Search for Very Short Bursts with the AGILE Mini-Calorimeter
Marisaldi, M. ; Labanti, C. ; Fuschino, F. ; Giommi, P. ; Salotti, L. ; et al.
May - 2009
DOI: 10.1063/1.3155937

Event Title : GAMMA‐RAY BURST: Sixth Huntsville Symposium
Published in: AIP Conference Proceedings. 1133, 415 (2009)
Publisher: AIP
type: Conference Proceedings

In this paper the results of the first months of burst search on very short time scales with the Mini‐Calorimeter (MCAL) on‐board the AGILE mission are presented. MCAL is equipped with a flexible on‐board trigger logic for autonomous GRB detection. In addition to standard trigger time windows, MCAL has been equipped with trigger capabilities on 16 ms, 1 ms and sub‐millisecond time windows. Since June 2008 burst search on these short time scales has been enabled, resulting in an average rate of 4 triggers/orbit, compliant with telemetry budget. An on‐ground rejection strategy is applied, allowing more sophisticated selection criteria than those allowed by the on‐board trigger logic. Triggers due to instrumental effects or geophysical phenomena can be spotted due to their photon‐by‐photon pattern; what remains after this cleaning is an almost unexplored territory and could shed light on the origin of very short bursts. The trigger criteria, as well as the on‐ground rejection strategy and the properties of the selected events will be described and discussed.

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