{
"subject": "INTEGRAL observation of S190408an",
"bibcode": "2019GCN.24066....1S",
"createdOn": 1554757489000,
"circularId": 24066,
"submitter": "Volodymyr Savchenko at ISDC,U of Geneve ",
"email": "savchenk@in2p3.fr",
"body": "Volodymyr Savchenko, Carlo Ferrigno�� (ISDC/UniGE, Switzerland)\nJames Rodi,�� (IAPS-Roma, Italy)\nSandro Mereghetti (INAF IASF-Milano, Italy)\n\non behalf of the INTEGRAL multi-messenger collaboration:\nhttps://www.astro.unige.ch/cdci/integral-multimessenger-collaboration\n\n\nUsing INTEGRAL we have performed a search for a prompt gamma-ray\ncounterpart of S190408an.\n\nAt the time of the event (2019-04-08 18:18:02.29 UTC, hereafter T0),\nINTEGRAL was operating in nominal mode. The peak of the event\nlocalization probability was at an angle of 115 deg with respect to\nthe spacecraft pointing axis. This orientation implies strongly\nsuppressed response of IBIS, strongly suppressed response of\nIBIS/Veto, and somewhat suppressed response of SPI-ACS.\n\nThe background within +/-300 seconds around the event was very stable.\nWe do not detect any significant counterparts and estimate a 3-sigma\nupper limit on the 75-2000 keV fluence of 2.5e-07 erg/cm^2 for a burst\nlasting less than 1 s with a characteristic short GRB spectrum (an\nexponentially cut off power law with alpha=-0.5 and Ep=600 keV)\noccurring at any time in the interval within 300 s around T0.\n\nFor a typical long GRB spectrum (Band function with alpha=-1,\nbeta=-2.5, and Ep=300 keV), the derived peak flux upper limit is\n~2.1e-07 (8.1e-08) erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV\nenergy range."
}