{
  "bibcode": "2002GCN..1703....1R",
  "body": "A. Rau, V. Schoenfelder, A.v. Kienlin, G. Lichti G., N. Arend,\non behalf of the MPE INTEGRAL SPI-team;\n\nJ.-P. Roques on behalf of the Toulouse INTEGRAL\nSPI-team;\n\nJ. Borkowski, R. Walter, N. Produit on behalf of the INTEGRAL Science Data\nCenter (ISDC) Geneve;\n\nK. Hurley on behalf of the IPN team\n\nreport:\n\nThe Anticoincidence Shield (ACS) of the Spectrometer onboard the\nINTEGRAL satellite (SPI) was switched on on the 26th of October 2002.\nSince then, besides the major calibration and verification activities,\nthe ACS rates have already been monitored for GRBs. The ACS has\nregistered approximately 1 GRB per day, among them also the following\nIPN-localized GRBs 021027 (GCN#1658), 021102 (GCN#1667) and 021108\n(GCN#1679).\n\nThe first HETE-localized GRB detected by SPI ACS was GRB 021113\n(=H2449; GCN #1686).  The ACS lower energy threshold during this burst was\nset to ~100 keV, but this threshold is broad; there exists no high-energy\nthreshold. GRB 021113 was seen in the total ACS rate (all 91 BGO crystals)\nwith 4 sigma on a 1s time scale.\n\nThe ACS lightcurve of GRB 021113\n(http://www.mpe.mpg.de/gamma/instruments/integral/spi/acs/grb/021113_acs.html)\nshows a single, smooth peak (similar to the HETE light curve), with a\nmaximum occuring at 6:38:58 UT. The absolute timing of the ACS is known\nint the moment with an accuracy of ~100ms.\n\nContinued \"tuning\" of the energy threshold and burst verification\nalgorithm is anticipated over the coming weeks, before the ACS will be\nfully implemented into the INTEGRAL Burst Alert System (IBAS).\n\nAcknowledgement is given to INTEGRAL Science Working Team for making these\nburst data public.\n\nThis message is citable.",
  "circularId": 1703,
  "createdOn": 1037868758000,
  "email": "arau@xray.mpe.mpg.de",
  "subject": "GRB021113, SPI ACS observation",
  "submitter": "Arne Rau at MPI  <arau@xray.mpe.mpg.de>",
  "eventId": "GRB 021113"
}