GRB 210528A
GCN Circular 30090
Subject
GRB 210528A: Fermi GBM Final Real-time Localization
Date
2021-05-28T14:14:06Z (4 years ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
The Fermi GBM team reports the detection of a likely LONG GRB
At 14:03:46 UT on 28 May 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210528A (trigger 643903431.162588 / 210528586).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 134.1, Dec = -16.3 (J2000 degrees, equivalent to J2000 08h 56m, -16d 18'), with a statistical uncertainty of 1.9 degrees.
The angle from the Fermi LAT boresight is 55.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210528586/quicklook/glg_skymap_all_bn210528586.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210528586/quicklook/glg_healpix_all_bn210528586.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210528586/quicklook/glg_lc_medres34_bn210528586.gif
GCN Circular 30091
Subject
GRB 210528A: BALROG localization (Fermi Trigger 643903431 / GRB 210528586)
Date
2021-05-28T14:24:25Z (4 years ago)
From
Jochen Greiner at MPE,Garching <jcg@mpe.mpg.de>
F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
643903431 at 14:03:46 on 28 May 2021 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).
The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 137.1+/-2.2 deg
Decl.(2000.0) = -14.0+/-2.4 deg
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB210528586/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB210528586/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB210528586/json
GCN Circular 30093
Subject
Fermi GRB 210528A: Global MASTER-Net observations report
Date
2021-05-28T23:15:13Z (4 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin,
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov, D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),
D. Buckley
(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova
(Irkutsk State University, API),
A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko
(Blagoveschensk Educational State University)
MASTER-IAC robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) started inspect of the Fermi GRB 210528A ( Fermi GBM team, GCN 30090) errorbox 23846 sec after notice time and 23874 sec after trigger time at 2021-05-28 20:41:40 UT, with upper limit up to 18.1 mag. Observations started at twilight. The observations began at zenith distance = 61 deg. The sun altitude is -10.4 deg.
The galactic latitude b = 19 deg., longitude l = 244 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1623301
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
23904 | 2021-05-28 20:41:40 | MASTER-IAC | (09h 02m 44.74s , -13d 49m 49.9s) | C | 60 | 16.3 |
24064 | 2021-05-28 20:44:20 | MASTER-IAC | (09h 07m 35.44s , -15d 45m 51.5s) | C | 60 | 16.7 |
24224 | 2021-05-28 20:46:59 | MASTER-IAC | (09h 00m 12.10s , -15d 50m 05.1s) | C | 60 | 17.2 |
24224 | 2021-05-28 20:46:59 | MASTER-IAC | (08h 51m 50.12s , -15d 44m 39.9s) | C | 60 | 16.6 |
24463 | 2021-05-28 20:50:59 | MASTER-IAC | (08h 55m 21.79s , -13d 57m 05.7s) | C | 60 | 17.5 |
24463 | 2021-05-28 20:50:59 | MASTER-IAC | (08h 47m 03.96s , -13d 51m 40.4s) | C | 60 | 17.0 |
24623 | 2021-05-28 20:53:38 | MASTER-IAC | (09h 05m 43.99s , -17d 44m 47.2s) | C | 60 | 17.8 |
24623 | 2021-05-28 20:53:38 | MASTER-IAC | (08h 57m 16.72s , -17d 39m 23.2s) | C | 60 | 17.4 |
24863 | 2021-05-28 20:57:39 | MASTER-IAC | (09h 02m 46.24s , -13d 50m 39.8s) | C | 60 | 17.5 |
25423 | 2021-05-28 21:06:59 | MASTER-IAC | (09h 07m 34.43s , -15d 44m 11.1s) | C | 60 | 17.9 |
28711 | 2021-05-28 22:01:46 | MASTER-IAC | (09h 00m 07.99s , -15d 52m 31.3s) | C | 60 | 18.1 |
28950 | 2021-05-28 22:05:46 | MASTER-IAC | (08h 55m 24.26s , -13d 58m 30.1s) | C | 60 | 18.1 |
29110 | 2021-05-28 22:08:26 | MASTER-IAC | (09h 05m 38.03s , -17d 45m 24.2s) | C | 60 | 18.1 |
29670 | 2021-05-28 22:17:46 | MASTER-IAC | (09h 00m 15.02s , -15d 50m 52.6s) | C | 60 | 18.0 |
29910 | 2021-05-28 22:21:45 | MASTER-IAC | (08h 55m 27.00s , -13d 57m 44.5s) | C | 60 | 17.9 |
30070 | 2021-05-28 22:24:25 | MASTER-IAC | (09h 05m 44.96s , -17d 46m 24.8s) | C | 60 | 18.0 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 30098
Subject
GRB 210528A: AstroSat CZTI detection
Date
2021-05-29T14:46:52Z (4 years ago)
From
Gaurav Waratkar at IIT,Bombay <gauravwaratkar@iitb.ac.in>
P. Sawant (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), S. Gupta
(IUCAA), V. Bhalerao (IITB), D. Bhattacharya (IUCAA), A. R. Rao
(IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat
CZTI collaboration:
Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al,
2020, arxiv:2011.07067) showed detection of a short GRB 210528A, which
was also detected by Fermi-GBM (GCN #30090).
The source was clearly detected in the 20 - 200 keV energy range. The
light curve showed multiple peaks of emission with the strongest peak at
2021-05-28 14:03:45.5 UT. The measured peak count rate associated with
the burst is 682 (+186, -164) cts/s above the background in the combined
data of all four quadrants, with a total of 307 (+69, -65) cts. The
local mean background count rate was 547 (+9, -11) cts/s. Using
cumulative rates, we measure a T90 of 0.89 (+0.2, -0.3) s.
It was also clearly detected in the CsI anticoincidence (Veto) detector
in the 100 - 500 keV energy range.
CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC
and PRL. The Indian Space Research Organisation funded, managed and
facilitated the project.
Links:
------
[1] http://astrosat.iucaa.in/czti/?q=grb
GCN Circular 30099
Subject
GRB 210528A: Fermi GBM detection
Date
2021-05-29T15:34:40Z (4 years ago)
From
Peter Veres at UAH <veresp@gmail.com>
P. Veres and C. Meegan (both UAH)
report on behalf of the Fermi GBM Team:
"At 14:03:46.16 UT on 28 May 2021, the Fermi Gamma-Ray Burst Monitor
(GBM) triggered and located GRB 210528A (trigger 643903431 /
210528586).
The on-ground calculated location, using the GBM trigger data, is
reported in GCN #30090.
The GBM light curve consists of a strong pulse with some overlapping
structure and a duration (T90) of about 1 s (50-300 keV). The
time-averaged spectrum from T0-0.3 s to T0+1.3 s is
best fit by a power law function with an exponential high-energy
cutoff. The power law index is -0.47 +/- 0.06 and the cutoff energy,
parameterized as Epeak, is 210 +/- 9 keV.
The event fluence (10-1000 keV) in this time interval is (3.90 +/-
0.12)E-6 erg/cm^2. The 64ms peak photon flux measured starting from T0
+ 0.256 s in the 10-1000 keV band is 31.7 +/- 2.0 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"