using the HyperZ code. We then examined the radial distribution of galaxies based on the z estimates. We have built the curves expected in the case of a uniform distribution of galaxies in space, and obtained the estimates for the size and contrast of the possible super-large-scale structures, which are accessible with the observations of this type.
We present polarimetric observations of the afterglow of gamma-ray burst (GRB) 021004, obtained with the Nordic Optical Telescope (NOT) and the Very Large Telescope (VLT) between 8 and 17 hours after the burst. Comparison among the observations shows
Reionizing the Universe with galaxies appears to require significant star formation in low-mass halos at early times, while local dwarf galaxy counts tell us that star formation has been minimal in small halos around us today. Using simple models and
We present U,B,V,R_C,and I_C photometry of the optical afterglow of the gamma-ray burst GRB 021004 taken at the Nordic Optical Telescope between approximately eight hours and 30 days after the burst. This data is combined with an analysis of the 87 k
The Milky Way ultra-faint dwarf galaxies (UFDs) contain some of the oldest, most metal-poor stars in the Universe. We present [Mg/Fe], [Si/Fe], [Ca/Fe], [Ti/Fe], and mean [alpha/Fe], abundance ratios for 61 individual red giant branch stars across 8
The CCD magnitudes in Johnson $B,V$ and Cousins $R$ and $I$ photometric passbands are determined for the bright long duration GRB 021004 afterglow from 2002 October 4 to 16 starting $sim$ 3 hours after the $gamma-$ray burst. Light curves of the after