TITLE: GCN CIRCULAR NUMBER: 10810 SUBJECT: GRB 100528A: SuperAGILE Localization of a Long GRB DATE: 10/05/28 08:23:17 GMT FROM: Marco Feroci at IASF/INAF E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, F. Lazzarotto, L. Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda (INAF/IASF Rome), G. Barbiellini, F. Longo, E. Moretti (INFN Trieste), A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli (INAF/IASF Bologna), A. Giuliani, A. Chen, S. Mereghetti, F. Perotti, P. Caraveo (INAF/IASF Milan), M. Tavani, G. Pucella, V. Vittorini, A. Argan, A. Trois, G. Piano, S. Sabatini (INAF/IASF Rome), A. Pellizzoni, M. Pilia (INAF/OA Cagliari), S. Vercellone, F. D'Ammando (INAF/IASF Palermo), P. W. Cattaneo, A. Rappoldi (INFN Pavia), P. Picozza, A. Morselli, E. Striani, (INFN Roma-2), M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), P. Giommi, C. Pittori, F. Lucarelli, P. Santolamazza, F. Verrecchia (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, report: "SuperAGILE detected a gamma ray burst on 28 May 2010, at 01:48:05 UT. The event had a duration of about 20 s in the 20-60 keV energy range, with a single peak structure. Due to the AGILE spinning operative mode, the measured duration may be a lower limit. The burst position was reconstructed as (RA, Dec) (311.119, 27.810) deg, which is: RA(J2000) = 20h 44m 28.52s Dec(J2000) = 27d 48' 35.80" with an uncertainty of 5' radius. The given uncertainty accounts for both the statistical and systematic errors. AGILE MCAL reports significant detection above 1.4 MeV. An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress." This message may be cited.