{
  "bibcode": "2018GCN.23103....1Y",
  "body": "F. Yatabe, S. Nakahira, T. Mihara, Y. Takao, M. Matsuoka (RIKEN),\nM. Serino, T. Sakamoto,  S. Sugita, Y. Kawakubo, T. Hashimoto, A. Yoshida (AGU),\nH. Negoro, M. Nakajima, A. Sakamaki, W. Maruyama (Nihon U.),\nN. Kawai, M. Sugizaki, Y. Tachibana, K. Morita (Tokyo Tech),\nS. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai (JAXA),\nY. Ueda, A. Tanimoto, T. Morita, S. Yamada (Kyoto U.),\nY. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.),\nH. Tsunemi, T. Yoneyama (Osaka U.),\nM. Yamauchi, K. Hidaka, S. Iwahori (Miyazaki U.),\nT. Kawamuro (NAOJ),\nK. Yamaoka (Nagoya U.),\nM. Shidatsu (Ehime U.)\nreport on behalf of the MAXI team:\nThe MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient\nsource at  11:38:25 UT on 9 August 2018.\nAssuming that the source flux was constant over the transit,\nwe obtain the source position at\n(R.A., Dec) = (297.793 deg, -34.663 deg) = (19 51 10, -34 39 46) (J2000)\nwith a 90% C.L. statistical error of 0.09 deg and an additional systematic\nuncertainty of 0.1 deg (90% containment radius).\nThe X-ray flux averaged over the scan was 890 +- 57 mCrab\n(4.0-10.0keV, 1 sigma error).\nWithout assumptions on the source constancy,we obtain a rectangular error\nbox for the transient source with the following corners:\n(R.A., Dec) = (297.202, -33.964) deg = (19 48 48, -33 57 49) (J2000)\n(R.A., Dec) = (297.086, -34.046) deg = (19 48 20, -34 02 46) (J2000)\n(R.A., Dec) = (298.358, -35.535) deg = (19 53 25, -35 32 04) (J2000)\n(R.A., Dec) = (298.475, -35.451) deg = (19 53 54, -35 27 03) (J2000)\nThere was no significant excess flux in the previous transit at UT 10:05\nwith an upper limit of 20 mCrab.",
  "circularId": 23103,
  "createdOn": 1533817921000,
  "email": "nakahira@crab.riken.jp",
  "subject": "GRB 180809A: MAXI/GSC detection",
  "submitter": "Satoshi Nakahira at RIKEN  <nakahira@crab.riken.jp>",
  "eventId": "GRB 180809A"
}