batgrbproduct Analysis for Trigger=317897
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 18:47:03 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger317897/GCN5_download_cron
======================================================================
Trigger: 00317897 Segment: 000
BAT Trigger Time: 238677853.568 [s; MET]
Trigger Stop: 238677853.824 [s; MET]
UTC: 2008-07-25T11:24:10.600360 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 299.588797225291 Dec: 35.1728248681439 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 7.07
Image Trigger?: NO
Rate S/N Ratio: 9 [ if not an image trigger ]
Image S/N Ratio: 7.07
Flight Position: [ source = BAT ]
RA: 299.588797225291 Dec: 35.1728248681439 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 299.670910971208 Dec: 35.2174383086978 [deg; J2000]
{ 19h 58m 41.0s , +35d 13' 02.8" }
+/- 3.32500528080309 [arcmin] (estimated 90% radius based on SNR)
+/- 1.86633452095451 [arcmin] (formal 1-sigma fit error)
SNR: 5.46639175023104
Angular difference between Flight and Ground position is 4.834805 arcmin
Partial Coding Fraction: 0.9765625 [ including projection effects ]
Duration
T90: 737.659999996424 +/- 50.3223151021831
Measured from: -59.7519999742508
to: 677.908000022173 [s; relative to TRIGTIME]
T50: 326.819999992847 +/- 29.2752045224475
Measured from: 132.936000019312
to: 459.756000012159 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 343.89200001955
to: 344.89200001955 [s; relative to TRIGTIME]
Total Fluence
Measured from: -164.503999978304
to: 698.404000014067 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 9.565011 11.268674 7.026071 1.298141
0.151438 0.150483 0.133099 0.117583 [error]
Peak 0.033475 0.048243 0.027341 0.006314
0.005654 0.005840 0.005009 0.004427 [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 2.89e-06 4.57e-06 5.43e-06 1.25e-05 1.65e-05 2.54e-05 erg/cm2
Error 1.24e-07 1.09e-07 1.49e-07 8.01e-07 3.53e-07 8.70e-07 erg/cm2
Peak flux Power-law 3.27e-01 3.05e-01 1.97e-01 1.96e-01 9.10e-01 1.02e+00 ph/cm2/s
Error 7.26e-02 4.47e-02 4.03e-02 7.81e-02 1.32e-01 1.53e-01 ph/cm2/s
Fluence Cutoff-PL 2.80e-06 4.60e-06 5.48e-06 1.03e-05 1.63e-05 2.31e-05 erg/cm2
Error 1.66e-07 1.16e-07 1.58e-07 2.36e-06 4.26e-07 2.85e-06 erg/cm2
Peak flux Cutoff-PL 2.80e-01 3.52e-01 2.00e-01 4.66e-02 8.68e-01 8.78e-01 ph/cm2/s
Error 8.72e-02 6.42e-02 4.89e-02 8.42e-02 1.38e-01 1.57e-01 ph/cm2/s
Fluence Band 2.67e-06 4.64e-06 5.40e-06 1.17e-05 1.62e-05 2.44e-05 erg/cm2
Error 1.64e-07 1.33e-07 1.57e-07 1.51e-06 4.17e-07 1.56e-06 erg/cm2
Peak flux Band 2.76e-01 3.55e-01 1.96e-01 8.24e-02 8.73e-01 9.08e-01 ph/cm2/s
Error 8.70e-02 6.50e-02 4.72e-02 9.32e-02 1.36e-01 1.72e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.751 0.043 - - 2.40e-03 5.03e-05 53.320 57
CPL 1.591 0.171 136.3 4953.3 2.85e-03 4.96e-04 51.443 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.632 0.247 - - 7.01e-03 1.12e-03 53.840 57
CPL 0.307 1.470 56.3 90.4 3.81e-02 1.61e-01 50.614 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 862.908 -164.504 698.404
T90 737.660 -59.752 677.908
T50 326.820 132.936 459.756
Peak 1.000 343.892 344.892
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
299.6709 +35.2174 0.0350 16.0 -139.0 1.2402 5.5 TRIG_00317897
------------------------------------------
Foreground time interval of the image:
-164.504 14.633 (delta_t = 179.137 [sec])
Background time interval of the image:
-239.568 -164.504 (delta_t = 75.064 [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
Multiple GTIs in the spectrum
tstart tstop
-164.504000 542.477500
660.432000 698.404000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.75053 ( -4.268384E-02 4.279160E-02) )
Norm@50keV : 2.404893E-03 ( -5.027489E-05 5.024602E-05) )
------------------------------------------------------------
Chi-Squared = 53.32008 using 59 PHA bins.
Reduced chi-squared = 0.9354400 for 57 degrees of freedom
Null hypothesis probability = 0.614
Photon flux (15-150 keV) in 745.0 sec: 0.325245 ( -0.007957 0.007998 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.65312e-05 ( -3.52162e-07 3.53502e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-164.504000 542.477500
660.432000 698.404000
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.59133 ( -0.159016 0.182107 )
Epeak [keV] : 136.293 ( -42.8238 9863.71 )
Norm@50keV : 2.849060E-03 ( -4.725326E-04 5.191802E-04) )
------------------------------------------------------------
Chi-Squared = 51.44287 using 59 PHA bins.
but latest trial 2.404120E-03 gives Chi-Squared = 1.86074
Reduced chi-squared = 0.9186228 for 56 degrees of freedom
Null hypothesis probability = 0.648
Photon flux (15-150 keV) in 745.0 sec: 0.320788 ( -0.009437 0.009582 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.6339e-05 ( -4.28598e-07 4.24278e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-164.504000 542.477500
660.432000 698.404000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.28240 ( -0.433819 1.81353 )
beta : -1.81991 ( -8.18009 7.838058E-02) )
Epeak [keV] : 62.4596 ( -29.9965 203.375 )
Norm@50keV : 4.358968E-03 ( -1.794809E-03 3.380799E-02) )
------------------------------------------------------------
Chi-Squared = 49.27072 using 59 PHA bins.
Reduced chi-squared = 0.8958313 for 55 degrees of freedom
Null hypothesis probability = 0.692
Photon flux (15-150 keV) in 745.0 sec: 0.316678 ( -0.010783 0.010622 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.62482e-05 ( -4.17722e-07 4.16529e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 343.892 sec. to 344.892 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.63232 ( -0.242950 0.251531 )
Norm@50keV : 7.008995E-03 ( -1.127989E-03 1.108152E-03) )
------------------------------------------------------------
Chi-Squared = 53.83978 using 59 PHA bins.
Reduced chi-squared = 0.9445574 for 57 degrees of freedom
Null hypothesis probability = 0.594
Photon flux (15-150 keV) in 1.000 sec: 0.909924 ( -0.13205 0.132096 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.53298e-08 ( -1.1116e-08 1.13416e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 343.892 sec. to 344.892 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.306522 ( -1.68454 1.25563 )
Epeak [keV] : 56.2616 ( -12.5884 168.178 )
Norm@50keV : 3.810602E-02 ( -3.810602E-02 0.283733 )
------------------------------------------------------------
Chi-Squared = 50.61438 using 59 PHA bins.
Reduced chi-squared = 0.9038283 for 56 degrees of freedom
Null hypothesis probability = 0.678
Photon flux (15-150 keV) in 1.000 sec: 0.868299 ( -0.137617 0.137941 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.77263e-08 ( -1.16153e-08 1.31445e-08 ) ergs/cm2
Band function
Time interval is from 343.892 sec. to 344.892 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.268937 ( -1.08313 4.24626 )
beta : -2.62321 ( -7.37679 0.993265 )
Epeak [keV] : 55.1267 ( -28.6420 90.2403 )
Norm@50keV : 4.080443E-02 ( -2.482771E-02 92.8528 )
------------------------------------------------------------
Chi-Squared = 50.24014 using 59 PHA bins.
Reduced chi-squared = 0.9134570 for 55 degrees of freedom
Null hypothesis probability = 0.657
Photon flux (15-150 keV) in 1.000 sec: 0.872976 ( -0.13602 0.136504 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.91173e-08 ( -9.9291e-09 1.26716e-08 ) ergs/cm2
Plot creation:
Fri Jul 25 19:17:34 EDT 2008