{
  "bibcode": "2021GCN.29350....1X",
  "body": "S. L. Xiong, F. J. Lu, S. N. Zhang, Y. Huang, Y. P. Chen,\nS. Xiao, C. Cai, X. Y. Zhao, B. X. Zhang,\nZ. H. An, C. Chen, G. Chen, W. Chen, M. Gao, K. Gong, D. Y. Guo,\nJ. J. He, B. Li, C. Li, C. Y. Li, J. H. Li, Q. X. Li,\nX. B. Li, X. Q. Li, Y. G. Li, X. H. Liang, J. Y. Liao, J. C. Liu,\nX. J. Liu, Y. Q. Liu, Q. Luo, X. Ma, G. Ou, W. X. Peng, R. Qiao,\nD. L. Shi, J. Y. Shi, L. M. Song, X. Y. Song, G. X. Sun, X. L. Sun,\nY. L. Tuo, C. W. Wang, J. Z. Wang, P. Wang, X. Y. Wen, Y. B. Xu,\nY. P. Xu, W. C. Xue, S. Yang, M. Yao, Q. B. Yi, C. Y. Zhang,\nD. L. Zhang, Fan Zhang, Fei Zhang, H. M. Zhang, K. Zhang, P. Zhang,\nY. Q. Zhang, Z. Zhang, S. Y. Zhao, Y. Zhao, C. Zheng,\nS. J. Zheng, X. Zhou (IHEP),\nreport on behalf of GECAM team:\n\nDuring the commissioning phase, GECAM-B was triggered in-flight by\na long burst at 2021-01-24T11:50:03.600 UTC (denoted as T0).\nIts alert data was promptly downlinked to the ground through the\nshort message service of BeiDou Navigation Satellite System (BDS).\nThe time latency of the first BeiDou message relative to the trigger time\nis about 1 minute.\n\nAccording to the BDS alert data, this burst mainly consists of\na single pulse with a duration of about 60 s.\nThe spectrum is very soft with not much emission above about 30 keV.\nAn automatic on-ground localization was calculated using the light curves\nand spectrum. Although the in-flight calibration of energy response and\nlocalization has not been finalized yet, GECAM-B localized this burst to\nthe following position (J2000):\n\nRa: 94.9 deg Dec: 6.6 deg\nGalactic lon: 188.4 deg, lat: 12.1 deg\nErr: 2.7 deg (1-sigma, statistical only)\n\nThe current systematic error of location is estimated to be several degrees\nwhich could be minimized by the ongoing calibration.\n\nThe GECAM light curve could be found here:\nhttp://twiki.ihep.ac.cn/pub/GECAM/GRBList/gecamb_lc_grd_21-22-11_65188203.png\n\nThe GECAM preliminary location could be found here:\nhttp://twiki.ihep.ac.cn/pub/GECAM/GRBList/gecamb_skymap_65188203_V01.png\n\nBased on the light curve, spectral hardness and location, we suggest that\nthis burst is likely from a galactic source. We note that 4U 0614+09 lies\nwithin the location error which could produce such an X-ray burst.\nHowever, the GRB nature could not be ruled out yet.\n\nAs the detailed science data are downloaded, all analyses would be improved.\n\nPlease note that all GECAM results here are preliminary. The final analysis\nwill be published in journal papers or GECAM online catalog.\n\nGravitational wave high-energy Electromagnetic Counterpart All-sky Monitor\n(GECAM) mission consists of two small satellites (GECAM-A and GECAM-B) in\nLow Earth Orbit (600 km, 29 deg), launched on Dec 10, 2020 (Beijing Time),\nwhich was funded by the Chinese Academy of Sciences (CAS).",
  "circularId": 29350,
  "createdOn": 1611499982000,
  "email": "xiongsl@ihep.ac.cn",
  "subject": "GECAM detection of a burst possibly from the X-ray burster 4U 0614+09 or GRB 210124A",
  "submitter": "Shaolin Xiong at IHEP  <xiongsl@ihep.ac.cn>",
  "eventId": "GRB 210124A"
}