TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3472 SUBJECT: INTEGRAL detection of GRB 050525 DATE: 05/05/25 09:16:08 GMT FROM: Sandro Mereghetti at IASF/CNR D. Gotz, S. Mereghetti (IASF, Milano), N. Mowlavi, S. Shaw, M. Beck (ISDC, Versoix), J. Borkowski (CAMK, Torun) on behalf of the IBAS Localization Team and N. Lund (DSRI, Copenhagen) on behalf of the ISWT report: Offline analysis of the IBAS data showed that GRB 050525 discovered by Swift (Band et al. GCN 3466, Markwardt et al. GCN 3467), has been detected also by the IBIS/ISGRI instrument on board INTEGRAL. The burst occurred at an off-axis angle of 14.7 degrees, very close to the edge of the IBIS/ISGRI field of view, and illuminated through the coded mask only 6% of the detector surface. The preliminary value of the peak flux is 33 photons (3.2E-6 ergs)/cmsq/s (1 sec integration time, 20-200 keV). Owing to a small gap caused by telemetry saturation, we can only derive a lower limit on the fluence of 144 photons (1.2E-5 ergs)/cmsq (12 s integration time, 20-200 keV). A plot of the multi peaed light curve is posted at: http://ibas.mi.iasf.cnr.it/IBAS_Results.html This message can be cited.