Vv. Sokolov et al., THE SEARCH AND INVESTIGATION OF FAINT BLUE STAR-LIKE OBJECTS IN THE SMALL GRB ERROR BOXES, Astrophysics and space science, 231(1-2), 1995, pp. 343-346
A central part of the GRB 790613 field is investigated, which contains
about 1/3 of the area of 99% confidence of the GRB localization. Up t
o V approximate to 25 no blue optical counterparts were found. This ca
n be interpreted as the absence in the field of single compact objects
of the neutron star type as a possible potential source of gamma-burs
t, up to a distance of approximate to 30 pc.