J/MNRAS/493/3379 Comparison between GRB afterglows and AT2017gfo (Rossi+, 2020)
A comparison between short GRB afterglows and kilonova AT2017gfo:
shedding light on kilonovae properties.
Rossi A., Stratta G., Maiorano E., Spighi D., Masetti N., Palazzi E.,
Gardini A., Melandri A., Nicastro L., Pian E., Branchesi M., Dadina M.,
Testa V., Brocato E., Benetti S., Ciolfi R., Covino S., D'Elia V.,
Grado A., Izzo L., Perego A., Piranomonte S., Salvaterra R., Selsing J.,
Tomasella L., Yang S., Vergani D., Amati L., Stephen J.B.
<Mon. Not. R. Astron. Soc., 493, 3379-3397 (2020)>
=2020MNRAS.493.3379R 2020MNRAS.493.3379R (SIMBAD/NED BibCode)
ADC_Keywords: GRB ; Gravitational wave ; Photometry ; Optical ; Infrared
Keywords: gravitational waves - gamma-ray burst: general - gamma-ray bursts -
neutron star mergers - stars: magnetars
Abstract:
Multimessenger astronomy received a great boost following the
discovery of kilonova (KN) AT2017gfo, the optical counterpart of the
gravitational wave source GW170817 associated with the short gamma-ray
burst GRB 170817A. AT2017gfo was the first KN that could be
extensively monitored in time using both photometry and spectroscopy.
Previously, only few candidates have been observed against the glare
of short GRB afterglows. In this work, we aim to search the
fingerprints of AT2017gfo-like KN emissions in the optical/NIR light
curves of 39 short GRBs with known redshift. For the first time, our
results allow us to study separately the range of luminosity of the
blue and red components of AT2017gfo-like kilonovae in short GRBs. In
particular, the red component is similar in luminosity to AT2017gfo,
while the blue KN can be more than 10 times brighter. Finally, we
exclude a KN as luminous as AT2017gfo in GRBs 050509B and 061201.
Description:
The follow-up with VLT/X-Shooter of AT2017gfo is not only the first
spectroscopic observation of a KN, but it also provided the first
temporal sampling of this new class of sources. The 10 spectra,
described in Pian et al. (2017Natur.551...67P 2017Natur.551...67P) and Smartt et al.
(2017Natur.551...75S 2017Natur.551...75S), were taken between ∼1.5 and ∼10.5d after the GW
trigger and have a coverage from UV to NIR bands.
At epochs earlier than the first spectrum (i.e. <1.5d after the GW
trigger), we have collected photometric observations from the works of
Tanvir et al. (2017ApJ...848L..27T 2017ApJ...848L..27T), Drout et al.
(2017Sci...358.1570D 2017Sci...358.1570D), Evans et al. (2017Sci...358.1565E 2017Sci...358.1565E), Covino et
al. (2017NatAs...1..791C 2017NatAs...1..791C), Coulter et al. (2017Sci...358.1556C 2017Sci...358.1556C), Troja
et al. (2017Natur.551...71T 2017Natur.551...71T), Pian et al. (2017Natur.551...67P 2017Natur.551...67P),
Cowperthwaite et al. (2017ApJ...848L..17C 2017ApJ...848L..17C); see also the Kilonova
Project: Guillochon et al. (2017ApJ...835...64G 2017ApJ...835...64G).
Our starting sample of short GRBs is that presented by Fong et al.
(2015ApJ...815..102F 2015ApJ...815..102F) which includes 87 short GRBs with optical and
NIR counterparts observed between 2004 November and 2015 March. We
considered only the 33 events that have a redshift determination. We
extended this sample by including six short GRBs with known redshift,
detected between 2015 March and 2019 June.
Objects:
---------------------------------------------------------------
RA (ICRS) DE Designation(s)
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13 09 48.08 -23 22 53.3 AT2017gfo = AT 2017gfo = DLT 17ck
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 66 284 Table with GRB and AT2017gfo luminosity ratios
tablea2.dat 129 764 Short GRBs with known redshift in addition to
Fong et al. (2015ApJ...815..102F 2015ApJ...815..102F)
tablea3.dat 23 165 Rest-frame light curves of AT2017gfo
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Name GRB name (YYMMDDA)
9- 13 F5.1 h Time Observation time
15- 18 A4 --- Band Spectral band
20 A1 --- l_LGRB Limit flag on LGRB
22- 28 F7.2 10+19W/Hz LGRB GRB luminosity
30- 35 F6.2 10+19W/Hz e_LGRB ? Error on LGRB
37- 41 F5.2 10+19W/Hz LKN AT2017gfo luminosity in the GRB rest-frame
filter
43 A1 --- l_LGRB/LKN Limit flag on LGRB/LKN
45- 53 F9.2 --- LGRB/LKN LGRB/LKN luminosity ratio
55- 59 F5.3 --- z Redshift
61- 66 F6.1 nm lambda Rest wavelength
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Byte-by-byte Description of file: tablea2.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Name GRB name (YYMMDDA)
9- 18 F10.5 h DT Time ΔT
20- 32 A13 --- Tel/Inst Telescope/Instrument used
34- 40 A7 --- Filter Filter used
42 A1 --- l_Mag Limit flag on Mag
44- 48 F5.2 mag Mag ? Magnitude on the indicated filter
50- 53 F4.2 mag e_Mag ? Error on Mag
55 A1 --- l_Flux Limit flag on Flux
57- 66 F10.5 uJy Flux ? Flux density
68- 76 F9.6 uJy e_Flux ? Error on Flux
78- 82 F5.3 mag Av ? Galactic extinction
84-129 A46 --- Ref Reference
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Byte-by-byte Description of file: tablea3.dat
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Bytes Format Units Label Explanations
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1- 5 F5.2 d Time Observation time
7- 14 E8.3 10-7W/Hz Lum Luminosity
16- 21 F6.2 mag Mag Absolute AB magnitude
23 A1 --- Filter Filter used
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 26-Apr-2023