batgrbproduct Analysis for Trigger=202746
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 Dec 31 16:08:34 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger202746/GCN5_download_cron
======================================================================
Trigger: 00202746 Segment: 000
BAT Trigger Time: 165010601.272 [s; MET]
Trigger Stop: 165010601.608 [s; MET]
UTC: 2006-03-25T20:16:40.179120 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 8 ms to TRIGTIME + 320 ms
BAT
RA: 286.828340324767 Dec: 9.2697657951551 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 5.43
Image Trigger?: NO
Rate S/N Ratio: 18.4390889145858 [ if not an image trigger ]
Image S/N Ratio: 5.43
Flight Position: [ source = BAT ]
RA: 286.828340324767 Dec: 9.2697657951551 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 286.815801212747 Dec: 9.31530011942075 [deg; J2000]
{ 19h 07m 15.8s , +09d 18' 55.1" }
+/- 2.26201165542159 [arcmin] (estimated 90% radius based on SNR)
+/- 1.63589777906946 [arcmin] (formal 1-sigma fit error)
SNR: 9.47757396214559
RA = 19h 7m 15.8s (286.815801 deg.)
Dec = 9d 18' 55" (9.315300 deg.)
Angular difference between Flight and Ground position is 2.831151 arcmin
Partial Coding Fraction: 0.328125 [ including projection effects ]
Duration
T90: 0.0240000188350677 +/- 0.00894426338008669
Measured from: 0.315999984741211
to: 0.340000003576279 [s; relative to TRIGTIME]
T50: 0.0119999945163727 +/- 0.00565686571343518
Measured from: 0.319999992847443
to: 0.331999987363815 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.168000012636185
to: 0.831999987363815 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0.315999984741211
to: 0.343999981880188 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.024523 0.022581 0.004449 0.001838
0.003985 0.003506 0.002558 0.001283 [error]
Peak 0.024633 0.024679 0.005076 0.001368
0.004068 0.003727 0.002631 0.001366 [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 9.59e-09 5.31e-09 1.85e-09 8.39e-10 1.72e-08 1.76e-08 erg/cm2
Error 2.32e-09 1.31e-09 7.66e-10 5.84e-10 3.83e-09 3.96e-09 erg/cm2
Peak flux Power-law 1.04e+01 3.26e+00 5.68e-01 1.15e-01 1.43e+01 1.43e+01 ph/cm2/s
Error 2.55e+00 7.85e-01 2.27e-01 7.47e-02 3.21e+00 3.22e+00 ph/cm2/s
Fluence Cutoff-PL 8.89e-09 9.09e-09 1.49e-09 1.51e-11 1.95e-08 1.95e-08 erg/cm2
Error 2.75e-09 2.65e-09 1.28e-09 8.05e-11 4.03e-09 4.03e-09 erg/cm2
Peak flux Cutoff-PL 8.87e+00 5.98e+00 5.59e-01 2.59e-03 1.54e+01 1.43e+01 ph/cm2/s
Error 3.02e+00 1.70e+00 3.22e-01 1.14e-02 3.40e+00 3.21e+00 ph/cm2/s
Fluence Band 9.04e-09 8.96e-09 1.53e-09 5.93e-11 1.95e-08 1.89e-08 erg/cm2
Error 2.57e-09 8.14e-10 2.45e-10 4.02e-09 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 9.54e+00 5.75e+00 6.00e-01 1.28e-02 1.56e+01 1.55e+01 ph/cm2/s
Error 2.90e+00 1.35e+00 2.87e-01 3.30e-02 3.35e+00 3.83e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.523 0.372 - - 3.85e-02 1.29e-02 55.964 57
CPL -0.312 2.439 21.9 13.0 1.08e+01 0.00e+00 47.045 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.521 0.369 - - 3.47e-02 1.15e-02 58.852 57
CPL -0.617 2.259 23.7 11.2 1.43e+01 1.21e+02 48.637 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.028 0.316 0.344
T90 0.024 0.316 0.340
T50 0.012 0.320 0.332
Peak 1.000 -0.168 0.832
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
286.8158 +9.3153 0.0201 47.5 -167.9 0.0588 9.5 TRIG_00202746
------------------------------------------
Foreground time interval of the image:
0.308 0.336 (delta_t = 0.028 [sec])
Background time interval of the image:
-10.280 0.308 (delta_t = 10.588 [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 0.308 sec. to 0.336 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.52282 ( -0.330204 0.414507 )
Norm@50keV : 3.848853E-02 ( -1.308301E-02 1.269085E-02) )
------------------------------------------------------------
Chi-Squared = 55.96405 using 59 PHA bins.
Reduced chi-squared = 0.9818255 for 57 degrees of freedom
Null hypothesis probability = 0.514
Photon flux (15-150 keV) in 2.8000E-02 sec: 15.8586 ( -3.551 3.5514 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71968e-08 ( -3.8278e-09 3.82886e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.308 sec. to 0.336 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.311942 ( -2.68806 2.19007 )
Epeak [keV] : 21.9342 ( -18.3789 7.71498 )
Norm@50keV : 10.8216 ( )
------------------------------------------------------------
Chi-Squared = 47.04506 using 59 PHA bins.
but latest trial 3.55532 gives Chi-Squared = 51.9862
Reduced chi-squared = 0.8400903 for 56 degrees of freedom
Null hypothesis probability = 0.797
Photon flux (15-150 keV) in 2.8000E-02 sec: 16.9949 ( -3.7214 3.6969 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.94983e-08 ( -4.02674e-09 4.03365e-09 ) ergs/cm2
Band function
Time interval is from 0.308 sec. to 0.336 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -7.73816 ( -0.375300 0.634031 )
beta : -3.52351 ( -4.00238 1.96196 )
Epeak [keV] : 9.21360 ( -5.78403 5.33586 )
Norm@50keV : 5.22846 ( -11.4758 1012.50 )
------------------------------------------------------------
Chi-Squared = 55.96405 using 59 PHA bins.
Reduced chi-squared = 1.017528 for 55 degrees of freedom
Null hypothesis probability = 0.438
Photon flux (15-150 keV) in 2.8000E-02 sec: 16.8659 ( -3.5854 3.5622 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.95296e-08 ( -4.02987e-09 4.00456e-09 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.308 sec. to 0.340 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.52054 ( -0.326227 0.410995 )
Norm@50keV : 3.467716E-02 ( -1.173578E-02 1.133636E-02) )
------------------------------------------------------------
Chi-Squared = 58.85160 using 59 PHA bins.
Reduced chi-squared = 1.032484 for 57 degrees of freedom
Null hypothesis probability = 0.408
Photon flux (15-150 keV) in 3.2000E-02 sec: 14.2615 ( -3.2124 3.2128 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.76824e-08 ( -3.95382e-09 3.95418e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.308 sec. to 0.340 sec.
Parameters : value lower 90% higher 90%
Photon index: -0.616942 ( -2.38303 2.13442 )
Epeak [keV] : 23.6807 ( -14.7170 7.76640 )
Norm@50keV : 14.3174 ( -14.3174 227.708 )
------------------------------------------------------------
Chi-Squared = 48.63673 using 59 PHA bins.
but latest trial -38358.1 gives Chi-Squared = 3.74177
but latest trial 30.9811 gives Chi-Squared = 4.74965
Reduced chi-squared = 0.8685131 for 56 degrees of freedom
Null hypothesis probability = 0.747
Photon flux (15-150 keV) in 3.2000E-02 sec: 15.4104 ( -3.4092 3.3829 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.06898e-08 ( -4.23485e-09 4.23875e-09 ) ergs/cm2
Band function
Time interval is from 0.308 sec. to 0.340 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.52702 ( -0.283766 0.693693 )
beta : -9.11591 ( -0.884090 5.29866 )
Epeak [keV] : 11.1867 ( -3.28733 4.02045 )
Norm@50keV : 0.476458 ( -80.1184 2178.90 )
------------------------------------------------------------
Chi-Squared = 54.00918 using 59 PHA bins.
Reduced chi-squared = 0.9819850 for 55 degrees of freedom
Null hypothesis probability = 0.512
Photon flux (15-150 keV) in 3.2000E-02 sec: 15.6166 ( -3.4811 3.2219 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.07264e-08 ( -4.22413e-09 4.21494e-09 ) ergs/cm2
Plot creation:
Mon Dec 31 16:14:18 EST 2007