GRB 200521A
GCN Circular 27815
Subject
GRB200521A: ASIM observation
Date
2020-05-25T09:18:56Z (5 years ago)
From
Martino Marisaldi at U of Bergen, Norway <martino.marisaldi@uib.no>
M. Marisaldi (University of Bergen), A. Mezentsev (University of Bergen),
N. ��stgaard (University of Bergen), V. Reglero (University of Valencia)
and T. Neubert (DTU Space) report on behalf of the ASIM Team:
At 12:16:39.798 UT on 21 May 2020, the Atmosphere-Space Interactions Monitor (ASIM)
mission triggered on the bright short hard GRB 200521A
(AGILE detection: Verrecchia et al., GCN Circ. 27776;
CALET-GBM detection: Yoshida et al., GCN Circ. 27777;
CGBM-SPI-ACS triangulation: Sakamoto et al., GCN Circ. 27790;
IPN triangulation: Svinkin et al., GCN Circ. 27795;
Konus-Wind detection: Svinkin et al., GCN Circ. 27796)
Photon by photon data with <1 microsecond time resolution have been
collected for a time interval of two seconds centered at the trigger time.
As seen by the Modular X- and Gamma-Ray Sensor (MXGS) onboard ASIM
the burst consists of a single bright peak about 300 ms in duration.
The emission is detected in the MXGS High Energy Detector (HED),
sensitive in the range 0.3 to >30 MeV.
Significant emission is observed up to several 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)
(��stgaard 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/>
GCN Circular 27796
Subject
Konus-Wind detection of short/hard GRB 200521A
Date
2020-05-23T22:45:12Z (5 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
D. Svinkin, S. Golenetskii, R.Aptekar, D. Frederiks, A. Ridnaia,
A. Lysenko, A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The short GRB 200521A
(AGILE detection: Verrecchia et al., GCN Circ. 27776;
CALET-GBM detection: Yoshida et al., GCN Circ. 27777;
CGBM-SPI-ACS triangulation: Sakamoto et al., GCN Circ. 27790;
IPN triangulation: Svinkin et al., GCN Circ. 27795)
triggered Konus-Wind (KW) at T0=44201.268 s UT (12:16:41.268).
The light curve of the burst shows a single pulse
with a total duration of ~0.3 s.
The emission is seen up to ~10 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200521_T44201/
As observed by Konus-Wind, the burst had
a fluence of (1.28 +/- 0.15)x10^-5 erg/cm^2 and
a 16-ms peak energy flux, measured from T0+0.080 s,
of (7.38 +/- 0.87)x10^-5 erg/cm^2/s
(both in the 20 keV - 10 MeV energy range).
The spectrum of the burst (measured from T0 to T0+0.256 s)
is well fitted in the 20 keV - 15 MeV range
by a cutoff power-law (CPL) function with the following model
parameters: the photon index alpha = -0.26(-0.16,+0.18),
and the peak energy Ep = 1358(-170,+196) keV, chi2 = 46/61 dof.
Fitting this spectrum with a GRB (Band) function yields
nearly the same alpha and Ep, and an upper limit on beta of -2.7.
All the quoted errors are estimated at the 90% confidence level.
All the presented results are preliminary.
GCN Circular 27795
Subject
IPN triangulation of GRB 200521A (short)
Date
2020-05-23T22:36:52Z (5 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,
K. Hurley, on behalf of the IPN,
A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
and
A. Ursi, N. Parmiggiani, F. Verrecchia, A. Bulgarelli,
A. Trois, M. Marisaldi, C. Pittori, M. Tavani, Y. Evangelista,
I. Donnarumma, M. Cardillo, G. Piano, G. Minervini, A. Argan,
F. Lucarelli, A. Zoli, V. Fioretti, F. Fuschino, M. Pilia,
F. Longo, A. Giuliani on behalf of the AGILE team, report:
The short-duration GRB 200521A
(AGILE detection: Verrecchia et al., GCN Circ. 27776