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arXiv · 2401.08946

A blind search for intraday gamma-ray transients with Fermi-LAT: Detections of GRB and solar emissions

D. A. Prokhorov·A. Moraghan
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Abstract

We present a search for intraday transient gamma-ray signals using 15.4 years of the Fermi Large Area Telescope data. The search is based on a recently developed variable-size sliding-time-window (VSSTW) analysis and aimed at studying variable gamma-ray emission from gamma-ray bursts and the Sun. We refined the algorithm for searches for transient sources in order to solve the search problem within a reasonable amount of CPU time. These refinements allowed us to increase the number of gamma-ray bursts, solar flares, and quiescent solar events detected with the VSSTW technique by several times compared to the previous VSSTW search. The current search revealed a new gamma-ray signal recorded with Fermi-LAT on 2018 January 12. This signal is probably from a GRB and deserves an exploration of the existing archival multi-wavelength observations in order to identify it in an unambiguous way. We also report a gamma-ray signal from the solar flare on 2023 December 31 that occurred during the 25th solar cycle.

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D. A. Prokhorov, A. Moraghan. 2024-01-17. A blind search for intraday gamma-ray transients with Fermi-LAT: Detections of GRB and solar emissions. https://doi.org/10.1051/0004-6361%2F202449251

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