TITLE: GCN CIRCULAR NUMBER: 24389 SUBJECT: LIGO/Virgo S190503bf: Insight-HXMT/HE observation DATE: 19/05/04 14:04:15 GMT FROM: QiBin Yi at IHEP, HXMT Q. B. Yi, Q. Luo, C. Cai, S. Xiao, C. K. Li, X. B. Li, G. Li, J. Y. Liao, 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: Insight-HXMT was taking data normally around the GW trigger time(T0=2019-05-03 18:54:04 UTC). However, at T0 only about 0.01% of the LIGO localization region was covered by the Insight-HXMT without occultation by the Earth. Thus we cannot set upper limit on the impulsive emission for this GW event. Insight-HXMT is the first Chinese space X-ray telescope, which was fundedjointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information could be found at: http://www.hxmt.org.