batgrbproduct Analysis for Trigger=283320
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 Dec 14 03:11:24 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger283320/SDC
======================================================================
Trigger: 00283320 Segment: 000
BAT Trigger Time: 204734464.896 [s; MET]
Trigger Stop: 204734465.92 [s; MET]
UTC: 2007-06-28T14:41:02.843960 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 115.283792218838 Dec: -20.2846481551998 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.08
Image Trigger?: NO
Rate S/N Ratio: 24.3721152139079 [ if not an image trigger ]
Image S/N Ratio: 12.08
Flight Position: [ source = BAT ]
RA: 115.283792218838 Dec: -20.2846481551998 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 115.270908487762 Dec: -20.2812034701194 [deg; J2000]
{ 07h 41m 05.0s , -20d 16' 52.3" }
+/- 1.23542808917424 [arcmin] (estimated 90% radius based on SNR)
+/- 0.298287742507199 [arcmin] (formal 1-sigma fit error)
SNR: 22.4879860761198
RA = 7h 41m 5.0s (115.270908 deg.)
Dec = -20d 16' 52" (-20.281203 deg.)
Angular difference between Flight and Ground position is 0.753972 arcmin
Partial Coding Fraction: 0.5859375 [ including projection effects ]
Duration
T90: 39.1159999966621 +/- 4.03407337007759
Measured from: -26.1839999854565
to: 12.9320000112057 [s; relative to TRIGTIME]
T50: 6.18000000715256 +/- 0.560285638168507
Measured from: 1.63600000739098
to: 7.81600001454353 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 4.89599999785423
to: 5.89599999785423 [s; relative to TRIGTIME]
Total Fluence
Measured from: -31.7360000014305
to: 16.1879999935627 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.079741 2.164074 1.451160 0.026390
0.060155 0.068333 0.065241 0.074139 [error]
Peak 0.171961 0.214327 0.145225 0.016600
0.010671 0.012291 0.011247 0.011756 [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 7.17e-07 1.03e-06 1.10e-06 2.17e-06 3.51e-06 5.00e-06 erg/cm2
Error 5.29e-08 4.27e-08 6.90e-08 2.99e-07 1.54e-07 3.48e-07 erg/cm2
Peak flux Power-law 1.96e+00 1.70e+00 1.01e+00 9.02e-01 5.05e+00 5.57e+00 ph/cm2/s
Error 2.16e-01 1.16e-01 9.79e-02 1.76e-01 3.43e-01 3.72e-01 ph/cm2/s
Fluence Cutoff-PL 7.03e-07 1.04e-06 1.10e-06 1.85e-06 3.48e-06 4.60e-06 erg/cm2
Error 6.46e-08 4.76e-08 6.99e-08 5.59e-07 1.79e-07 6.74e-07 erg/cm2
Peak flux Cutoff-PL 1.87e+00 1.75e+00 1.03e+00 6.30e-01 4.99e+00 5.28e+00 ph/cm2/s
Error 2.51e-01 1.43e-01 1.05e-01 2.90e-01 3.57e-01 5.22e-01 ph/cm2/s
Fluence Band 6.98e-07 1.03e-06 1.10e-06 1.85e-06 3.48e-06 4.53e-06 erg/cm2
Error 6.38e-08 4.87e-08 7.08e-08 6.42e-07 1.79e-07 6.91e-07 erg/cm2
Peak flux Band 1.87e+00 1.75e+00 1.03e+00 6.31e-01 4.99e+00 5.28e+00 ph/cm2/s
Error 2.52e-01 1.43e-01 1.05e-01 4.22e-01 3.59e-01 4.60e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.908 0.085 - - 7.98e-03 3.53e-04 52.674 57
CPL 1.806 0.300 93.1 5000.0 8.98e-03 3.13e-03 52.365 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.750 0.124 - - 3.74e-02 2.75e-03 52.977 57
CPL 1.466 0.431 88.6 4974.5 5.29e-02 3.15e-02 51.887 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: 11.712000 sec.
T50 in the 50-300 keV band: 4.544000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 47.924 -31.736 16.188
T90 39.116 -26.184 12.932
T50 6.180 1.636 7.816
Peak 1.000 4.896 5.896
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
115.2709 -20.2812 0.0086 38.2 -20.3 6.0801 22.5 TRIG_00283320
------------------------------------------
Foreground time interval of the image:
-31.736 16.188 (delta_t = 47.924 [sec])
Background time interval of the image:
-117.291 -31.736 (delta_t = 85.555 [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 -31.736 sec. to 16.188 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.90807 ( -8.472621E-02 8.591902E-02) )
Norm@50keV : 7.977285E-03 ( -3.547622E-04 3.519114E-04) )
------------------------------------------------------------
Chi-Squared = 52.67379 using 59 PHA bins.
Reduced chi-squared = 0.9241015 for 57 degrees of freedom
Null hypothesis probability = 0.638
Photon flux (15-150 keV) in 47.92 sec: 1.14876 ( -0.05031 0.05056 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.5147e-06 ( -1.53425e-07 1.5482e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -31.736 sec. to 16.188 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.80634 ( -0.326330 0.274117 )
Epeak [keV] : 93.0792 ( -93.0692 9906.92 )
Norm@50keV : 8.979271E-03 ( -2.277546E-03 3.985583E-03) )
------------------------------------------------------------
Chi-Squared = 52.36491 using 59 PHA bins.
but latest trial 6.701556E-03 gives Chi-Squared = 3.92647
Reduced chi-squared = 0.9350877 for 56 degrees of freedom
Null hypothesis probability = 0.613
Photon flux (15-150 keV) in 47.92 sec: 1.13932 ( -0.05707 0.05656 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.48395e-06 ( -1.80218e-07 1.77208e-07 ) ergs/cm2
Band function
Time interval is from -31.736 sec. to 16.188 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.80751 ( -6.37930 0.327433 )
beta : -9.32867 ( -0.671334 7.50037 )
Epeak [keV] : 93.9250 ( -43.7866 9906.08 )
Norm@50keV : 8.961161E-03 ( -1.316690E-03 4.001499E-03) )
------------------------------------------------------------
Chi-Squared = 52.36475 using 59 PHA bins.
Reduced chi-squared = 0.9520864 for 55 degrees of freedom
Null hypothesis probability = 0.576
Photon flux (15-150 keV) in 47.92 sec: 1.13938 ( -0.05719 0.05653 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.4796e-06 ( -1.81919e-07 1.76475e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 4.896 sec. to 5.896 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.75018 ( -0.123228 0.125770 )
Norm@50keV : 3.736606E-02 ( -2.760854E-03 2.730794E-03) )
------------------------------------------------------------
Chi-Squared = 52.97734 using 59 PHA bins.
Reduced chi-squared = 0.9294271 for 57 degrees of freedom
Null hypothesis probability = 0.627
Photon flux (15-150 keV) in 1.000 sec: 5.05286 ( -0.343 0.34338 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.44782e-07 ( -2.6297e-08 2.6611e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.896 sec. to 5.896 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.46605 ( -0.516215 0.344825 )
Epeak [keV] : 88.5952 ( -37.5094 9911.41 )
Norm@50keV : 5.288014E-02 ( -1.760430E-02 4.544739E-02) )
------------------------------------------------------------
Chi-Squared = 51.88672 using 59 PHA bins.
but latest trial 32.3150 gives Chi-Squared = 5.25273
Reduced chi-squared = 0.9265485 for 56 degrees of freedom
Null hypothesis probability = 0.631
Photon flux (15-150 keV) in 1.000 sec: 4.98733 ( -0.35602 0.35767 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.36794e-07 ( -2.9767e-08 2.9504e-08 ) ergs/cm2
Band function
Time interval is from 4.896 sec. to 5.896 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.46485 ( -0.381636 0.515036 )
beta : -9.24420 ( -0.755798 7.58957 )
Epeak [keV] : 88.2825 ( -31.6152 9911.72 )
Norm@50keV : 5.296770E-02 ( -1.770032E-02 4.535821E-02) )
------------------------------------------------------------
Chi-Squared = 51.88651 using 59 PHA bins.
Reduced chi-squared = 0.9433910 for 55 degrees of freedom
Null hypothesis probability = 0.594
Photon flux (15-150 keV) in 1.000 sec: 4.98753 ( -0.35878 0.35848 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.36366e-07 ( -2.9684e-08 2.9616e-08 ) ergs/cm2
Plot creation:
Fri Dec 14 03:29:15 EST 2007