J/ApJ/774/157 Swift GRBs with X-ray afterglows and z<9.5 (Dainotti+, 2013)
Determination of the intrinsic luminosity time correlation in the X-ray
afterglows of gamma-ray bursts.
Dainotti M.G., Petrosian V., Singal J., Ostrowski M.
<Astrophys. J., 774, 157 (2013)>
=2013ApJ...774..157D 2013ApJ...774..157D
ADC_Keywords: Gamma rays ; X-ray sources ; Redshifts
Keywords: cosmological parameters; gamma-ray burst: general;
radiation mechanisms: non-thermal
Abstract:
Gamma-ray bursts (GRBs), which have been observed up to redshifts
z∼9.5, can be good probes of the early universe and have the potential
to test cosmological models. Dainotti's analysis of GRB Swift
afterglow light curves with known redshifts and a definite X-ray
plateau shows an anti-correlation between the rest-frame time when the
plateau ends (the plateau end time) and the calculated luminosity at
that time (or approximately an anti-correlation between plateau
duration and luminosity) (Dainotti+ 2008MNRAS.391L..79D 2008MNRAS.391L..79D,
2010ApJ...722L.215D 2010ApJ...722L.215D). Here, we present an update of this correlation
with a larger data sample of 101 GRBs with good light curves. Since
some of this correlation could result from the redshift dependences of
these intrinsic parameters, namely, their cosmological evolution, we
use the Efron-Petrosian method to reveal the intrinsic nature of this
correlation. We find that a substantial part of the correlation is
intrinsic and describe how we recover it and how this can be used to
constrain physical models of the plateau emission, the origin of which
is still unknown. The present result could help to clarify the debated
nature of the plateau emission.
Description:
We have analyzed the sample of all GRB X-ray afterglows with known
redshifts detected by Swift from 2005 January up to 2011 May for which
the light curves include early X-ray data and therefore can be fitted
by the model of Willingale+, 2007ApJ...662.1093W 2007ApJ...662.1093W
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 70 101 Fitting parameters of the analyzed GRB
X-ray afterglows
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See also:
J/ApJS/209/20 : Swift GRB catalog with X-ray data (Grupe+, 2013)
J/MNRAS/428/729 : GRB Swift X-ray light curves analysis (Margutti+, 2013)
J/other/Sci/338.1445 : Relativistic jets from BH systems (Nemmen+, 2012)
J/A+A/547/A57 : Swift X-ray Telescope Cluster Survey (Tundo+, 2012)
J/A+A/528/A122 : SwiftFT catalog (Puccetti+, 2011)
J/MNRAS/418/2202 : Analysis of γ-ray bursts (Dainotti+, 2011)
J/ApJS/195/2 : The second Swift BAT GRB catalog (BAT2) (Sakamoto+, 2011)
J/ApJ/711/495 : Durations of Swift/BAT GRBs (Butler+, 2010)
J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)
J/ApJ/609/935 : Gamma-ray burst formation rate (Yonetoku+, 2004)
http://www.mpe.mpg.de/~jcg/grbgen.html : List of GRBs with coordinates; and
redshifts if any
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- GRB GRB identifier
9- 14 F6.4 --- z [0.03/9.4] Redshift
16- 23 E8.3 mW/m2 Fx Observed X-ray flux; erg/s/cm2
25- 32 E8.3 mW/m2 e_Fx Uncertainty in Fx
34- 37 F4.2 --- beta [0.3/3.6] Afterglow spectral index β (1)
39- 44 F6.4 --- e_beta [0.02/4.3] Uncertainty in beta
46- 49 F4.2 [s] logTa [1.6/5.3] Log of characteristic rest frame
time of initial X-ray decay (1)
51- 54 F4.2 [s] e_logTa [0.01/0.59] Uncertainty in logTa
56- 60 F5.2 [10-7W] logLx [42.5/50.2] Log of X-ray source luminosity
at Ta (0.3-10keV); erg/s (1)
62- 65 F4.2 [10-7W] e_logLx [0.02/1.61] Uncertainty in logLx
67- 70 A4 --- Class Classification: "long" duration or
"IC"=Intermediate class
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Note (1): modelisation of the rest-frame X-ray afterglow luminosity
(for t≥Ta) with
LX = 4πD2(z) FX (1+z)β-1
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 06-Mar-2015