Gamma-ray Burst 200521A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN Circular #27776
F. Verrecchia (SSDC, and INAF/OAR), A. Ursi (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, C. Casentini, G. Piano (INAF/IAPS), F. Lucarelli, C. Pittori (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari), F. Longo (Univ. Trieste, and INFN Trieste), report on behalf of the AGILE Team:
The AGILE satellite detected the short burst GRB 200521A that triggered the automatic AGILE Mini-CALorimeter (MCAL) GRB alert Notice (ID 512427408), published at: https://gcn.gsfc.nasa.gov/agile_mcal.html.
The event was detected by MCAL at T0 = 2020-05-21 12:16:40.00 +/- 0.01 (UT), and lasted about 0.16 s and released a total number of ~795 counts in the detector (in the 0.4-100 MeV energy range), above an average background rate of 771 counts / s. The event is also visible in the scientific ratemeters of the SuperAGILE (SA; 20-60 keV), Anti-Coincidence (AC; 80-200 keV), and MCAL (0.4-100 MeV) detectors.
The MCAL light curve can be found at: http://www.agilescienceapp.it/notices/GRB_067901-067901_517148200.741647.png .
The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.
GCN Circular #27777
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration:
The bright short hard GRB 200521A (AGILE/MCAL and ratemeters detection: Verrecchia et al., GCN Circ. 27776) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 12:16:40.803 UTC on 21 May 2020. The burst signal was seen by all CGBM detectors. Because of a problem in one of the ground alert processing script, the GCN notice was not distributed automatically for this event.
The burst light curve shows a bright pulse which starts at T-0.304 sec, peaks at -0.016 sec and ends at T+0.056 sec. The T90 and T50 durations measured by the SGM data are 0.240 +- 0.094 sec and 0.104 +- 0.018 sec (40-1000 keV), respectively.
The ground processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1274098167/
The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
GCN Circular #27790
T. Sakamoto, A. Yoshida, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration:
Using the CALET Gamma-Ray Burst Monitor (CGBM) event data and publicly available INTEGRAl-SPI-ACS light curve data we have triangulated the bright short hard GRB 200521A (AGILE/MCAL and ratemeters detection: Verrecchia et al., GCN Circ. 27776; CGBM detection: Yoshida et al., GCN Circ. 27777) to a preliminary CGBM-SPI-ACS annulus centered at RA(J2000)=86.570 deg (05h 46m 17s) Dec(J2000)= -34.390 deg (-34d 23' 24"), whose radius is 88.32(-1.63,+1.63) deg (3 sigma).
The CGBM response also suggests the burst source was in the FOV of the CGBM HXM detectors, i.e. within 60 deg from RA, Dec(J2000) = 112.49 deg, +5.67 deg (=the center of the FOV).
The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
The INTEGRAL-SPI-ACS data used in this analysis were obtained from the INTEGRAL data archive through http://isdc.unige.ch/~savchenk/spiacs-online/ maintained by Volodymyr Savchenko.
GCN Circular #27795
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; CALET-GBM detection: Yoshida et al., GCN Circ. 27777; CGBM-SPI-ACS triangulation: Sakamoto et al., GCN Circ. 27790) has been detected by AGILE (MCAL, SuperAGILE, Anti-Coincidence), CALET (GBM), Konus-Wind, and INTEGRAL (SPI-ACS), so far, at about 44201 s UT (12:16:41).
We have triangulated it to a preliminary, 3 sigma error box whose coordinates are:
```
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   169.531 (11h 18m 07s)  +7.222 ( +7d 13' 20")
  Corners:
   168.785 (11h 15m 08s)  +5.440 ( +5d 26' 23")
   170.087 (11h 20m 21s)  +9.279 ( +9d 16' 45")
   170.289 (11h 21m 09s)  +8.994 ( +8d 59' 37")
   168.987 (11h 15m 57s)  +5.152 ( +5d 09' 08")
  ---------------------------------------------
```
The error box area is 1.14 sq. deg, and its maximum dimension is 4.27 deg (the minimum one is 16.9 arcmin). The Sun distance was about 106 deg.
This box may be improved.
A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB200521_T44201/IPN/
The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.
GCN Circular #27796
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 #27815
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 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 ). 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 ), 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 ). The ASIM Science Data Centre (ASDC) website is https://asdc.space.dtu.dk/

Back to JG's homepage

Jochen Greiner, last update: 25-May-2020 [Disclaimer]