Study of Faint Galaxies in the Field of GRB 021004

TL;DR

This study analyzes faint galaxies around GRB 021004 using multi-band observations, constructing galaxy counts, photometric redshifts, and examining large-scale structures in the field.

Contribution

It provides a detailed catalog of galaxies with photometric redshifts and investigates the large-scale structure around a gamma-ray burst field.

Findings

Galaxy counts up to magnitude limits in multiple bands.

Photometric redshifts for 183 galaxies.

Estimates of super-large-scale structure sizes.

Abstract

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.