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Study of Faint Galaxies in the Field of GRB 021004

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 نشر من قبل Timur Fatkhullin
 تاريخ النشر 2010
  مجال البحث فيزياء
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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.



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