\ photons\cdot cm^{-2}\cdot s^{-1}\cdot}$ keV), when the greater part of [$\gamma$]{}–ray burst energy was released at the annihilation emission frequency during a time of $\approx 0.1$ s (Atteia et al., 1987; Vrba et al., 1995). It could be expected that a supposed compact object, which was connected with this [$\gamma$]{}–ray burst, is one of such nearest objects, that has probably undergone a kind of explosion on its surface. In next Sections, with the use of the above mentioned, by the example of GRB790613 event it will be shown how an observational problem of search for such “cold” compact objects can be stated under the conditions, when we have to conduct optical search for weak sources by studying very big areas in the sky.

Observations
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The observational data were obtained with the CCD camera of $580\times
520$ pixels placed at the prime focus of the 6 m telescope of SAO RAS. The CCD chip has rectangular pixels of $24\times18\  \mu$m, resulting in an image scale of $0\farcs205\times 0\farcs154$ per pixel. We obtained the data with Cousins [*BVR*]{} filters. Normal program exposures were 600 s, 500 s or 400 s for the [*BVR*]{} filters. Longer exposures are not reasonable because of 