GCN Circular 37572
Subject
EP240919a: INTEGRAL SPI-ACS confirmation of reported high-energy counterpart
Date
2024-09-20T13:35:34Z (3 months ago)
From
Aishwarya L Thakur at INAF-IAPS, Rome <aishth@outlook.com>
Via
Web form
James Rodi, Aishwarya Linesh Thakur, Luigi Piro, Lorenzo Natalucci and Giulia Gianfagna (INAF-IAPS) report:
Following the detection of the fast X-ray transient EP 240919a by the WXT (GCN 37561) and the associated gamma-ray counterpart (Fermi-GBM, GCN 37563), we searched for corresponding emission in the INTEGRAL SPI-ACS data. In a 1s binning light curve above 80 keV, we tentatively find an untriggered pulse temporally coincident with the WXT and GBM detections, with an approximate duration of 20 sec.
The approximate peak count rate is 33000 cts/s over a median background rate of 32600 cts/s.
This work is based on observations with INTEGRAL, an ESA project with instruments and a science data centre funded by ESA member states (especially the PI countries: Denmark, France, Germany, Italy, Switzerland, and Spain), and with the participation of Russia and the USA. The SPI-ACS detector system has been provided by MPE Garching/Germany.