GRB 190720A
GCN Circular 25123
Subject
GRB 190720A: Fermi GBM Final Real-time Localization
Date
2019-07-20T14:54:07Z (6 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 14:42:09 UT on 20 Jul 2019, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 190720A (trigger 585326534.78377 / 190720613).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 202.7, Dec = 41.8 (J2000 degrees, equivalent to J2000 13h 30m, 41d 47'), with a statistical uncertainty of 1.2 degrees.
The angle from the Fermi LAT boresight is 59.0 degrees.
The skymap can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190720613/quicklook/glg_skymap_all_bn190720613.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190720613/quicklook/glg_healpix_all_bn190720613.fit
The GBM light curve can be found here:
http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2019/bn190720613/quicklook/glg_lc_medres34_bn190720613.gif
GCN Circular 25124
Subject
GRB 190720A: BALROG localization (Fermi Trigger 585326534 / GRB 190720613)
Date
2019-07-20T15:17:17Z (6 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
585326534 at 14:42:09 on 20 July 2019 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) = 203.4+/-0.6 deg
Decl.(2000.0) = 42.7+/-0.5 deg
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB190720613/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB190720613/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB190720613/json
GCN Circular 25131
Subject
GRB 190720A: Fermi GBM detection
Date
2019-07-20T23:13:48Z (6 years ago)
From
C. Michelle Hui at MSFC/Fermi-GBM <cmhui.astro@gmail.com>
C. M. Hui (NASA-MSFC) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:
At 14:42:09.78 UT on 20 July 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190720A (trigger 585326534/190720613).
The on-ground calculated location, using the GBM trigger
data, is RA = 202.72 , DEC = +41.78 (J2000 degrees,
equivalent to 13h 30m, +41d 42.0'), with an uncertainty
of 1.16 degrees (radius, 1-sigma containment, statistical only;
there is additionally a systematic error which we have characterized
as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error
and a small tail suffering a larger than 10 deg systematic error
[Connaughton et al. 2015, ApJS, 216, 32] ).
The angle from the Fermi LAT boresight is 59.00 degrees.
The GBM light curve shows/consists of single peak
with a duration (T90) of about 6.1s (50-300 keV).
The time-averaged spectrum from T0-0.0s to T0+8.8s is
adequately fit by a Band function with Epeak = 182 +/- 6 keV,
alpha = -0.89 +/- 0.02, and beta = -2.21 +/- 0.04.
The event fluence (10-1000 keV) in this time interval is
(2.74 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.5s in the 10-1000 keV band is 48.2 +/- 0.5 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
<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/
GCN Circular 25139
Subject
IPN triangulation of GRB 190720A
Date
2019-07-22T22:53:38Z (6 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
K. Hurley, on behalf of the IPN,
I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,
D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,
A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team,
A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
and
W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:
The long-duration GRB 190720A
(Fermi-GBM detection: Fermi GBM Team, GCN Circ. 25123,
Hui and Meegan, GCN Circ. 25131;
BALROG localization: Kunzweiler et al., GCN Circ. 25124)
was detected by Fermi (GBM trigger 585326534), Konus-Wind,
INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND)
at about 52930 s UT (14:42:10).
We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
---------------------------------------------
RA(2000), deg Dec(2000), deg
---------------------------------------------
Center:
205.406 (13h 41m 37s) +41.340 (+41d 20' 25")
Corners:
205.272 (13h 41m 05s) +50.612 (+50d 36' 42")
205.533 (13h 42m 08s) +49.639 (+49d 38' 19")
204.561 (13h 38m 15s) +31.484 (+31d 29' 04")
204.550 (13h 38m 12s) +32.598 (+32d 35' 54")
---------------------------------------------
The error box area is about 2.4 sq. deg, and its maximum
dimension is 19.1 deg (the minimum one is 7.8 arcmin).
The Sun distance was about 71 deg.
This box may be improved.
This burst is spatially and temporally inconsistent with
LIGO/Virgo S190720a (LVC GCN Circ. 25115).
A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190720_T52927/IPN
The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.
GCN Circular 25148
Subject
GRB 190720A: CALET Gamma-Ray Burst Monitor detection
Date
2019-07-25T05:57:30Z (6 years ago)
From
Valentin Pal'shin at AGU <val@phys.aoyama.ac.jp>
Y. Kawakubo (LSU),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Ozawa, 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 long bright GRB 190720A (Fermi GBM detection: Hui and Meegan,
GCN Circ. 25131; BALROG localization: Kunzweiler et al., GCN Circ. 25124;
IPN triangulation: Hurley et al., GCN Circ. 25139) triggered the CALET
Gamma-ray Burst Monitor (CGBM) at 14:42:10.000 UTC on 20 July 2019.
The burst signal was seen by all CGBM detectors.
No real-time CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).
The burst light curve shows a single multi-peaked pulse which starts
at T-0.2 sec, peaks at 2.4 sec and ends at T+14.0 sec. The T90 and T50
durations measured by the SGM data are 5.9 +- 1.0 sec and 2.1 +- 0.2 sec
(40-1000 keV), respectively.
The ground processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1247668851/
The CALET data used in this analysis are provided by the Waseda CALET
Operation Center located at the Waseda University.