TITLE: GCN CIRCULAR NUMBER: 23560 SUBJECT: GRB 181225A: AGILE/MCAL detection of a burst DATE: 18/12/25 16:22:35 GMT FROM: Alessandro Ursi at INAF/IAPS A. Ursi (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C. Casentini, Y. Evangelista, G. Piano (INAF/IAPS), F. Lucarelli, C. Pittori, F. Verrecchia (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, F. Fuschino, N. Parmiggiani (INAF/OAS-Bologna), M. Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois (INAF/OA-Cagliari), I. Donnarumma (ASI), F. Longo (Univ. Trieste and INFN Trieste), A. Giuliani (INAF/IASF-Mi), report on behalf of the AGILE Team: The AGILE Mini-CALorimeter (MCAL) detected a short burst at T0 = 2018-12-25 11:44:11.76 +/- 0.01 s (UTC). The event lasted about 1.2 s and released a total number of ~1580 counts in the detector (in the 0.4-100 MeV energy range), above an average background rate of 750 counts / s. Further analysis is still in progress. The AGILE-MCAL detector has a full solid angle acceptance, and is operational in the range 0.4 - 100 MeV.