TY - JOUR
T1 - Multi-wavelength study of the luminous GRB 210619B observed with Fermi
and ASIM
AU - Caballero-García, M. D.
AU - Gupta, Rahul
AU - Pandey, S. B.
AU - Oates, S. R.
AU - Marisaldi, M.
AU - Ramsli, A.
AU - Hu, Y. -D.
AU - Castro-Tirado, A. J.
AU - Sánchez-Ramírez, R.
AU - Connell, P. H.
AU - Christiansen, F.
AU - Ror, A. Kumar
AU - Aryan, A.
AU - Bai, J. -M.
AU - Castro-Tirado, M. A.
AU - Fan, Y. -F.
AU - Fernández-García, E.
AU - Kumar, A.
AU - Lindanger, A.
AU - Mezentsev, A.
AU - Navarro-González, J.
AU - Neubert, T.
AU - Østgaard, N.
AU - Pérez-García, I.
AU - Reglero, V.
AU - Sarria, D.
AU - Sun, T. R.
AU - Xiong, D. -R.
AU - Yang, J.
AU - Yang, Y. -H.
AU - Zhang, B. -B.
PY - 2022
Y1 - 2022
N2 - We report on detailed multiwavelength observations and analysis of the
very bright and long GRB 210619B, detected by the Atmosphere-Space
Interactions Monitor installed on the International Space Station and
the Gamma-ray Burst Monitor (GBM) on-board the Fermi mission.
Our main goal is to understand the radiation mechanisms and jet
composition of GRB 210619B. With a measured redshift of z = 1.937, we find that GRB 210619B falls within the 10 most luminous bursts observed by Fermi
so far. The energy-resolved prompt emission light curve of GRB 210619B
exhibits an extremely bright hard emission pulse followed by
softer/longer emission pulses. The low-energy photon index (αpt)
values obtained using the time-resolved spectral analysis of the burst
suggest a transition between the thermal (during harder pulse) to
non-thermal (during softer pulse) outflow. We examine the correlation
between spectral parameters and find that both peak energy and αpt
exhibit the flux tracking pattern. The late time broad-band photometric
data set can be explained within the framework of the external forward
shock model with νm < νc < νx (where νm, νc, and νx
are the synchrotron peak, cooling-break, and X-ray frequencies,
respectively) spectral regime supporting a rarely observed hard electron
energy index (p < 2). We find moderate values of host extinction of E(B − V) =
0.14 ± 0.01 mag for the small magellanic cloud extinction law. In
addition, we also report late-time optical observations with the 10.4 m
Gran Telescopio de Canarias placing deep upper limits for the host
galaxy (z = 1.937), favouring a faint, dwarf host for the burst.
AB - We report on detailed multiwavelength observations and analysis of the
very bright and long GRB 210619B, detected by the Atmosphere-Space
Interactions Monitor installed on the International Space Station and
the Gamma-ray Burst Monitor (GBM) on-board the Fermi mission.
Our main goal is to understand the radiation mechanisms and jet
composition of GRB 210619B. With a measured redshift of z = 1.937, we find that GRB 210619B falls within the 10 most luminous bursts observed by Fermi
so far. The energy-resolved prompt emission light curve of GRB 210619B
exhibits an extremely bright hard emission pulse followed by
softer/longer emission pulses. The low-energy photon index (αpt)
values obtained using the time-resolved spectral analysis of the burst
suggest a transition between the thermal (during harder pulse) to
non-thermal (during softer pulse) outflow. We examine the correlation
between spectral parameters and find that both peak energy and αpt
exhibit the flux tracking pattern. The late time broad-band photometric
data set can be explained within the framework of the external forward
shock model with νm < νc < νx (where νm, νc, and νx
are the synchrotron peak, cooling-break, and X-ray frequencies,
respectively) spectral regime supporting a rarely observed hard electron
energy index (p < 2). We find moderate values of host extinction of E(B − V) =
0.14 ± 0.01 mag for the small magellanic cloud extinction law. In
addition, we also report late-time optical observations with the 10.4 m
Gran Telescopio de Canarias placing deep upper limits for the host
galaxy (z = 1.937), favouring a faint, dwarf host for the burst.
KW - Methods: data analysis
KW - Gamma-ray burst: general
KW - Gamma-ray burst: individual: GRB 210619B
U2 - 10.1093/mnras/stac3629
DO - 10.1093/mnras/stac3629
M3 - Journal article
SN - 0035-8711
VL - 519
SP - 3201
EP - 3226
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
ER -