batgrbproduct Analysis for Trigger=317888
Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done of the amount of data for this trigger downloaded to date.
- 3) This page will be updated for up to 8 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.41
Process Start Time (local time): Fri Jul 25 18:17:38 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger317888/GCN5_download_cron
======================================================================
Trigger: 00317888 Segment: 000
BAT Trigger Time: 238674377.6 [s; MET]
Trigger Stop: 238674378.624 [s; MET]
UTC: 2008-07-25T10:26:14.632460 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 121.714820861025 Dec: -13.9900040898407 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.58
Image Trigger?: NO
Rate S/N Ratio: 21.9772609758359 [ if not an image trigger ]
Image S/N Ratio: 7.58
Flight Position: [ source = BAT ]
RA: 121.714820861025 Dec: -13.9900040898407 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 121.698459116905 Dec: -13.9843405648047 [deg; J2000]
{ 08h 06m 47.6s , -13d 59' 03.6" }
+/- 1.30383290781206 [arcmin] (estimated 90% radius based on SNR)
+/- 0.511254392873864 [arcmin] (formal 1-sigma fit error)
SNR: 20.8216724987517
Angular difference between Flight and Ground position is 1.011392 arcmin
Partial Coding Fraction: 0.4257812 [ including projection effects ]
Duration
T90: 119.552000015974 +/- 79.5798824699839
Measured from: -96.6879999935627
to: 22.8640000224113 [s; relative to TRIGTIME]
T50: 15.2319999933243 +/- 2.36107094189168
Measured from: -2.79999998211861
to: 12.4320000112057 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 3.19600000977516
to: 4.19600000977516 [s; relative to TRIGTIME]
Total Fluence
Measured from: -105.519999980927
to: 51.7280000150204 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.568202 1.893206 1.710426 0.426223
0.102929 0.103446 0.091419 0.079135 [error]
Peak 0.058762 0.085674 0.094639 0.015066
0.009223 0.009663 0.009004 0.007328 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
=== 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 Power-law 5.02e-07 9.21e-07 1.30e-06 3.85e-06 3.72e-06 6.56e-06 erg/cm2
Error 5.14e-08 5.59e-08 9.19e-08 6.01e-07 2.24e-07 6.61e-07 erg/cm2
Peak flux Power-law 6.74e-01 7.43e-01 5.84e-01 7.58e-01 2.28e+00 2.76e+00 ph/cm2/s
Error 1.36e-01 9.23e-02 7.61e-02 2.05e-01 2.59e-01 3.10e-01 ph/cm2/s
Fluence Cutoff-PL 4.92e-07 9.30e-07 1.31e-06 3.30e-06 3.69e-06 5.91e-06 erg/cm2
Error 6.17e-08 6.26e-08 9.76e-08 1.21e-06 1.81e-07 1.51e-06 erg/cm2
Peak flux Cutoff-PL 6.11e-01 7.68e-01 6.13e-01 4.86e-01 2.24e+00 2.48e+00 ph/cm2/s
Error 1.69e-01 1.04e-01 9.15e-02 2.93e-01 2.68e-01 4.52e-01 ph/cm2/s
Fluence Band 4.87e-07 9.26e-07 1.31e-06 3.31e-06 3.69e-06 5.87e-06 erg/cm2
Error 5.95e-08 6.25e-08 9.96e-08 1.21e-06 2.39e-07 1.24e-06 erg/cm2
Peak flux Band 6.12e-01 7.69e-01 6.12e-01 5.50e-01 2.24e+00 2.53e+00 ph/cm2/s
Error 1.27e-01 1.05e-01 7.07e-02 3.29e-01 2.63e-01 4.37e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.504 0.100 - - 2.49e-03 1.39e-04 43.483 57
CPL 1.357 0.287 230.1 5000.0 2.93e-03 0.00e+00 43.295 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.346 0.188 - - 1.90e-02 2.08e-03 47.608 57
CPL 0.903 0.727 133.3 5000.0 3.08e-02 2.94e-02 46.576 56
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^-{Ph_index} (minus sign is not included in the 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 PL model and at 1 keV in CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedom
=== T90/T50 calculation in the 50-300 keV band (BATSE band) using 64 ms lc ===
T90 in the 50-300 keV band: 28.480000 sec.
T50 in the 50-300 keV band: 9.728000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 157.248 -105.520 51.728
T90 119.552 -96.688 22.864
T50 15.232 -2.800 12.432
Peak 1.000 3.196 4.196
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
121.6985 -13.9843 0.0092 38.0 -134.7 5.9649 20.8 TRIG_00317888
------------------------------------------
Foreground time interval of the image:
-105.520 51.728 (delta_t = 157.248 [sec])
Background time interval of the image:
-239.600 -105.520 (delta_t = 134.080 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 4) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 5) Time of each bin is in the middle of the bin.
1 s binning
From T0-310 s to T0+310 s
From T100_start - 20 s to T100_end + 30 s
Full time interval
64 ms binning
Full time interval
From T100_start to T100_end
From T0-5 sec to T0+5 sec
16 ms binning
From T100_start-5 s to T100_start+5 s
8 ms binning
From T100_start-3 s to T100_start+3 s
2 ms binning
From T100_start-1 s to T100_start+1 s
SN=5 or 10 sec. binning (whichever binning is satisfied first)
SN=5 or 10 sec. binning (T < 200 sec)
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) For long bursts, a spectral fit of the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -105.520 sec. to 51.728 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.50369 ( -0.100202 0.100119 )
Norm@50keV : 2.493158E-03 ( -1.392593E-04 1.390278E-04) )
------------------------------------------------------------
Chi-Squared = 43.48288 using 59 PHA bins.
Reduced chi-squared = 0.7628576 for 57 degrees of freedom
Null hypothesis probability = 0.906
Photon flux (15-150 keV) in 157.2 sec: 0.311550 ( -0.018242 0.018303 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.71555e-06 ( -2.22642e-07 2.24434e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -105.520 sec. to 51.728 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.35702 ( -0.333259 0.241242 )
Epeak [keV] : 230.076 ( -230.066 9769.92 )
Norm@50keV : 2.927723E-03 ( )
------------------------------------------------------------
Chi-Squared = 43.29541 using 59 PHA bins.
Reduced chi-squared = 0.7731323 for 56 degrees of freedom
Null hypothesis probability = 0.893
Photon flux (15-150 keV) in 157.2 sec: 0.309828 ( -0.009141 0.018146 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.6926e-06 ( -2.38488e-07 1.24078e-07 ) ergs/cm2
Band function
Time interval is from -105.520 sec. to 51.728 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.05759 ( -8.94241 5.50713 )
beta : -1.52204 ( -8.47796 0.108385 )
Epeak [keV] : 59.3158 ( -59.2158 934.991 )
Norm@50keV : 5.118656E-03 ( -4.33931 190.274 )
------------------------------------------------------------
Chi-Squared = 42.79169 using 59 PHA bins.
Reduced chi-squared = 0.7780308 for 55 degrees of freedom
Null hypothesis probability = 0.885
Photon flux (15-150 keV) in 157.2 sec: 0.309822 ( -0.019126 0.019135 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.68959e-06 ( -2.39463e-07 2.37859e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 3.216 sec. to 4.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.34649 ( -0.188127 0.187782 )
Norm@50keV : 1.895727E-02 ( -2.081735E-03 2.078850E-03) )
------------------------------------------------------------
Chi-Squared = 47.60754 using 59 PHA bins.
Reduced chi-squared = 0.8352199 for 57 degrees of freedom
Null hypothesis probability = 0.808
Photon flux (15-150 keV) in 0.9600 sec: 2.28217 ( -0.25824 0.25883 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.77894e-07 ( -2.13696e-08 2.14973e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.216 sec. to 4.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.902884 ( -0.865684 0.588887 )
Epeak [keV] : 133.276 ( -133.266 9866.72 )
Norm@50keV : 3.081759E-02 ( -1.343184E-02 4.532205E-02) )
------------------------------------------------------------
Chi-Squared = 46.57554 using 59 PHA bins.
Reduced chi-squared = 0.8317061 for 56 degrees of freedom
Null hypothesis probability = 0.811
Photon flux (15-150 keV) in 0.9600 sec: 2.24012 ( -0.26868 0.26766 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.73916e-07 ( -2.27126e-08 2.26349e-08 ) ergs/cm2
Band function
Time interval is from 3.216 sec. to 4.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.906607 ( -9.09339 1.63269 )
beta : -1.91321 ( -8.08679 11.1652 )
Epeak [keV] : 142.714 ( -127.143 9872.76 )
Norm@50keV : 2.982346E-02 ( -1.443851E-02 811.875 )
------------------------------------------------------------
Chi-Squared = 46.61898 using 59 PHA bins.
Reduced chi-squared = 0.8476179 for 55 degrees of freedom
Null hypothesis probability = 0.782
Photon flux (15-150 keV) in 0.9600 sec: 2.23822 ( -0.25743 0.26873 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.73878e-07 ( -2.27875e-08 2.25264e-08 ) ergs/cm2
Plot creation:
Fri Jul 25 18:41:50 EDT 2008