TITLE: GCN CIRCULAR NUMBER: 15882 SUBJECT: GRB 140219A: MAXI/GSC detection DATE: 14/02/26 03:08:11 GMT FROM: Motoko Suzuki at RIKEN M. Serino (RIKEN), S. Ueno, H. Tomida, S. Nakahira, M. Kimura, M. Ishikawa, Y. E. Nakagawa (JAXA), T. Mihara, M. Sugizaki, M. Morii, J. Sugimoto, T. Takagi, A. Yoshikawa, M. Matsuoka (RIKEN), N. Kawai, R. Usui, T. Yoshii, Y. Tachibana (Tokyo Tech), A. Yoshida, T. Sakamoto, Y. Nakano, Y. Kawakubo, H. Ohtsuki (AGU), H. Tsunemi, M. Sasaki (Osaka U.), H. Negoro, M. Nakajima, K. Fukushima, T. Onodera, K. Suzuki (Nihon U.), Y. Ueda, M. Shidatsu, T. Kawamuro, T. Hori (Kyoto U.), Y. Tsuboi, M. Higa (Chuo U.), M. Yamauchi, K. Yoshidome, Y. Ogawa, H. Yamada (Miyazaki U.), K. Yamaoka (Nagoya U.) report on behalf of the MAXI team: The MAXI/GSC detected a rapid increase of the count rate in all six working counters at 2014-02-19T19:45:58.15 UT. The time is consistent with GRB 140219A (Hurley et al., GCN 15864; Zhang, GCN 15866; Guiriec et al., GCN 15867; Golenetskii et al., GCN 15870). The IPN postion of GRB 140219A was not in the field of view of any of the MAXI Gas Slit Cameras, implying that the detected counts are produced by the hard X-rays that penetrated the Ti counter walls with Pb shiled, or the phosphor bronze collimator with Al housing of GSC, or by the Compton-scattered electrons induced by the gamma-rays. It suggests that this GRB was exceptionally bright and hard. The light curve shows an intense spike with a duration of ~0.2 s followed by a bright emission until T0+~2.5 s. A weak emission lasts until T0+~20 s. The peak count rate is ~2000 c/s per counter (GSC_3). The MAXI/GSC light curve of this GRB is available at http://maxi.riken.jp/news/en/?p=1101 . There was no significant excess flux in the transits before and after the GRB at UT 19:40 and 21:13 with an upper limit of 20 mCrab (4-10 keV, 1 sigma) for each. -- Motoko SERINO