TITLE:   GCN CIRCULAR
NUMBER:  30115
SUBJECT: GRB 210529A: GECAM detection
DATE:    21/06/03 01:08:14 GMT
FROM:    QiBin Yi at IHEP, HXMT  <yiqb@ihep.ac.cn>

Q. B. Yi, S. Xiao, S. L. Xiong, X. Y. Zhao, X. Y. Song, Y. Huang,
C. Cai, Y. Zhao, C. Y. Li, J. C. Liu, Y. Q. Zhang, W. C. Xue, C. Zheng,
Z. W. Guo, X. L. Zhao, B. X. Zhang, C. W. Wang, S. L. Xie,
P. Wang, X. B. Li, W. X. Peng, R. Qiao, J. Wang, H. S. Zhao,
Z. H. An, C. Chen, G. Chen, W. Chen, M. Gao, K. Gong, D. Y. Guo, J. J. He,
B. Li, C. Li, C. Y. Li, J. H. Li, Q. X. Li, X. Q. Li, Y. G. Li, X. H. Liang,
J. Y. Liao, J. C. Liu, X. J. Liu, Y. Q. Liu, F. J. Lu, Q. Luo, X. Ma,
G. Ou,  D. L. Shi, J. Y. Shi, L. M. Song, G. X. Sun, X. L. Sun, Y. L. Tuo,
J. Z. Wang, X. Y. Wen, Y. B. Xu, Y. P. Xu, S. Yang, M. Yao, B. X. Zhang,
C. Y. Zhang, D. L. Zhang, Fan Zhang, Fei Zhang, H. M. Zhang, K. Zhang,
P. Zhang, S. N. Zhang, Z. Zhang, S. Y. Zhao, S. J. Zheng, X. Zhou (IHEP),
report on behalf of GECAM team:

During the commissioning phase, GECAM-B triggered a long hard GRB,
GRB 210529A, at 2021-05-29T16:15:24.950 UTC (denoted as T0), 
which was also observed by Fermi/GBM (GCN #30100).

According to the GECAM-B light curves in about 8 keV-4 MeV, 
this burst mainly consists of multiple pulses with a duration of about 1.3s.

The GECAM light curve could be found here:
http://twiki.ihep.ac.cn/pub/GECAM/GRBList/multiLCvsE_tn210529_161524.png

GECAM-B localized this burst to the following position (J2000):
Ra: 40.4 deg
Dec: -12.9 deg
Err: 26.7 deg (1-sigma, statistical only)
The current systematic error of location is estimated to be several degrees
which could be minimized by the ongoing calibration. This position is 
consistent with the Fermi GBM team localization (GCN 30100) within the error.

Please note that all GECAM results here are preliminary. The final analysis
will be published in journal papers or GECAM online catalog.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission consists of two small satellites (GECAM-A and GECAM-B) in
Low Earth Orbit (600 km, 29 deg), launched on Dec 10, 2020 (Beijing Time),
which was funded by the Chinese Academy of Sciences (CAS).