[vsnet-grb-info 25575] Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27675
SUBJECT: Insight-HXMT X-ray and hard X-ray detection of the double peaks of the Fast Radio Burst from SGR 1935+2154
DATE:    20/05/01 18:23:45 GMT
FROM:    Shaolin Xiong at IHEP  <xiongsl at ihep.ac.cn>

Zhang S.-N., Xiong S.-L., Li C.-K., Li X.-B., Tuo Y.-L., Ge M.-Y.,
Zhao X.-F., Xiao S., Jia S.-M., Nie J.-Y., Zhao H.-S., Luo Q., Li B.,
Cai C., Tan Y., Xue W.-C., Lu F.-J., Song L.-M., Liu C.-Z., Chen Y.,
Cao X.-L., Xu Y.-P., Li T.-P. (IHEP), Lin L. (BNU), Zhang B. (UNLV),
on behalf of the Insight-HXMT team:

Here we report a refined analysis of the Insight-HXMT light curves,
which have been corrected for data saturation and dead-time effects.
Insight-HXMT light curves could be found at:
http://newshxmt.ihep.ac.cn/images/grb/SGR1935_3rd_atel.png

The light curve in LE (1-10 keV) consists of two major bumps with a
separation time of about 0.2 s. The first major bump in LE seems
much brighter and wider than that in ME (10-30 keV) and HE (20-250 keV),
while the second major bump are very bright in all three telescopes
(HE, ME and LE), which was also detected by INTEGRAL (Atel #13685) and
Konus-Wind (GCN #27669, Atel #13688).
In addition, there is a minor soft bump in LE at the early phase of
this flare which is marginally seen in ME data and absent in HE data.

In HE and ME, there are two narrow peaks (14:34:24.4175 UT and
14:34:24.4475 UT) riding on the second major bump.
In LE, these two narrow peaks are also visible, although the first peak
is rather weak. Considering that the separation time between these two
narrow peaks (~30 ms) is almost the same as that of the radio ones
(~30 ms, Atel #13681), and that the apparent time lag between these two
peaks and radio peaks (~8.6 s) is in perfect agreement with
the calculated dispersion (8.63 s) between X-ray and radio
using the measured DM (332.81 pc/cc) by CHIME/FRB (Atel #13681),
we suggest that these two peaks are very likely the X-ray
and hard X-ray counterparts of the double-peaked radio burst
reported by CHIME/FRB (Atel #13681).