{
  "bibcode": "2012GCN.13282....1S",
  "body": "N. Serita, H. Negoro, M. Nakajima, M. Asada, H. Sakakibara (Nihon U.), \nM. Serino, T. Mihara, M. Sugizaki, T. Yamamoto, M. Matsuoka (RIKEN), \nS. Nakahira, S. Ueno, H. Tomida, M. Ishikawa (JAXA),\nN. Kawai, M. Morii, R. Usui, K. Ishikawa (Tokyo Tech),\nA. Yoshida (AGU),\nH. Tsunemi, M. Kimura (Osaka U.), \nY. Ueda, K. Hiroi, M. Shidatsu, R. Sato (Kyoto U.),\nY. Tsuboi, M. Higa (Chuo U.)\nM. Yamauchi, Y. Nishimura, T. Hanayama, K. Yoshidome (Miyazaki U.), \nK. Yamaoka (Waseda U.)\nreport on behalf of the MAXI team:\n\nDuring a scan transit centered at UT 2012-05-10T08:47:44,\nMAXI/GSC detected a short X-ray transient lasting about 27 seconds \nwithin the 42 seconds triangular transit response of MAXI/GSC.\nJudging from its hardness ratio, \nthis transient is probably a gamma-ray burst.\n\nAssuming that the source flux was constant over the transit, \nwe obtain the source position at\n\n(R.A., Dec) = (+44.285 deg, +72.850deg) = ( 02 57 08.60, +72 51 00.8 )(J2000)\n\nwhich has a statistical uncertainty of 10 arcmin at the 90% confidence limit \nand an additional systematic uncertainty of 6 arcmin (90% containment radius).\nDue to a short burst duration, the uncertainty for the scan direction is possibly larger than this estimation.\nWithout assuming a constant flux of the source,\na rectangular sky region of 90% confidence\nis 0.4 degrees by 1.4 degrees with the following corners:\n\n(R.A., Dec) = (+41.76 deg, +72.60 deg) = (02 47  2, +72 36 12)(J2000)\n(R.A., Dec) = (+41.77 deg, +73.02 deg) = (02 47  4, +73 01 20)(J2000)\n(R.A., Dec) = (+46.50 deg, +72.97 deg) = (03 06  0, +72 58  4)(J2000)\n(R.A., Dec) = (+46.40 deg, +72.55 deg) = (03 05 36, +72 32 59)(J2000).\n\nThe preliminary flux estimate (4-10 keV) of the source was 330+-40 mCrab.\n\nThere was no significant detection at the transit location in the\nprevious and the following orbits (92 min before and after the detection) \nwith an upper limit of 20 mCrab.\n\nFollow-up observations are encouraged.",
  "circularId": 13282,
  "createdOn": 1336657536000,
  "email": "motoko@crab.riken.jp",
  "subject": "GRB 120510A: MAXI/GSC detection of a burst",
  "submitter": "Motoko Suzuki at RIKEN  <motoko@crab.riken.jp>",
  "eventId": "GRB 120510A"
}