[vsnet-grb-info 27043] IceCube-201221A: Upper limits from Insight-HXMT/HE observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29146
SUBJECT: IceCube-201221A: Upper limits from Insight-HXMT/HE observations
DATE:    20/12/23 11:31:02 GMT
FROM:    Ce Cai at IHEP  <caice at ihep.ac.cn>

C. Cai, C. Zheng, J. C. Liu, Q. Luo, S. Xiao, 
W. C. Xue, Q. B. Yi, Y. Q. Zhang, Y. Huang, C. K. Li, 
G. Li, X. B. 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:

Insight-HXMT was taking data normally around the trigger time
(T0=2020-12-21T12:36:53.00 UTC) of this high-energy neutrino event 
(GCN #29102), which was monitored by Insight-HXMT without any 
occultation by the Earth.

There is no significant excess event (SNR > 3 sigma) 
found in the search of the Insight-HXMT/HE raw light curve
(within T0 +/- 100 s).

Assuming the counterpart GRB with three typical GRB Band spectral 
models, two typical duration timescales(1 s, 10 s) coming from the position
of this neutrino event, the 5-sigma upper-limits fluence 
(0.2 - 5 MeV, incident energy) are reported below:

Band model 1 (alpha=-1.9, beta=-3.7, Ep=70 keV):
1s:  3.9e-08 erg cm^-2   
10s: 2.4-07 erg cm^-2 

Band model 2 (alpha=-1.0, beta=-2.3, Ep=230 keV):
1s:  6.8e-08 erg cm^-2   
10s: 3.6e-07 erg cm^-2

Band model 3 (alpha=-0.0, beta=-1.5, Ep=1000 keV):
1s:  2.0e-07 erg cm^-2  
10s: 1.1e-06 erg cm^-2 

Further analysis will be reported in the following circulars.

All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (record 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 could be found at: http://www.hxmt.org.