AGILE detection of enhanced gamma-ray activity from the blazar BL Lac
ATel #14839; G. Piano (INAF/IAPS), C. Pittori (SSDC and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), S. Vercellone (INAF/OA-Brera), I. Donnarumma (ASI), A. Bulgarelli, V. Fioretti, N. Parmiggiani, A. Addis, L. Baroncelli, A. Di Piano (INAF/OAS-Bo), F. Verrecchia, F. Lucarelli (SSDC and INAF/OAR), M. Cardillo, A. Ursi, C. Casentini (INAF/IAPS), F. Gianotti, M. Trifoglio (INAF/OAS-Bo), A. Giuliani, S. Mereghetti, P. Caraveo, F. Perotti (INAF/IASF-Mi), A. Chen (Wits University), A. Argan, E. Costa, E. Del Monte, Y. Evangelista, M. Feroci, L. Foffano, I. Lapshov, E. Menegoni, L. Pacciani, P. Soffitta, V. Vittorini (INAF/IAPS), F. Lazzarotto (INAF/OAPD), G. Di Cocco, F. Fuschino, M. Galli, C. Labanti (INAF/OAS-Bo), M. Marisaldi (University of Bergen), A. Pellizzoni, M. Pilia, A. Trois (INAF/OA-Cagliari), G. Barbiellini (INFN Trieste), F. Longo (Univ. Trieste and INFN Trieste), E. Vallazza (INFN Milano Bicocca), A. Morselli, P. Picozza (INFN and Univ. Roma Tor Vergata), M. Prest (Univ. dell'Insubria), P. Lipari, D. Zanello (INFN and Univ. Roma Sapienza), P. W. Cattaneo, A. Rappoldi (INFN Pavia), A. Ferrari (Univ. Torino and CIFS), F. Paoletti (East Windsor RSD Hightstown and INAF/IAPS), L. A. Antonelli (INAF/OAR), P. Giommi, L. Salotti, G. Valentini, and F. D'Amico (ASI)
on 9 Aug 2021; 15:27 UT
Credential Certification: Giovanni Piano (giovanni.piano@inaf.it)
Subjects: Gamma Ray, >GeV, AGN, Black Hole, Blazar, Quasar
AGILE is detecting enhanced gamma-ray activity above 100 MeV from the blazar BL Lacertae. Integrating from 2021-08-06 UT 18:00:00 to 2021-08-08 UT 18:00:00 (MJD: 59432.75 - 59434.75), a preliminary multi-source maximum likelihood analysis yields a detection significance greater than 7 sigma and a flux F(>100 MeV) = (6 +/- 1) x 10^-6 photons/cm^2/s.
BL Lac entered in a multiwavelength outburst at the beginning of July 2021 (ATel #14751, ATel #14773, ATel #14774, ATel #14777, ATel #14782, ATel #14783, ATel #14820, ATel #14826). This detection represents the peak gamma-ray emission of the current outburst, as detected by AGILE so far.
The AGILE-GRID detection was obtained while AGILE is observing in spinning mode, surveying a large fraction of the sky each day. The source can be monitored with the public mobile application "AGILEScience" developed by the AGILE Team, available for both Android and iOS devices.
Multifrequency observations of BL Lac are strongly encouraged.
