TITLE: GCN CIRCULAR NUMBER: 31236 SUBJECT: GRB 211211A: Insight-HXMT/HE detection DATE: 21/12/16 06:44:10 GMT FROM: Y Q Zhang at IHEP Y. Q. Zhang, S. L. Xiong, X. B. Li, C. Cai, Q. Luo, S. Xiao, J. C. Liu, W. C. Xue, Q. B. Yi, C. Zheng,Y. Huang, C. K. Li, G. Li, J. Y. Liao, X. Y. Song, S. L. Xiong, C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, M. Wu, Y. P. Xu, S. N. Zhang (IHEP), report on behalf of the Insight-HXMT team: At 2021-12-11T13:09:59.500 (T0), Insight-HXMT/HE detected GRB 211211A (trigger ID: HEB211211548) in a routine search of the data, which also triggered Fermi/GBM (Fermi GBM Team, GCN #31201), Swift/BAT (D'Ai A. et al., GCN #31202), CALET (Tamura T. et al., GCN #31226) and INTEGRAL/SPI-ACS (Minaev P. et al., GCN #31230) URL_LC: http://twiki.ihep.ac.cn/pub/HXMT/GRBList/HEB211211548_lc.jpg It should be noted that there is a significant saturation effect (data loss) during bright parts of this GRB in HXMT. All measurements above are made with the CsI detectors operating in the regular mode with the energy range of about 80-800 keV (deposited energy). Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed inside of the telescope. Insight-HXMT is the first Chinese space X-ray telescope, which was funded jointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information about it could be found at: http://www.hxmt.org.