{
  "circularId": 45919,
  "body": "S. Yatsuzuka (Ehime U.) H. Negoro, M. Nakajima, K. Saito, T. Yokoyama, M. Wada (Nihon U.),\nT. Mihara, A. Aoyama, M. Ota, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN),\nT. Sakamoto, M. Serino, S. Sugita, Y. Kawakubo, H. Hiramatsu, T. Kato, A. Yoshida (AGU),\nY. Tsuboi, Y. Ishihara, H. Ogaki (Chuo U.),\nM. Shidatsu, C. Kang, M. Uenishi, T. Usuki, H. Aoe (Ehime U.),\nI. Takahashi, Y. Yatsu (Science Tokyo),\nS. Nakahira, S. Ueno, H. Tomida, M. Kurihara (JAXA),\nY. Ueda, K. Fujiwara, S. Kobayashi (Kyoto U.),\nM. Yamauchi, M. Nishio, C. Hiraizumi (Miyazaki U.),\nK. Yamaoka (Nagoya U.),\nM. Sugizaki (Kanazawa U.),\nW. Iwakiri (Chiba U.),\nT. Kawamuro (Osaka U.),\nS. Yamada (Tohoku U),\nS. Ogawa (TUS)\n\nThe MAXI/GSC nova alert system triggered a bright uncatalogued \nX-ray transient source at 05:36:19 UT on 12 October 2026.\nAssuming that the source flux was constant over the transit,\nwe obtain the source position at\n(R.A., Dec) = (297.193 deg, -36.587 deg) = (19 48 46, -36 35 14) (J2000)\nwith a 90% C.L. statistical error of 0.32 deg and an additional \nsystematic uncertainty of 0.1 deg (90% containment radius).\nThe X-ray flux averaged over the scan was 245 +- 43 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) = (297.452, -37.121) deg = (19 49 48, -37 07 15) (J2000)\n(R.A., Dec) = (297.946, -36.618) deg = (19 51 47, -36 37 04) (J2000)\n(R.A., Dec) = (296.663, -35.796) deg = (19 46 39, -35 47 45) (J2000)\n(R.A., Dec) = (296.166, -36.294) deg = (19 44 39, -36 17 38) (J2000)\n\nThere was no significant excess flux in the previous transit at 04:03 UT\nand in the next transit at 07:09 UT with an upper limit of 20 mCrab for each.\n",
  "submittedHow": "web",
  "submitter": "Motoko Serino at Aoyama Gakuin U. <serino@phys.aoyama.ac.jp>",
  "createdOn": 1791790286062,
  "eventType": [
    "GRB"
  ],
  "subject": "GRB 261012A: MAXI GSC detection",
  "eventId": "GRB 261012A",
  "format": "text/plain"
}