Búsqueda sistemática de GRBs Peculiares, tipo GRB200826A, en el Tercer Catálogo de Swift/BAT.

Abstract

The objective of this research is to search for peculiar gamma-ray bursts (GRBs), that is, short events (SGRBs) according to their duration, whose true nature could be associated with long events (LGRBs). As background we find the case of GRB~200826A that has a duration of approximately 1 second. After analyzing its spectral properties and properties of its host galaxy, GRB~200826A was found to be more consistent with LGRBs despite its short duration. To identify additional peculiar GRBs that do not follow the canonical temporal-spectral classification, we analyzed the third Swift/BAT Gamma-Ray Burst catalog. We consider parameters such as the emission time of 90% of the counts, the isotropic and peak energy (condensed in the Amati relation), and the spectral delay (obtained through the cross-correlation function) between different energy bands. By establishing the Amati relationship for the sample (with known redshifts), we find 8 GRBs that do not fall in the expected isotropic energy-peak energy plane according to the canonical classification. This group of GRBs represents a novel sample of events that do not follow the canonical classification and motivates to settle a new way to identify GRB’s progenitors.