[vsnet-grb-info 28212] GRB 210619B: ASIM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  30315
SUBJECT: GRB 210619B: ASIM observation
DATE:    21/06/25 07:18:32 GMT
FROM:    Martino Marisaldi at U of Bergen, Norway  <martino.marisaldi at uib.no>

M. Marisaldi (University of Bergen), A. Mezentsev (University of Bergen), 
N. Østgaard (University of Bergen), V. Reglero (University of Valencia) 
and T. Neubert (DTU Space) report on behalf of the ASIM Team:

At 23:59:27.928 UT on 19 June 2021, the Atmosphere-Space Interactions Monitor (ASIM)
mission triggered on the long bright GRB 210619B 
(Swift detection: D’Avanzo et al., GCN Circ. 30261; GECAM detection: Zhao et al., GCN Circ. 30264;
Fermi-LAT detection: Axelsson et al., GCN Circ. 30270; Konus-Wind detection: Svinkin et al., GCN Circ. 30276; 
Fermi GBM detection: Poolakkil et al., GCN Circ. 30279; CALET detection: Kawakubo et al., GCN Circ. 30284; 
SPI-ACS/INTEGRAL detection: Minaev et al., GCN Circ. 30304)

Photon by photon data with <1 microsecond time resolution have been
collected for a time interval of five seconds.
As seen by the Modular X- and Gamma-Ray Sensor (MXGS) onboard ASIM
the burst consists of a single emission episode. 
The emission is detected in the MXGS High Energy Detector (HED), sensitive in the range 0.3 to >30 MeV.  
The MXGS Low Energy Detector (LED), sensitive in the range 0.05 to 0.4 MeV, 
was not active at trigger time.

ASIM is an ESA mission onboard the International Space Station dedicated to the 
observation of Terrestrial Gamma-ray Flashes (TGFs) and Transient Luminous Events (TLEs) 
operative since June 2018 (Neubert et al., Space Sci Rev (2019) 215:26 
https://doi.org/10.1007/s11214-019-0592-z <https://doi.org/10.1007/s11214-019-0592-z>  ). 
The payload includes the Modular X- and Gamma-Ray Sensor (MXGS) 
(Østgaard et al., Space Sci Rev (2019) 215:23 https://doi.org/10.1007/s11214-018-0573-7 <https://doi.org/10.1007/s11214-018-0573-7>  ), 
and the the Modular Multispectral Imaging Array  (MMIA) 
(Chanrion et al., Space Sci Rev (2019) 215:28 https://doi.org/10.1007/s11214-019-0593-y <https://doi.org/10.1007/s11214-019-0593-y>  ). 
The ASIM Science Data Centre (ASDC) website is https://asdc.space.dtu.dk/ <https://asdc.space.dtu.dk/>