GRB 200219C
GCN Circular 27298
Subject
GRB 200219C: VLA Detection
Date
2020-03-03T03:29:34Z (6 years ago)
From
Virginia Cunningham at U of MD <vcunning@astro.umd.edu>
V. Cunningham (UMD), S. B. Cenko (NASA GSFC), S. Vogel (UMD)
We observed the Fermi GBM/LAT GRB 200219C (The Fermi GBM Team,
GCN 27145; Dirirsa et al., GCN 27151; Hamburg et al., GCN 27155) at 6 GHz
with the Karl G. Jansky Very Large Array (VLA) on 2020 Feb 25 11:23:02 UTC
(5.48 days post GBM trigger). We report a preliminary flux density of ~658 uJy
at position:
RA (J2000): 17:30:02.295 +/- 0.011
Dec (J2000): +10:32:22.237 +/- 0.011
This is consistent with the position of the potential host galaxy (Xu
et al., GCN
27161), optical afterglow (Reva et al., GCN 27162; Blazek et al., GCN 27166),
and X-ray afterglow (Burrows et al., GCN 27157).
We thank the VLA staff for their assistance in completing these observations.
GCN Circular 27228
Subject
Konus-Wind observation of GRB 200219C
Date
2020-02-26T19:03:50Z (6 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:
The long-duration GRB 200219C
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 27145;
Hamburg et al., GCN Circ. 27155;
Fermi-LAT detection: Dirirsa et al., GCN Circ. 27151;
CALET-GBM detection: Sugita et al., GCN Circ. 27163)
triggered Konus-Wind at T0=86229.162 s UT (23:57:09.162).
The burst light curve shows a bright peak which starts at ~T0-3.4 s
and has a duration of ~9.8 s, followed by a weaker emission
seen up to ~T0+23 s. Total burst duration is ~27 s.
The emission is seen up to ~4 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200219_T86229
As observed by Konus-Wind, the burst
had a fluence of 1.87(-0.11,+0.13)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+3.488 s,
of 5.40(-1.08,+1.23)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+29.952 s)
is best fit in the 20 keV - 2 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.08(-0.12,+0.12)
and Ep = 209(-21,+27) keV (chi2 = 60/61 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.6
(chi2 = 60/60 dof).
The spectrum near the maximum count rate
(measured from T0+0.256 to T0+5.376 s)
is best fit in the 20 keV - 4 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.83(-0.10,+0.12),
the high energy photon index beta = -3.58(-6.42,+0.82),
the peak energy Ep = 234(-22,+20) keV
(chi2 = 62/75 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
GCN Circular 27180
Subject
GRB 200219C: Swift-XRT afterglow confirmation
Date
2020-02-24T21:22:36Z (6 years ago)
From
Valerio D'Elia at ASDC <valerio.delia@ssdc.asi.it>
V. D���Elia (SSDC) reports on behalf of the Swift-XRT team:
We provide an update on the XRT light curve evolution of the candidate X-ray afterglow of GRB 200219C (GCN Circ. 27157).
The XRT light curve now comprises data up to 260 ks from the Fermi trigger (GCN Circs. 27151 and 27155). There is a firm indication of fading with respect to the first observation, with a decay index of 0.8 (+0.4 -0.3). We thus confirm that this is indeed the afterglow of GRB 200219C.
The latest results can be viewed via: https://www.swift.ac.uk/xrt_curves/00020973/ <https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.swift.ac.uk%2Fxrt_curves%2F00020973%2F&data=02%7C01%7Cvalerio.delia%40ssdc.asi.it%7Ccbb05988e1604c1b0a9608d7b9502580%7Ccbfc58d4e60f468d8fe490676de085f7%7C0%7C0%7C637181626207379817&sdata=y0NsJNyq79oZqD4RZJb5be%2Fwwkz6UNNz%2B%2F3wajd%2Bs54%3D&reserved=0>
This circular is an official product of the Swift-XRT team.
GCN Circular 27166
Subject
GRB 200219C: OAJ afterglow confirmation
Date
2020-02-21T20:03:17Z (6 years ago)
From
Alexander Kann at IAA-CSIC <kann@iaa.es>
M. Blazek, D. A. Kann (both HETH/IAA-CSIC), A. de Ugarte Postigo
(HETH/IAA-CSIC, DARK/NBI), C. C. Thoene, J. F. Agui Fernandez (both
HETH/IAA-CSIC), N. Maicas, and J. L. Lamadrid (both CEFCA) report:
We observed the position of the Fermi GBM/LAT GRB 200219C (Fermi GBM
team, GCN #27145, Hamburg et al., GCN #27155, Dirirsa et al., GCN
#27151) with the Javalambre Observatory OAJ 80cm telescope in g'r'i'z',
obtaining 3 x 300 s exposures in g'r' each, and 5 x 180 s exposures in
i'z' each. Observations started on 2020-02-21, 03:17:55 UT. No
observations were obtained the night before as the LAT position came
only after twilight had started.
In the stacked r' image (midtime 1.14375 days after the GRB), we clearly
detect a source within the enhanced XRT error circle (Burrows et al.,
GCN #27157) for which we measure r'(AB) = 22.11 �� 0.13 mag against
PanSTARRS field stars.
We note this implies a decay compared with the afterglow discovery by
Reva et al. (GCN #27162) who find R ~ 21.72 �� 0.15 mag (AB) about six
hours earlier. It is still brighter than the PanSTARRS host galaxy
magnitude given by Xu et al. (GCN #27161) at r' = 22.70 �� 0.15 mag.
The relatively bright host galaxy may be indicative of a low-redshift
event. As the source is improving in visibility and will be observable
for several months to come, a search for associated supernova emission
may be worthwhile. Spectroscopy is encouraged.
GCN Circular 27163
Subject
GRB 200219C: CALET Gamma-Ray Burst Monitor detection
Date
2020-02-21T15:33:14Z (6 years ago)
From
Valentin Pal'shin at AGU <val@phys.aoyama.ac.jp>
S. Sugita, A. Yoshida, T. Sakamoto, V. Pal'shin (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 long GRB 200219C (Fermi GBM detection: Fermi GBM Team,
GCN Circ. 27145, Hamburg et al., GCN Circ. 27155;
Fermi-LAT detection: Dirirsa et al., GCN Circ. 27151