J/ApJS/216/32 Localizations of GRBs with Fermi GBM (Connaughton+, 2015)
Localization of gamma-ray bursts using the Fermi Gamma-ray Burst Monitor.
Connaughton V., Briggs M.S., Goldstein A., Meegan C.A., Paciesas W.S.,
Preece R.D., Wilson-Hodge C.A., Gibby M.H., Greiner J., Gruber D.,
Jenke P., Kippen R.M., Pelassa V., Xiong S., Yu H.-F., Bhat P.N.,
Burgess J.M., Byrne D., Fitzpatrick G., Foley S., Giles M.M., Guiriec S.,
van der Horst A.J., von Kienlin A., McBreen S., McGlynn S., Tierney D.,
Zhang B.-B.
<Astrophys. J. Suppl. Ser., 216, 32 (2015)>
=2015ApJS..216...32C 2015ApJS..216...32C
ADC_Keywords: Gamma rays
Keywords: gamma-ray burst: general; techniques: miscellaneous
Abstract:
The Fermi Gamma-ray Burst Monitor (GBM) has detected over 1400
gamma-ray bursts (GRBs) since it began science operations in 2008
July. We use a subset of over 300 GRBs localized by instruments such
as Swift, the Fermi Large Area Telescope, INTEGRAL, and MAXI, or
through triangulations from the InterPlanetary Network, to analyze the
accuracy of GBM GRB localizations. We find that the reported
statistical uncertainties on GBM localizations, which can be as small
as 1°, underestimate the distance of the GBM positions to the true
GRB locations and we attribute this to systematic uncertainties. The
distribution of systematic uncertainties is well represented (68%
confidence level) by a 3.°7 Gaussian with a non-Gaussian tail that
contains about 10% of GBM-detected GRBs and extends to approximately
14°. A more complex model suggests that there is a dependence of
the systematic uncertainty on the position of the GRB in spacecraft
coordinates, with GRBs in the quadrants on the Y axis better localized
than those on the X axis.
Description:
Between 2008 July and 2013 May, GBM triggered on 203 GRBs that were
well-localized by other instruments or by the IPN, with location
uncertainties (68% confidence level) smaller than 1°. These 203
reference locations are listed in Table 9.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table9.dat 142 203 203 reference locations for GRBs that were also
detected by GBM and which we use to assess
the accuracy of GBM locations
table10.dat 140 134 134 locations for GRBs that were also
triangulated by IPN
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See also:
J/ApJS/211/13 : The second Fermi/GBM GRB catalog (4yr) (von Kienlin+, 2014)
J/ApJS/207/39 : IPN supplement to the Fermi GBM (Hurley+, 2013)
J/ApJS/207/38 : IPN localizations of Konus short GRBs (Pal'shin+, 2013)
J/ApJ/763/15 : Fermi GRB analysis. III. T90 distributions (Qin+, 2013)
J/MNRAS/431/3608 : BeppoSAX/GRBM and Fermi/GBM long GRBs (Dichiara+, 2013)
J/ApJ/760/12 : LIGO/Virgo gravitational-wave (GW) bursts (Abadie+, 2012)
J/ApJ/756/112 : Fermi/GBM GRB time-resolved spectral analysis (Lu+, 2012)
J/ApJ/754/121 : GRBs from Fermi/GBM and LAT (The Fermi Team, 2012)
J/ApJS/199/18 : The Fermi GBM catalog (Paciesas+, 2012)
J/A+A/530/A21 : Spectral properties of 438 GRBs (Nava+, 2011)
J/A+A/525/A53 : GBM parameters for detected FERMI bursts (Guetta+, 2011)
http://fermi.gsfc.nasa.gov/ssc/data/access/gbm : Fermi GBM online data
http://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html : Fermi GMB burst
online catalog
Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- TID Burst identifier (YYMMDDNN)
11- 13 A3 --- --- [GRB]
15- 21 A7 --- GRB Common name (YYMMDDA)
23- 33 A11 "h:m:s" Time UT trigger time
35- 39 F5.1 deg RA1deg ? First on board Flight Software (FSW)
Right Ascension (J2000) (1)
41- 45 F5.1 deg DE1deg ? First on board Flight Software (FSW)
Declination (J2000) (1)
47- 50 F4.1 deg ePos1 ? First FSW position error
52- 56 F5.1 deg RA2deg ? Last on board Flight Software (FSW)
Right Ascension (J2000) (1)
58- 62 F5.1 deg DE2deg ? Last on board Flight Software (FSW)
Declination (J2000) (1)
64- 67 F4.1 deg ePos2 ? Last FSW position error
69- 73 F5.1 deg RA3deg ? Ground auto Right Ascension (J2000) (1)
75- 79 F5.1 deg DE3deg ? Ground auto Declination (J2000) (1)
81- 84 F4.1 deg ePos3 ? Ground auto position error
86- 90 F5.1 deg RAdeg H.i.t.L Right Ascension (J2000) (1) (G1)
92- 96 F5.1 deg DEdeg H.i.t.L Declination (J2000) (1) (G1)
98-101 F4.1 deg ePos H.i.t.L position error (G1)
103-107 F5.1 deg RA4deg Reference Right Ascension (J2000) (1)
109-113 F5.1 deg DE4deg Reference Declination (J2000) (1)
115-132 A18 --- Aut First author's name of the reference
134-136 A3 --- --- [GCN]
138-142 I5 --- GCN [859/14842] GCN number of the reference
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Note (1): These locations come from Swift BAT, Swift XRT,
Fermi-LAT, INTEGRAL, MAXI, Super-AGILE, and the IPN.
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Byte-by-byte Description of file: table10.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- TID Burst identifier (YYMMDDNN)
11 A1 --- f_TID [1] 2 intersecting arcs (1)
13- 15 A3 --- --- [GRB]
17- 23 A7 --- GRB Common name (YYMMDDA)
25- 35 A11 "h:m:s" Time UT trigger time
37- 42 F6.2 deg RAIdeg ? IPN annulus Right Ascension (J2000)
44 A1 --- f_RAIdeg [1] Flag on IRAdeg (1)
46- 51 F6.2 deg DEIdeg ? IPN annulus Declination (J2000)
53 A1 --- f_DEIdeg [1] Flag on IDEdeg (1)
55- 61 F7.4 deg ePosI ? IPN annulus position error, or second arc (1)
63 A1 --- f_ePosI [1] Flag on e_IPNpos (1)
65- 70 F6.4 deg IWidth ? IPN annulus width, or second arc (1)
72 A1 --- f_IWidth [1] Flag on IWidth (1)
74- 78 F5.1 deg RA1deg ? First on board Flight Software (FSW)
Right Ascension (J2000)
80- 84 F5.1 deg DE1deg ? First on board Flight Software (FSW)
Declination (J2000)
86- 89 F4.1 deg ePos1 ? First FSW position error
91- 95 F5.1 deg RA2deg ? Last on board Flight Software (FSW)
Right Ascension (J2000)
97-101 F5.1 deg DE2deg ? Last on board Flight Software (FSW)
Declination (J2000)
103-106 F4.1 deg ePos2 ? Last FSW position error
108-112 F5.1 deg RA3deg ? Ground auto Right Ascension (J2000)
114-118 F5.1 deg DE3deg ? Ground auto Declination (J2000)
120-123 F4.1 deg ePos3 ? Ground auto position error
125-129 F5.1 deg RAdeg H.i.t.L Right Ascension (J2000) (G1)
131-135 F5.1 deg DEdeg H.i.t.L Declination (J2000) (G1)
137-140 F4.1 deg ePos H.i.t.L position error (G1)
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Note (1):
1 = These 9 bursts have 2 intersecting arcs, in which the columns are
as follows: RA, Dec, box side 1, box side 2.
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Global note:
Note (G1):
H.i.t.L. = Human in the Loop; refined ground locations using more data
and human judgment. See section 3.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 05-Mar-2015