TITLE: GCN CIRCULAR NUMBER: 7866 SUBJECT: GRB 080607: AGILE-MCAL observation of the prompt emission DATE: 08/06/09 15:44:57 GMT FROM: Marco Feroci at IASF/INAF M. Marisaldi, F. Fuschino, M. Galli, C. Labanti, A. Bulgarelli, F. Gianotti, M. Trifoglio, G. Di Cocco (INAF/IASF Bologna), E. Costa, E. Del Monte, I. Donnarumma, Y. Evangelista, M. Feroci, I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda, P. Soffitta (INAF/IASF Roma), F. Fornari, A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni, F. Perotti, M. Fiorini, P. Caraveo (INAF/IASF Milano), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, F. Longo, E. Vallazza (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2), M. Prest (Universita` dell'Insubria), P. Lipari, D. Zanello (INFN Roma-1), and P. Giommi, C. Pittori, (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team, report: "The Swift localized GRB 080607 (Mangano et al., GCN 7847; Stamatikos et al., GCN 7852) triggered the Mini-Calorimeter (MCAL) instrument onboard the AGILE satellite at 06:07:23 UT (=T0). The MCAL instrument covers the energy range 350 keV - 10 MeV, without imaging capabilities. Using the preliminary in-flight calibration and assuming a Crab-like spectrum, we can estimate the fluence in the 350-700 keV energy band to be (23 +/- 7) photons/cm2 corresponding to (1.8 +/- 0.5)x10^-5 erg/cm2, in the time interval T0-T0+14 s. The 1-s peak flux measured at T0+5.1 s is (4.2 +/- 1.2) photons/cm2/s in the same energy band. The GRB was detected also in the 1.4-2.8 MeV energy band with a 10 sigma significance in the 256-ms time window. We note that the quoted fluence is in agreement within errors with that obtained using the Konus-Wind spectrum reported in Golenetskii et al., GCN 7862. Assuming the spectral model reported in GCN 7862, an agreement in flux within 10% for the energy band 350-700 keV is obtained. The Swift localization is at about 113 degrees off-axis with respect to the AGILE pointing, so well out of the field of view of the AGILE Gamma-Ray Imaging Detector (GRID), sensitive in the 50 MeV - 50 GeV energy range. Analysis of the GRID count rate does not show any detection. This GRB triggered also SuperAGILE and was detected at about 17 sigma significance level in the 18-60 keV band, although it was well outside the field of view, and was detected through the collimator shielding." This message may be cited.