batgrbproduct Analysis for Trigger=156838
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): Wed Jan 9 13:30:46 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger156838/GCN5_download_cron
======================================================================
Trigger: 00156838 Segment: 000
BAT Trigger Time: 149331873.216 [s; MET]
Trigger Stop: 149331873.664 [s; MET]
UTC: 2005-09-25T09:04:33.468160 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 64 ms to TRIGTIME + 320 ms
BAT
RA: 303.445191270095 Dec: 34.3345869373457 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.32
Image Trigger?: NO
Rate S/N Ratio: 32.3419232575925 [ if not an image trigger ]
Image S/N Ratio: 12.32
Flight Position: [ source = BAT ]
RA: 303.445191270095 Dec: 34.3345869373457 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 303.487558844444 Dec: 34.3294698362465 [deg; J2000]
{ 20h 13m 57.0s , +34d 19' 46.1" }
+/- 1.50408170747738 [arcmin] (estimated 90% radius based on SNR)
+/- 0.753548371190725 [arcmin] (formal 1-sigma fit error)
SNR: 16.9774899007112
RA = 20h 13m 57.0s (303.487559 deg.)
Dec = 34d 19' 46" (34.329470 deg.)
Angular difference between Flight and Ground position is 2.121520 arcmin
Partial Coding Fraction: 0.4140625 [ including projection effects ]
Duration
T90: 0.0920000076293945 +/- 0.0144222095322683
Measured from: 0.128000020980835
to: 0.220000028610229 [s; relative to TRIGTIME]
T50: 0.0439999997615814 +/- 0.0113137103534657
Measured from: 0.156000018119812
to: 0.200000017881393 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.321999996900558
to: 0.678000003099442 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0.124000012874603
to: 0.22800001502037 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.032563 0.051479 0.046397 0.006313
0.003987 0.004985 0.004711 0.002893 [error]
Peak 0.033339 0.052468 0.046896 0.006243
0.004068 0.005052 0.004760 0.002921 [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 1.28e-08 2.03e-08 2.39e-08 5.45e-08 7.31e-08 1.18e-07 erg/cm2
Error 2.14e-09 2.34e-09 3.49e-09 1.55e-08 8.84e-09 0.00e+00 erg/cm2
Peak flux Power-law 4.01e+00 3.43e+00 2.01e+00 1.76e+00 1.02e+01 1.12e+01 ph/cm2/s
Error 6.66e-01 3.98e-01 2.84e-01 4.53e-01 1.18e+00 1.26e+00 ph/cm2/s
Fluence Cutoff-PL 8.74e-09 2.54e-08 3.21e-08 1.27e-08 7.60e-08 8.04e-08 erg/cm2
Error 2.62e-09 3.25e-09 5.32e-09 7.35e-09 9.06e-09 0.00e+00 erg/cm2
Peak flux Cutoff-PL 2.62e+00 4.17e+00 2.74e+00 5.91e-01 1.00e+01 1.01e+01 ph/cm2/s
Error 8.11e-01 5.27e-01 4.48e-01 2.94e-01 1.19e+00 1.22e+00 ph/cm2/s
Fluence Band 8.61e-09 2.54e-08 3.19e-08 1.29e-08 7.60e-08 7.84e-08 erg/cm2
Error 1.21e-09 2.36e-09 4.19e-09 9.23e-09 8.94e-09 0.00e+00 erg/cm2
Peak flux Band 2.60e+00 4.18e+00 2.75e+00 5.93e-01 1.00e+01 1.01e+01 ph/cm2/s
Error 3.98e-01 4.81e-01 3.21e-01 3.08e-01 1.19e+00 1.11e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.762 0.163 - - 7.62e-02 9.02e-03 87.229 57
CPL -0.370 0.984 61.2 7.9 7.95e-01 1.04e+00 68.046 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.773 0.163 - - 7.49e-02 8.83e-03 87.630 57
CPL -0.306 0.963 61.0 8.0 7.40e-01 9.42e-01 68.874 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: 0.064000 sec.
T50 in the 50-300 keV band: 0.064000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.104 0.124 0.228
T90 0.092 0.128 0.220
T50 0.044 0.156 0.200
Peak 1.000 -0.322 0.678
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
303.4876 +34.3295 0.0114 45.0 -15.7 0.1472 17.0 TRIG_00156838
------------------------------------------
Foreground time interval of the image:
0.060 0.164 (delta_t = 0.104 [sec])
Background time interval of the image:
-299.280 0.060 (delta_t = 299.340 [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 0.060 sec. to 0.164 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.76174 ( -0.159475 0.167347 )
Norm@50keV : 7.624988E-02 ( -9.053990E-03 8.995801E-03) )
------------------------------------------------------------
Chi-Squared = 87.22941 using 59 PHA bins.
Reduced chi-squared = 1.530341 for 57 degrees of freedom
Null hypothesis probability = 6.126E-03
Photon flux (15-150 keV) in 0.1040 sec: 10.3548 ( -1.20593 1.208 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.31292e-08 ( -8.83428e-09 8.85373e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.060 sec. to 0.164 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.370134 ( -1.07000 0.897158 )
Epeak [keV] : 61.2224 ( -6.79946 9.03802 )
Norm@50keV : 0.794504 ( -0.486585 1.59677 )
------------------------------------------------------------
Chi-Squared = 68.04582 using 59 PHA bins.
Reduced chi-squared = 1.215104 for 56 degrees of freedom
Null hypothesis probability = 0.130
Photon flux (15-150 keV) in 0.1040 sec: 10.1612 ( -1.20831 1.2141 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.60162e-08 ( -9.03146e-09 9.07951e-09 ) ergs/cm2
Band function
Time interval is from 0.060 sec. to 0.164 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.324527 ( -0.853480 1.04566 )
beta : -9.30586 ( -0.694139 19.3058 )
Epeak [keV] : 61.6960 ( -7.25444 8.57651 )
Norm@50keV : 0.749991 ( -0.148113 8.725876E-02) )
------------------------------------------------------------
Chi-Squared = 68.06091 using 59 PHA bins.
Reduced chi-squared = 1.237471 for 55 degrees of freedom
Null hypothesis probability = 0.111
Photon flux (15-150 keV) in 0.1040 sec: 10.1241 ( -1.16984 1.1109 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.60131e-08 ( -9.00484e-09 8.87744e-09 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.060 sec. to 0.168 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.77257 ( -0.158659 0.166852 )
Norm@50keV : 7.487438E-02 ( -8.861043E-03 8.797802E-03) )
------------------------------------------------------------
Chi-Squared = 87.63043 using 59 PHA bins.
Reduced chi-squared = 1.537376 for 57 degrees of freedom
Null hypothesis probability = 5.652E-03
Photon flux (15-150 keV) in 0.1080 sec: 10.2092 ( -1.1831 1.1862 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.060 sec. to 0.168 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.305855 ( -1.04434 0.881136 )
Epeak [keV] : 61.0061 ( -6.84894 9.08716 )
Norm@50keV : 0.739831 ( -0.449271 1.43445 )
------------------------------------------------------------
Chi-Squared = 68.87407 using 59 PHA bins.
Reduced chi-squared = 1.229894 for 56 degrees of freedom
Null hypothesis probability = 0.116
Photon flux (15-150 keV) in 0.1080 sec: 10.0282 ( -1.18724 1.191 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.74753e-08 ( -9.15365e-09 9.19393e-09 ) ergs/cm2
Band function
Time interval is from 0.060 sec. to 0.168 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.272394 ( -0.848203 1.04325 )
beta : -9.35487 ( -0.645125 19.3548 )
Epeak [keV] : 60.9202 ( -6.75692 7.82246 )
Norm@50keV : 0.718492 ( -7.999641E-02 0.596928 )
------------------------------------------------------------
Chi-Squared = 68.87997 using 59 PHA bins.
Reduced chi-squared = 1.252363 for 55 degrees of freedom
Null hypothesis probability = 9.880E-02
Photon flux (15-150 keV) in 0.1080 sec: 10.0268 ( -1.18493 1.1915 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.75642e-08 ( 0 0 ) ergs/cm2
Plot creation:
Wed Jan 9 13:52:27 EST 2008