{
  "bibcode": "2021GCN.30264....1Z",
  "body": "Y. Zhao, S. L. Xiong, Y. Huang, S. L. Xie, S. Xiao, C. Cai, J. C. Liu,\nC. Y. Li, Y. Q. Zhang, W. C. Xue, C. Zheng, Z. W. Guo, X. Y. Zhao,\nZ. H. An, C. Chen, G. Chen, W. Chen, M. Gao, K. Gong, D. Y. Guo, J. J. He,\nB. Li, C. Li, J. H. Li, Q. X. Li, X. B. Li, X. Q. Li, Y. G. Li, X. H. Liang,\nJ. Y. Liao, J. C. Liu, X. J. Liu, Y. Q. Liu, F. J. Lu, Q. Luo, X. Ma,\nG. Ou, W. X. Peng, R. Qiao, D. L. Shi, J. Y. Shi, L. M. Song,\nX. Y. Song, G. X. Sun, X. L. Sun, Y. L. Tuo, C. W. Wang, J. Z. Wang,\nP. Wang, X. Y. Wen, Y. B. Xu, Y. P. Xu, S. Yang, M. Yao, Q. B. Yi,\nB. X. Zhang, C. Y. Zhang, D. L. Zhang, Fan Zhang, Fei Zhang, H. M. Zhang,\nK. Zhang, P. Zhang, S. N. Zhang, Z. Zhang, S. Y. Zhao, S. J. Zheng,\nX. Zhou (IHEP), report on behalf of GECAM team:\n\nDuring the commissioning phase, GECAM-B was triggered in-flight by a long\nburst at 2021-06-20T00:00:00.950 UTC (denoted as T0), which was also\nobserved by Swift/BAT (GCN # 30261) and CALET/GBM (trigNum 1308182178).\nIts alert data was promptly downlinked to the ground through the short\nmessage service of BeiDou Navigation Satellite System (BDS). The time\nlatency of the first BeiDou message relative to the trigger time is about\n1 minute.\n\nAccording to the BDS alert data, this burst mainly consists of multiple\npulses with a duration of more than 60 s. An automatic on-ground\nlocalization was calculated using the light curves and spectrum. Although\nthe in-flight calibration of energy response and localization has not been\nfinalized yet, GECAM-B localized this burst to the following position (J2000): \nRa: 318.7 deg\nDec: 29.2 deg\nErr: 7.4 deg (1-sigma, statistical only)\nThe current systematic error of location is estimated to be several degrees \nwhich could be minimized by the ongoing calibration.\n\nThis GECAM location is consistent with that of Swift/BAT within the error.\n\nThe GECAM light curve could be found here:\nhttp://twiki.ihep.ac.cn/pub/GECAM/GRBList/gecamb_lc_grd_all_combine_77846400.png\n\nThe GECAM preliminary location could be found here: \nhttp://twiki.ihep.ac.cn/pub/GECAM/GRBList/gecamb_skymap_bdm_77846400_V01.png\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": 30264,
  "createdOn": 1624160405000,
  "email": "yizhao@ihep.ac.cn",
  "subject": "GECAM detection of GRB 210619B",
  "submitter": "Zhao Yi at POLAR  <yizhao@ihep.ac.cn>",
  "eventId": "GRB 210619B"
}