batgrbproduct Analysis for Trigger=332931
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 Oct 29 10:16:00 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger332931/GCN5_download_cron
======================================================================
Trigger: 00332931 Segment: 000
BAT Trigger Time: 246937440 [s; MET]
Trigger Stop: 246937504 [s; MET]
UTC: 2008-10-29T01:43:56.788020 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 346.703787157334 Dec: -68.159638914543 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 11.49
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 11.49
Flight Position: [ source = BAT ]
RA: 346.703787157334 Dec: -68.159638914543 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 346.778883990558 Dec: -68.1778518697792 [deg; J2000]
{ 23h 07m 06.9s , -68d 10' 40.3" }
+/- 2.1847179070852 [arcmin] (estimated 90% radius based on SNR)
+/- 1.14957336047567 [arcmin] (formal 1-sigma fit error)
SNR: 9.96019528920441
Angular difference between Flight and Ground position is 2.000445 arcmin
Partial Coding Fraction: 0.5859375 [ including projection effects ]
Duration
T90: 269.952000021935 +/- 45.6827768024956
Measured from: -24.0879999101162
to: 245.864000111818 [s; relative to TRIGTIME]
T50: 101.759999990463 +/- 35.2668456032209
Measured from: 15.2720001041889
to: 117.032000094652 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 52.3720000088215
to: 53.3720000088215 [s; relative to TRIGTIME]
Total Fluence
Measured from: -36.3120000064373
to: 269.159999996424 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.727782 1.229092 0.908302 0.252932
0.111382 0.112004 0.100393 0.088843 [error]
Peak 0.014912 0.020714 0.009016 0.007125
0.006046 0.006459 0.005518 0.005084 [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 2.64e-07 5.05e-07 7.45e-07 2.36e-06 2.10e-06 3.89e-06 erg/cm2
Error 4.90e-08 5.72e-08 9.79e-08 6.71e-07 2.41e-07 7.41e-07 erg/cm2
Peak flux Power-law 1.69e-01 1.55e-01 9.75e-02 9.42e-02 4.61e-01 5.16e-01 ph/cm2/s
Error 1.05e-01 5.88e-02 7.43e-02 1.13e-01 1.70e-01 1.90e-01 ph/cm2/s
Fluence Cutoff-PL 2.44e-07 5.30e-07 7.70e-07 1.20e-06 2.04e-06 2.71e-06 erg/cm2
Error 5.79e-08 7.06e-08 1.09e-07 1.25e-06 2.65e-07 9.20e-07 erg/cm2
Peak flux Cutoff-PL 1.69e-01 1.55e-01 9.75e-02 9.35e-02 4.61e-01 5.15e-01 ph/cm2/s
Error 1.05e-01 5.88e-02 7.43e-02 1.12e-01 1.70e-01 1.90e-01 ph/cm2/s
Fluence Band 2.26e-07 5.57e-07 7.37e-07 1.84e-06 2.04e-06 3.34e-06 erg/cm2
Error 6.54e-08 7.81e-08 1.04e-07 5.77e-07 2.47e-07 1.06e-06 erg/cm2
Peak flux Band 1.59e-01 1.52e-01 2.12e+00 2.04e+00 9.98e+00 5.25e-01 ph/cm2/s
Error 5.74e-02 5.52e+03 8.32e+00 5.45e+03 0.00e+00 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.438 0.180 - - 7.18e-04 7.57e-05 50.678 57
CPL 0.960 0.754 110.0 4968.2 1.25e-03 1.31e-03 49.469 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.665 0.794 - - 3.51e-03 1.45e-03 60.018 57
CPL 1.664 0.798 9992.0 5000.0 3.52e-03 1.46e-03 60.020 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: 136.064000 sec.
T50 in the 50-300 keV band: 77.120000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 305.472 -36.312 269.160
T90 269.952 -24.088 245.864
T50 101.760 15.272 117.032
Peak 1.000 52.372 53.372
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
346.7789 -68.1779 0.0193 38.5 -23.1 3.3515 10.0 TRIG_00332931
------------------------------------------
Foreground time interval of the image:
-36.312 269.160 (delta_t = 305.472 [sec])
Background time interval of the image:
-239.000 -36.312 (delta_t = 202.688 [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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -36.312 sec. to 269.160 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.43762 ( -0.180090 0.179665 )
Norm@50keV : 7.183438E-04 ( -7.583806E-05 7.557002E-05) )
------------------------------------------------------------
Chi-Squared = 50.67833 using 59 PHA bins.
Reduced chi-squared = 0.8890935 for 57 degrees of freedom
Null hypothesis probability = 0.710
Photon flux (15-150 keV) in 305.5 sec: 8.825782E-02 ( -0.00956611 0.00959106 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.10488e-06 ( -2.40545e-07 2.42396e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -36.312 sec. to 269.160 sec.
Parameters : value lower 90% higher 90%
Photon index: 0.959655 ( -0.853096 0.654645 )
Epeak [keV] : 110.022 ( -46.4906 9889.98 )
Norm@50keV : 1.248312E-03 ( -5.843687E-04 2.026869E-03) )
------------------------------------------------------------
Chi-Squared = 49.46909 using 59 PHA bins.
but latest trial 1.54217 gives Chi-Squared = 2.18085
but latest trial 48.3373 gives Chi-Squared = 16.4194
Reduced chi-squared = 0.8833765 for 56 degrees of freedom
Null hypothesis probability = 0.719
Photon flux (15-150 keV) in 305.5 sec: 8.650930E-02 ( -0.00996446 0.00994943 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03501e-06 ( -2.69084e-07 2.61312e-07 ) ergs/cm2
Band function
Time interval is from -36.312 sec. to 269.160 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.768489 ( -11.4115 2.21882 )
beta : -1.66066 ( -0.413305 0.302992 )
Epeak [keV] : 80.2738 ( -39.6754 420.375 )
Norm@50keV : 1.670967E-03 ( -1.009859E-02 9.51754 )
------------------------------------------------------------
Chi-Squared = 48.82964 using 59 PHA bins.
Reduced chi-squared = 0.8878115 for 55 degrees of freedom
Null hypothesis probability = 0.708
Photon flux (15-150 keV) in 305.5 sec: 8.575415E-02 ( -0.0101157 0.0096904 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03921e-06 ( -2.53076e-07 2.4093e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 52.392 sec. to 53.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.66466 ( -0.752231 0.835703 )
Norm@50keV : 3.511804E-03 ( -1.536408E-03 1.370056E-03) )
------------------------------------------------------------
Chi-Squared = 60.01849 using 59 PHA bins.
Reduced chi-squared = 1.052956 for 57 degrees of freedom
Null hypothesis probability = 0.367
Photon flux (15-150 keV) in 0.9600 sec: 0.460852 ( -0.169519 0.169643 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.13199e-08 ( -1.32848e-08 1.37507e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 52.392 sec. to 53.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.66393 ( -0.757125 0.839069 )
Epeak [keV] : 9992.00 ( -9991.99 8.00000 )
Norm@50keV : 3.518446E-03 ( -1.547721E-03 1.377821E-03) )
------------------------------------------------------------
Chi-Squared = 60.02049 using 59 PHA bins.
Reduced chi-squared = 1.071794 for 56 degrees of freedom
Null hypothesis probability = 0.332
Photon flux (15-150 keV) in 0.9600 sec: 0.460653 ( -0.169468 0.169591 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.12884e-08 ( -1.32598e-08 1.37826e-08 ) ergs/cm2
Band function
Time interval is from 52.392 sec. to 53.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.33196 ( -8.66804 6.33196 )
beta : -1.66438 ( -8.33562 0.752324 )
Epeak [keV] : 20.4335 ( -20.3335 9979.57 )
Norm@50keV : 8.321956E-03 ( -8.321956E-03 0.641529 )
------------------------------------------------------------
Chi-Squared = 60.01850 using 59 PHA bins.
Reduced chi-squared = 1.091246 for 55 degrees of freedom
Null hypothesis probability = 0.299
Photon flux (15-150 keV) in 0.9600 sec: 9.98306 ( -9.98306 10881.7 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.13009e-08 ( -1.13028e-08 1.29837e-08 ) ergs/cm2
Plot creation:
Wed Oct 29 10:48:10 EDT 2008