batgrbproduct Analysis for Trigger=321551
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): Sat Aug 23 23:07:45 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger321551/GCN5_download_cron
======================================================================
Trigger: 00321551 Segment: 000
BAT Trigger Time: 241183658.148 [s; MET]
Trigger Stop: 241183658.164 [s; MET]
UTC: 2008-08-23T11:27:35.107080 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 75.264742049925 Dec: 45.2810981393975 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 21.36
Image Trigger?: NO
Rate S/N Ratio: 255.998046867549 [ if not an image trigger ]
Image S/N Ratio: 21.36
Flight Position: [ source = BAT ]
RA: 75.264742049925 Dec: 45.2810981393975 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 75.2749583079764 Dec: 45.2729800828829 [deg; J2000]
{ 05h 01m 06.0s , +45d 16' 22.7" }
+/- 0.391249276011093 [arcmin] (estimated 90% radius based on SNR)
+/- 0.100397114110427 [arcmin] (formal 1-sigma fit error)
SNR: 116.232505273885
Angular difference between Flight and Ground position is 0.650617 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 0.260000020265579 +/- 0.00799998641014099
Measured from: -0.0919999182224274
to: 0.168000102043152 [s; relative to TRIGTIME]
T50: 0.159999996423721 +/- 0.004
Measured from: -0.0559999048709869
to: 0.104000091552734 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.314000010490417
to: 0.685999989509583 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.164000004529953
to: 0.532000005245209 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 3.230281 3.120982 0.766242 0.018846
0.022929 0.022399 0.011790 0.003815 [error]
Peak 3.230541 3.121155 0.766185 0.018702
0.022932 0.022403 0.011793 0.003818 [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 1.50e-06 1.08e-06 5.15e-07 3.45e-07 3.27e-06 3.43e-06 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Power-law 7.17e+01 2.90e+01 6.91e+00 1.99e+00 1.09e+02 1.10e+02 ph/cm2/s
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Fluence Cutoff-PL 8.04e-07 1.29e-06 5.77e-07 5.67e-08 2.85e-06 2.53e-06 erg/cm2
Error 2.65e-08 1.55e-08 7.66e-09 6.70e-08 0.00e+00 0.00e+00 erg/cm2
Peak flux Cutoff-PL 4.30e+01 3.36e+01 8.04e+00 4.30e-01 8.51e+01 8.51e+01 ph/cm2/s
Error 2.43e+00 7.01e-01 2.05e-01 5.48e-02 2.76e+00 2.76e+00 ph/cm2/s
Fluence Band 9.39e-07 1.28e-06 5.77e-07 5.97e-08 2.86e-06 2.84e-06 erg/cm2
Error 2.42e-08 1.51e-08 2.36e-08 5.56e-08 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 4.42e+01 3.35e+01 8.03e+00 4.59e-01 8.61e+01 8.61e+01 ph/cm2/s
Error 2.44e+00 6.39e-01 1.93e-01 1.83e-01 1.80e+00 3.22e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.072 0.000 - - 3.78e-01 0.00e+00 755.858 57
CPL 0.504 0.206 27.8 1.7 7.74e+00 1.89e+00 42.320 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.072 0.000 - - 3.76e-01 0.00e+00 756.523 57
CPL 0.501 0.207 27.8 1.7 7.73e+00 1.89e+00 42.011 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: 0.256000 sec.
T50 in the 50-300 keV band: 0.192000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.696 -0.164 0.532
T90 0.260 -0.092 0.168
T50 0.160 -0.056 0.104
Peak 1.000 -0.314 0.686
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
75.2750 +45.2730 0.0017 0.0 -105.5 7.1460 116.2 TRIG_00321551
------------------------------------------
Foreground time interval of the image:
-0.164 0.532 (delta_t = 0.696 [sec])
Background time interval of the image:
-119.148 -0.164 (delta_t = 118.984 [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 -0.164 sec. to 0.532 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.07188 ( )
Norm@50keV : 0.377774 ( )
------------------------------------------------------------
Chi-Squared = 755.8582 using 59 PHA bins.
Reduced chi-squared = 13.26067 for 57 degrees of freedom
Null hypothesis probability = 0.00
Photon flux (15-150 keV) in 0.6960 sec: 109.512 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.26814e-06 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.164 sec. to 0.532 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.504289 ( -0.210748 0.202199 )
Epeak [keV] : 27.8236 ( -1.74963 1.56566 )
Norm@50keV : 7.73919 ( -1.62177 2.15609 )
------------------------------------------------------------
Chi-Squared = 42.32048 using 59 PHA bins.
Reduced chi-squared = 0.7557229 for 56 degrees of freedom
Null hypothesis probability = 0.912
Photon flux (15-150 keV) in 0.6960 sec: 85.5628 ( -2.7532 2.7923 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.84913e-06 ( -6.6633e-08 6.72802e-08 ) ergs/cm2
Band function
Time interval is from -0.164 sec. to 0.532 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.26140 ( -0.107452 0.405686 )
beta : -9.37163 ( -4.90123 15.0985 )
Epeak [keV] : 19.8641 ( -2.51418 1.19064 )
Norm@50keV : 3.15202 ( -2.62417 5.89978 )
------------------------------------------------------------
Chi-Squared = 86.48078 using 59 PHA bins.
Reduced chi-squared = 1.572378 for 55 degrees of freedom
Null hypothesis probability = 4.297E-03
Photon flux (15-150 keV) in 0.6960 sec: 86.3814 ( -2.2518 2.2198 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85624e-06 ( -5.22202e-08 5.88809e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.164 sec. to 0.536 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.07211 ( )
Norm@50keV : 0.375581 ( )
------------------------------------------------------------
Chi-Squared = 756.5225 using 59 PHA bins.
Reduced chi-squared = 13.27232 for 57 degrees of freedom
Null hypothesis probability = 0.00
Photon flux (15-150 keV) in 0.7000 sec: 108.901 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.26822e-06 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.164 sec. to 0.536 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.500872 ( -0.210538 0.202733 )
Epeak [keV] : 27.8428 ( -1.74959 1.56034 )
Norm@50keV : 7.72942 ( -1.62356 2.15133 )
------------------------------------------------------------
Chi-Squared = 42.01093 using 59 PHA bins.
Reduced chi-squared = 0.7501952 for 56 degrees of freedom
Null hypothesis probability = 0.917
Photon flux (15-150 keV) in 0.7000 sec: 85.0599 ( -2.7371 2.7771 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.84872e-06 ( -6.66176e-08 6.73078e-08 ) ergs/cm2
Band function
Time interval is from -0.164 sec. to 0.536 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.26181 ( -0.269982 0.186014 )
beta : -9.09107 ( -5.09061 14.9092 )
Epeak [keV] : 19.8606 ( -1.98465 1.60611 )
Norm@50keV : 3.13997 ( -3.18529 5.11199 )
------------------------------------------------------------
Chi-Squared = 86.54496 using 59 PHA bins.
Reduced chi-squared = 1.573545 for 55 degrees of freedom
Null hypothesis probability = 4.240E-03
Photon flux (15-150 keV) in 0.7000 sec: 86.1345 ( -1.5479 2.0621 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85878e-06 ( -5.48814e-08 5.4586e-08 ) ergs/cm2
Plot creation:
Sat Aug 23 23:16:25 EDT 2008