batgrbproduct Analysis for Trigger=317508
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): Mon Jul 21 16:53:44 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger317508/GCN5_download_cron
======================================================================
Trigger: 00317508 Segment: 000
BAT Trigger Time: 238328719.936 [s; MET]
Trigger Stop: 238328720.96 [s; MET]
UTC: 2008-07-21T10:25:16.978500 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 224.47075880868 Dec: -11.7121266536717 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.24
Image Trigger?: NO
Rate S/N Ratio: 142.337626789265 [ if not an image trigger ]
Image S/N Ratio: 10.24
Flight Position: [ source = BAT ]
RA: 224.47075880868 Dec: -11.7121266536717 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 224.482036535949 Dec: -11.7101727660219 [deg; J2000]
{ 14h 57m 55.7s , -11d 42' 36.6" }
+/- 1.25651374250043 [arcmin] (estimated 90% radius based on SNR)
+/- 0.406079086772701 [arcmin] (formal 1-sigma fit error)
SNR: 21.9508271636475
Angular difference between Flight and Ground position is 0.672869 arcmin
Partial Coding Fraction: 0.04394531 [ including projection effects ]
Duration
T90: 64 +/- 144
Measured from: -15.9359999895096
to: 48.0640000104904 [s; relative to TRIGTIME]
T50: 16 +/- 16
Measured from: -15.9359999895096
to: 0.0640000104904175 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 7.56400001049042
to: 8.56400001049042 [s; relative to TRIGTIME]
Total Fluence
Measured from: -15.9359999895096
to: 352.06400001049 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 3.981471 6.231152 7.280946 3.137147
0.275908 0.276275 0.269920 0.233850 [error]
Peak 1.952186 3.499244 4.372035 1.872554
0.164956 0.175490 0.179039 0.153270 [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 1.53e-06 3.34e-06 5.74e-06 2.28e-05 1.57e-05 3.34e-05 erg/cm2
Error 1.45e-07 1.87e-07 2.58e-07 2.42e-06 6.72e-07 2.49e-06 erg/cm2
Peak flux Power-law 1.60e+00 2.00e+00 1.82e+00 2.88e+00 6.42e+00 8.31e+00 ph/cm2/s
Error 1.69e-01 1.29e-01 8.92e-02 3.03e-01 3.38e-01 3.94e-01 ph/cm2/s
Fluence Cutoff-PL 1.53e-06 3.34e-06 5.75e-06 2.27e-05 1.57e-05 3.13e-05 erg/cm2
Error 1.45e-07 1.87e-07 2.59e-07 2.40e-06 6.73e-07 4.68e-06 erg/cm2
Peak flux Cutoff-PL 1.50e+00 2.01e+00 1.87e+00 2.44e+00 6.35e+00 7.83e+00 ph/cm2/s
Error 2.27e-01 1.32e-01 1.20e-01 4.60e-01 3.44e-01 8.83e-01 ph/cm2/s
Fluence Band 1.51e-06 3.33e-06 5.73e-06 2.26e-05 1.57e-05 3.19e-05 erg/cm2
Error 1.43e-07 1.86e-07 3.02e-07 4.56e-06 5.06e-07 4.62e-06 erg/cm2
Peak flux Band 1.50e+00 2.01e+00 1.87e+00 2.44e+00 6.35e+00 7.83e+00 ph/cm2/s
Error 2.28e-01 1.32e-01 1.22e-01 6.22e-01 3.54e-01 7.43e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.218 0.078 - - 4.23e-03 1.85e-04 37.699 57
CPL 1.161 0.202 933.3 0.0 4.46e-03 1.86e-04 37.749 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.138 0.084 - - 5.51e-02 2.71e-03 35.197 57
CPL 0.935 0.297 330.4 5000.0 6.67e-02 1.92e-02 34.109 0
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: 22.336000 sec.
T50 in the 50-300 keV band: 6.016000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 368.000 -15.936 352.064
T90 64.000 -15.936 48.064
T50 16.000 -15.936 0.064
Peak 1.000 7.564 8.564
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
224.4820 -11.7102 0.0088 56.5 3.2 18.3724 22.0 TRIG_00317508
------------------------------------------
Foreground time interval of the image:
-15.936 13.865 (delta_t = 29.801 [sec])
Background time interval of the image:
-239.936 -15.936 (delta_t = 224.000 [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 -15.936 sec. to 352.064 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.21833 ( -7.783222E-02 7.722855E-02) )
Norm@50keV : 4.232165E-03 ( -1.858072E-04 1.848410E-04) )
------------------------------------------------------------
Chi-Squared = 37.69888 using 59 PHA bins.
Reduced chi-squared = 0.6613838 for 57 degrees of freedom
Null hypothesis probability = 0.977
Photon flux (15-150 keV) in 368.0 sec: 0.498094 ( -0.024043 0.024165 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.57199e-05 ( -6.71821e-07 6.7263e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.936 sec. to 352.064 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.16141 ( -0.273026 0.130645 )
Epeak [keV] : 933.292 ( )
Norm@50keV : 4.462245E-03 ( -1.889039E-04 1.823469E-04) )
------------------------------------------------------------
Chi-Squared = 37.74925 using 59 PHA bins.
Reduced chi-squared = 0.6740938 for 56 degrees of freedom
Null hypothesis probability = 0.971
Photon flux (15-150 keV) in 368.0 sec: 0.497845 ( -0.024028 0.024153 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.57262e-05 ( -6.72189e-07 6.72962e-07 ) ergs/cm2
Band function
Time interval is from -15.936 sec. to 352.064 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.953898 ( -9.04610 5.95254 )
beta : -1.21835 ( -7.720399E-02 7.786334E-02) )
Epeak [keV] : 46.7969 ( -46.6969 9953.08 )
Norm@50keV : 8.072061E-03 ( -4.023080E-03 2077.80 )
------------------------------------------------------------
Chi-Squared = 37.69888 using 59 PHA bins.
Reduced chi-squared = 0.6854342 for 55 degrees of freedom
Null hypothesis probability = 0.964
Photon flux (15-150 keV) in 368.0 sec: 0.497142 ( -0.022004 0.020834 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.57079e-05 ( -3.41688e-07 6.71232e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.064 sec. to 16.064 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.13781 ( -8.413768E-02 8.321643E-02) )
Norm@50keV : 5.511266E-02 ( -2.713457E-03 2.702098E-03) )
------------------------------------------------------------
Chi-Squared = 35.19719 using 59 PHA bins.
Reduced chi-squared = 0.6174946 for 57 degrees of freedom
Null hypothesis probability = 0.990
Photon flux (15-150 keV) in 16.00 sec: 6.41816 ( -0.33768 0.33902 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.11128e-06 ( -4.38768e-07 4.39008e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.064 sec. to 16.064 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.935114 ( -0.350895 0.243470 )
Epeak [keV] : 330.363 ( -330.353 9669.64 )
Norm@50keV : 6.667646E-02 ( -1.341743E-02 2.506510E-02) )
------------------------------------------------------------
Chi-Squared = 34.10875 using 59 PHA bins.
but latest trial 1.17430 gives Chi-Squared = 1.70736
Reduced chi-squared = 0.6090849 for 56 degrees of freedom
Null hypothesis probability = 0.991
Photon flux (15-150 keV) in 16.00 sec: 6.35139 ( -0.35031 0.33776 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.08824e-06 ( -4.46224e-07 4.41424e-07 ) ergs/cm2
Band function
Time interval is from 0.064 sec. to 16.064 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.594569 ( -9.40543 3.87985 )
beta : -1.17633 ( -8.36135 0.565828 )
Epeak [keV] : 99.0251 ( -331.277 415.222 )
Norm@50keV : 0.113005 ( -1.335420E-02 2.514318E-02) )
------------------------------------------------------------
Chi-Squared = 34.53703 using 59 PHA bins.
Reduced chi-squared = 0.6279460 for 55 degrees of freedom
Null hypothesis probability = 0.986
Photon flux (15-150 keV) in 16.00 sec: 6.35087 ( -0.35231 0.35481 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.08003e-06 ( -4.44352e-07 4.43232e-07 ) ergs/cm2
Plot creation:
Mon Jul 21 17:24:03 EDT 2008