J/MNRAS/490/927 Bayesian Fermi-GBM short GRB spectral catalogue (Burgess+, 2019)
A Bayesian Fermi-GBM short GRB spectral catalogue.
Burgess J.M., Greiner J., Begue D., Berlato F.
<Mon. Not. R. Astron. Soc., 490, 927-946 (2019)>
=2019MNRAS.490..927B 2019MNRAS.490..927B (SIMBAD/NED BibCode)
ADC_Keywords: GRB ; Gamma rays
Keywords: methods: data analysis - catalogues - gamma-ray burst: general
Abstract:
Inspired by the confirmed detection of a short gamma-ray burst (GRB)
in association with a gravitational wave signal, we present the first
Bayesian Fermi-Gamma-ray Burst Monitor (GBM) short GRB spectral
catalogue. Both peak flux and time-resolved spectral results are
presented. Data are analysed with the proper Poisson likelihood
allowing us to provide statistically reliable results even for spectra
with few counts. All fits are validated with posterior predictive
checks. We find that nearly all spectra can be modelled with a cut-off
power law. Additionally, we release the full posterior distributions
and reduced data from our sample. Following our previous study, we
introduce three variability classes based on the observed light-curve
structure.
Description:
The Fermi Science Support Center (FSSC)
(https://fermi.gsfc.nasa.gov/ssc/) provides public data from the Fermi
mission including GBM burst data. Additionally, the GBM public GRB
burst catalogue provides up-to-date durations and background
selections for all triggers classified as GRBs since the beginning of
the mission.
Using these data bases, we selected all GRBs with a T90 duration
less than 7s and retrieved the time-tagged event (TTE) data, response
matrices, and background selections for detectors with a viewing angle
less than 60° from the reported source location. The time span of
this selection is from 2008 July 14 to 2017 August 18. GBM releases
response matrices in two forms. Some GRBs have responses for a single
time interval (RSP) and others have responses determined for multiple
time intervals to account for the slewing of the spacecraft (RSP2). If
RSP2 files are available, we utilize these over the RSP files.
However, the short durations of these GRBs means that there should be
little difference between the use of RSPs and RSP2s.
The original sample includes 543 GRBs before data reduction. Because
of issues with background selections and lack of significant signal,
some GRBs were removed from the sample resulting in 321 short GRBs and
525 time-resolved spectra. Table A1 lists the best-fitting model and
68 per cent credible regions for the parameters of the spectra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 87 525 The best-fitting model and 68 per cent credible
regions for the parameters of the spectra
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See also:
J/ApJS/223/28 : The third Fermi/GBM GRB catalog (6yr) (Bhat+, 2016)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name GRB name (bnYYMMDDddd)
13- 18 F6.3 s Tstart Time interval used for the model fit: start
time
20- 24 F5.3 s Tstop Time interval used for the model fit: end
time
26- 29 A4 --- Model Model used for the fit (1)
31- 36 F6.2 10-9W/m2 Flux Peak flux from best-fit
38- 43 F6.2 10-9W/m2 E_Flux Upper error on Flux (2)
45- 49 F5.2 10-9W/m2 e_Flux Lower error on Flux (2)
51- 57 F7.2 keV Ep Peak energy from best fit
59- 64 F6.2 keV E_Ep Upper error on Ep (2)
66- 71 F6.2 keV e_Ep Lower error on Ep (2)
73- 77 F5.2 --- alpha Low energy spectral index from best-fit
79- 82 F4.2 --- E_alpha Upper error on alpha (2)
84- 87 F4.2 --- e_alpha Lower error on alpha (2)
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Note (1): Model as follows:
Band = Band function (Band, Matteson & Ford 1993ApJ...413..281B 1993ApJ...413..281B;
Greiner et al. 1995A&A...302..121G 1995A&A...302..121G)
CPL = Cut-off power law (CPL) function
Note (2): 68 per cent credible regions for the parameters of the spectra
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 26-Jan-2023