Pipeline for Optical Transients Search and Identification

Search, classification and followed study of optical counterparts of cosmic gamma-ray burst (GRB) and gravitational wave events is a difficult research problem in the modern multi-messenger astronomy. Initial localization of events is provided by space gamma and x-ray observatories (gamma-ray burst) or by ground-based laser interferometers LIGO/Virgo/KAGRA (LVC) (gravitational wave events). Typical localization area is about of several hundreds of square degrees what is the cause of poor accuracy of the used detectors, especially for the detectors of gravitational waves. Temporarily, the one of the most interesting multi-messenger events is GW 170817 – binary neutron star merger with the total mass of ∼2.74M⊙ has been firstly discovered in gravitational waves and later observed in gamma-rays (as GRB 170817) and in optical light (as kilonova AT 2017gfo). AT 2017gfo is still the only one discovered kilonova, associated with a binary neutron star merger. It should be noted that the search of the AT 2017gfo was difficult due to the fact that astronomers had to observe the sky area of about 28 square degrees and identify the transient among the ~ 105 optical sources down to about 21-st apparent magnitude. The amount of generated data in such surveys is large, so the data processing with the pipeline becomes relevant. In this diploma, the software pipeline for automatic search and identification of optical transients in the real-time mode is developed; the results of applying the current implementation of the pipeline units is discussed as applied to processing observations of the cosmic gamma-ray burst GRB 200829A. Chapters 2 and 4 will be published on proceedings of XXIII DAMDID Conference (October 2021), “Pankov et al. Pipeline for detection of transient objects in optical surveys 2021” (paper in preparation).