{
  "bibcode": "1998GCN...153....1F",
  "body": "SGR 1900+14\n        M. Feroci, P. Soffitta, E. Costa, Istituto di Astrofisica\nSpaziale, CNR, Rome, and F. Frontera, Istituto Tecnologie e Studio\nRadiazioni Extraterrestri, CNR, Bologna, on behalf of the\nBeppoSAX/GRBM team, and M. Tavani, Istituto di Fisica\nCosmica, CNR, Milano, and Columbia Astrophysics Laboratory, New York,\nreport:\n\n\"The Gamma-Ray Burst Monitor (GRBM) onboard BeppoSAX was triggered by\nthe event reported by Cline et al. (IAUC 7002) on Aug. 27.4321259.\nThe event showed a fast rise (<1s) and an exponential-like decay,\nlasting more than 300s. The event was observed at an off-set angle of\nabout 56 degrees from the axis of GRBM unit 1, and showed a peak intensity\nin (40-700 keV) of about 64000 c/s.  The event was clearly detected\nabove 100 keV.  A preliminary analysis shows that the spectrum is\nhard during the initial 1s, followed by a sudden softening.  Subsequent\nspectral evolution shows a progressive hardening.\nThe near-5s periodicity reported by Cline et al. (IAUC 7002) is evident\nin the GRBM data for the entire duration of the event.\nIn addition, starting from about 35s after the event onset, the GRBM\nclearly detected a periodic pattern of subpulses for each near-5s\noscillation.  The repetitive pattern is made of four subpulses of period\nnear-1s.\nMore detailed temporal and spectral analyses are in progress.\"",
  "circularId": 153,
  "createdOn": 904664979000,
  "email": "feroci@ias.rm.cnr.it",
  "subject": "SGR1900+14, BeppoSAX-GRBM observations",
  "submitter": "Marco Feroci at IAS/CNR Frascati  <feroci@ias.rm.cnr.it>"
}