Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done using the HEASARC data.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
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BAT GROUND-DETECTED GRB DATA PROCESSING REPORT
(This burst occurred during telescope slew)
Process Script Ver: batgrbproduct v2.46
Process Start Time: Tue Nov 11 08:47:39 EST 2014
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/GRB090418B
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Trigger: 00090078 Segment: 001
BAT Trigger Time: 261737965.0
UTC: 2009-04-18T08:59:20.331 [includes UTCF correction]
Where From?: Ground analysis (best_duration.txt)
NOTE: BAT trigger time for ground-detected burst during slew is the T100 start time.
Refined Position: [ source = BAT mosaic image ]
RA: 225.914157234555 Dec: 17.2304913823518 [deg; J2000]
{ 15h 03m 39.4s , +17d 13' 49.8" }
+/- 0.392204406676 [arcmin] (estimated 90% radius based on SNR)
SNR: 115.843500037
Angular difference between the analysis and refined position is Usage: arcmin
Partial Coding Fraction: Unavailable because the burst occurred during slew.
Duration
T90: 38. +/- 1.
Measured from: 3
to: 41 [s; relative to TRIGTIME]
T50: 16. +/- 1.
Measured from: 13
to: 29 [s; relative to TRIGTIME]
====== Table of the duration information =============================
Value tstart tstop
T100 89.000 0.000 89.000
T90 38.000 3.000 41.000
T50 16.000 13.000 29.000
Peak 1.000 15.000 16.000
====== Spectral Analysis Summary =====================================
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^{Ph_index}
Ph_90err : 90% error of the photon index
Epeak : Epeak in keV
Epeak_90err: 90% error of Epeak
Norm : normalization at 50 keV in both the PL model and CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedo
=== Time-averaged spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.684 -0.031 0.031 - - - 2.00e-02 -3.14e-04 3.14e-04 41.620 57
CPL -1.553 -0.121 0.124 200.939 -69.125 4834.961 2.28e-02 -2.46e-03 2.86e-03 38.220 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: CPL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.463 -0.063 0.062 - - - 8.50e-02 -3.11e-03 3.11e-03 68.210 57
CPL -0.955 -0.259 0.275 110.317 -21.388 57.482 1.48e-01 -3.58e-02 5.07e-02 56.370 56
=== Fluence/Peak Flux Summary ===
Model Band1 Band2 Band3 Band4 Band5 Total
15-25 25-50 50-100 100-350 15-150 15-350 keV
Fluence PL 2.71e-06 4.45e-06 5.54e-06 1.37e-05 1.65e-05 2.64e-05 erg/cm2
90%_error_low -9.29e-08 -8.81e-08 -9.92e-08 -5.74e-07 -2.57e-07 -6.04e-07 erg/cm2
90%_error_hi 9.44e-08 8.79e-08 9.91e-08 5.91e-07 2.57e-07 6.16e-07 erg/cm2
Peak flux PL 3.38e+00 3.47e+00 2.52e+00 2.93e+00 1.05e+01 1.23e+01 ph/cm2/s
90%_error_low -2.23e-01 -1.43e-01 -1.11e-01 -2.57e-01 -4.02e-01 -4.50e-01 ph/cm2/s
90%_error_hi 2.28e-01 1.42e-01 1.10e-01 2.72e-01 4.02e-01 4.50e-01 ph/cm2/s
Fluence CPL 2.60e-06 4.46e-06 5.61e-06 1.18e-05 1.64e-05 2.45e-05 erg/cm2
90%_error_low -1.30e-07 -8.97e-08 -1.17e-07 -1.50e-06 -2.85e-07 -1.54e-06 erg/cm2
90%_error_hi 1.32e-07 8.96e-08 1.18e-07 1.76e-06 2.84e-07 1.79e-06 erg/cm2
Peak flux CPL 3.02e+00 3.60e+00 2.66e+00 1.80e+00 1.03e+01 1.11e+01 ph/cm2/s
90%_error_low -2.76e-01 -1.60e-01 -1.32e-01 -3.79e-01 -4.19e-01 -5.84e-01 ph/cm2/s
90%_error_hi 2.82e-01 1.62e-01 1.34e-01 4.94e-01 4.19e-01 6.48e-01 ph/cm2/s
======================================================================
Special notes of this burst