SHOT NOISE IN GAMMA-RAY BURSTS

We report on the analysis of the temporal behavior of five gamma-ray bursts, selected from the longest and the most intense ones in Mazets's catalog, recorded by the KONUS experiment onboard the Soviet probes Venera 11 and Venera 12. The aim of this research was to improve our understanding of nonperiodic features, such as red noise, already observed in gamma-ray bursts, but never analyzed in detail. The presence of a particular kind of non-Poissonian noise in the photon emission of gamma-ray bursts can add more insight into the unknown mechanisms at the origin of these phenomena. We report evidence in all of the five selected events for the presence of red noise, which can be interpreted in terms of a shot noise process with characteristic shot times in the range 0.4-2 s. These results are in agreement with those we obtained analyzing the data referring to the same events, recorded by other experiments on board spacecraft in the interplanetary network.