batgrbproduct Analysis for Trigger=323984
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): Sun Sep 7 13:13:25 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger323984/SDC
======================================================================
Trigger: 00323984 Segment: 000
BAT Trigger Time: 242400799.424 [s; MET]
Trigger Stop: 242400800.448 [s; MET]
UTC: 2008-09-06T13:33:16.347220 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 227.890126999499 Dec: -80.4861395765144 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.72
Image Trigger?: NO
Rate S/N Ratio: 10.6301458127346 [ if not an image trigger ]
Image S/N Ratio: 6.72
Flight Position: [ source = BAT ]
RA: 227.890126999499 Dec: -80.4861395765144 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 228.05211929383 Dec: -80.5419207132193 [deg; J2000]
{ 15h 12m 12.5s , -80d 32' 30.9" }
+/- 1.51197335403637 [arcmin] (estimated 90% radius based on SNR)
+/- 0.612788752845814 [arcmin] (formal 1-sigma fit error)
SNR: 16.8510417633008
Angular difference between Flight and Ground position is 3.710444 arcmin
Partial Coding Fraction: 0.59375 [ including projection effects ]
Duration
T90: 142.472000002861 +/- 18.7492722151846
Measured from: -69.8079999983311
to: 72.66400000453 [s; relative to TRIGTIME]
T50: 40.272000014782 +/- 5.84014520920662
Measured from: 2.25999999046326
to: 42.5320000052452 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0639999806880951
to: 0.936000019311905 [s; relative to TRIGTIME]
Total Fluence
Measured from: -106.451999992132
to: 109.536000013351 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.705168 2.233225 1.592764 0.221862
0.087010 0.085918 0.076417 0.068339 [error]
Peak 0.038893 0.044573 0.038093 0.007539
0.006821 0.006761 0.006251 0.005242 [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 5.35e-07 9.26e-07 1.22e-06 3.29e-06 3.57e-06 5.98e-06 erg/cm2
Error 4.42e-08 4.48e-08 7.70e-08 4.55e-07 1.82e-07 5.10e-07 erg/cm2
Peak flux Power-law 3.38e-01 3.36e-01 2.34e-01 2.59e-01 1.01e+00 1.17e+00 ph/cm2/s
Error 8.90e-02 5.62e-02 4.94e-02 1.10e-01 1.63e-01 1.91e-01 ph/cm2/s
Fluence Cutoff-PL 5.16e-07 9.43e-07 1.24e-06 2.41e-06 3.51e-06 5.09e-06 erg/cm2
Error 4.03e-08 5.20e-08 8.11e-08 1.25e-06 2.05e-07 1.09e-06 erg/cm2
Peak flux Cutoff-PL 3.01e-01 3.60e-01 2.46e-01 1.20e-01 9.83e-01 1.03e+00 ph/cm2/s
Error 1.05e-01 6.99e-02 5.61e-02 1.73e-01 1.69e-01 2.18e-01 ph/cm2/s
Fluence Band 5.05e-07 9.49e-07 1.21e-06 3.00e-06 3.52e-06 5.66e-06 erg/cm2
Error 7.39e-08 6.02e-08 9.09e-08 5.07e-07 2.07e-07 1.04e-06 erg/cm2
Peak flux Band 3.01e-01 3.60e-01 2.46e-01 1.20e-01 9.83e-01 1.03e+00 ph/cm2/s
Error 1.05e-01 6.99e-02 5.61e-02 1.73e-01 1.69e-01 2.40e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.599 0.086 - - 1.77e-03 8.35e-05 51.659 57
CPL 1.329 0.313 124.8 4958.0 2.40e-03 0.00e+00 50.686 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.519 0.275 - - 8.05e-03 1.35e-03 47.085 57
CPL 0.808 1.329 81.2 4975.0 1.88e-02 4.98e-02 45.877 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: 86.080000 sec.
T50 in the 50-300 keV band: 33.600000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 215.988 -106.452 109.536
T90 142.472 -69.808 72.664
T50 40.272 2.260 42.532
Peak 1.000 -0.064 0.936
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
228.0521 -80.5419 0.0114 26.3 -110.0 2.9430 16.9 TRIG_00323984
------------------------------------------
Foreground time interval of the image:
-106.452 16.581 (delta_t = 123.033 [sec])
Background time interval of the image:
-239.424 -106.452 (delta_t = 132.972 [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 -106.452 sec. to 109.536 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.59855 ( -8.609998E-02 8.664370E-02) )
Norm@50keV : 1.768612E-03 ( -8.372474E-05 8.329109E-05) )
------------------------------------------------------------
Chi-Squared = 51.65937 using 59 PHA bins.
Reduced chi-squared = 0.9063047 for 57 degrees of freedom
Null hypothesis probability = 0.675
Photon flux (15-150 keV) in 216.0 sec: 0.227173 ( -0.010857 0.01088 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.57348e-06 ( -1.81699e-07 1.8239e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -106.452 sec. to 109.536 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.32896 ( -0.287893 0.337499 )
Epeak [keV] : 124.838 ( -40.7793 9875.16 )
Norm@50keV : 2.399390E-03 ( )
------------------------------------------------------------
Chi-Squared = 50.68568 using 59 PHA bins.
Reduced chi-squared = 0.9051014 for 56 degrees of freedom
Null hypothesis probability = 0.676
Photon flux (15-150 keV) in 216.0 sec: 0.224279 ( -0.011729 0.011373 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.51238e-06 ( -2.06993e-07 2.02068e-07 ) ergs/cm2
Band function
Time interval is from -106.452 sec. to 109.536 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.08432 ( -8.91568 3.90221 )
beta : -1.67591 ( -8.32409 0.143567 )
Epeak [keV] : 66.0860 ( -65.9860 9933.91 )
Norm@50keV : 3.581990E-03 ( -1.882134E-02 89.7970 )
------------------------------------------------------------
Chi-Squared = 50.50230 using 59 PHA bins.
Reduced chi-squared = 0.9182237 for 55 degrees of freedom
Null hypothesis probability = 0.647
Photon flux (15-150 keV) in 216.0 sec: 0.223771 ( -0.011866 0.012197 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.51981e-06 ( -2.0898e-07 2.06021e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.064 sec. to 0.936 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.51912 ( -0.271756 0.278527 )
Norm@50keV : 8.052405E-03 ( -1.356993E-03 1.338255E-03) )
------------------------------------------------------------
Chi-Squared = 47.08509 using 59 PHA bins.
Reduced chi-squared = 0.8260542 for 57 degrees of freedom
Null hypothesis probability = 0.823
Photon flux (15-150 keV) in 1.000 sec: 1.01052 ( -0.163055 0.16326 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.61409e-08 ( -1.38582e-08 1.41513e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.064 sec. to 0.936 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.808485 ( -1.41585 1.24218 )
Epeak [keV] : 81.2494 ( -31.2457 9918.75 )
Norm@50keV : 1.882520E-02 ( -1.882520E-02 8.075210E-02) )
------------------------------------------------------------
Chi-Squared = 45.87685 using 59 PHA bins.
but latest trial 19.9893 gives Chi-Squared = 2.81647
Reduced chi-squared = 0.8192295 for 56 degrees of freedom
Null hypothesis probability = 0.831
Photon flux (15-150 keV) in 1.000 sec: 0.982705 ( -0.169354 0.168685 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.20785e-08 ( -1.51426e-08 1.55034e-08 ) ergs/cm2
Band function
Time interval is from -0.064 sec. to 0.936 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.811210 ( -9.18879 1.41477 )
beta : -9.36431 ( -0.635694 19.3642 )
Epeak [keV] : 81.4246 ( -29.3792 9918.58 )
Norm@50keV : 1.875530E-02 ( -1.875530E-02 8.116899E-02) )
------------------------------------------------------------
Chi-Squared = 45.87688 using 59 PHA bins.
Reduced chi-squared = 0.8341250 for 55 degrees of freedom
Null hypothesis probability = 0.805
Photon flux (15-150 keV) in 1.000 sec: 0.982686 ( -0.169341 0.168924 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.1976e-08 ( -1.50668e-08 1.55412e-08 ) ergs/cm2
Plot creation:
Sun Sep 7 13:59:54 EDT 2008