batgrbproduct Analysis for Trigger=306793
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): Thu Mar 20 02:45:39 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger306793/GCN5_download_cron
======================================================================
Trigger: 00306793 Segment: 000
BAT Trigger Time: 227639112 [s; MET]
Trigger Stop: 227639176 [s; MET]
UTC: 2008-03-19T17:05:09.345180 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 99.4803719736166 Dec: 23.9335194811168 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.22
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 7.22
Flight Position: [ source = BAT ]
RA: 99.4803719736166 Dec: 23.9335194811168 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 99.4801094074848 Dec: 23.9643361537032 [deg; J2000]
{ 06h 37m 55.2s , +23d 57' 51.6" }
+/- 2.68166581428596 [arcmin] (estimated 90% radius based on SNR)
+/- 1.12801827153751 [arcmin] (formal 1-sigma fit error)
SNR: 7.43210315743331
RA = 6h 37m 55.2s (99.480109 deg.)
Dec = 23d 57' 52" (23.964336 deg.)
Angular difference between Flight and Ground position is 1.849056 arcmin
Partial Coding Fraction: 0.59375 [ including projection effects ]
Duration
T90: 26.9120000004768 +/- 4.54080343748093
Measured from: 7.27200001478195
to: 34.1840000152588 [s; relative to TRIGTIME]
T50: 16.3440000116825 +/- 5.62053379547734
Measured from: 12.5999999940395
to: 28.944000005722 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 25.3479999899864
to: 26.3479999899864 [s; relative to TRIGTIME]
Total Fluence
Measured from: 5.33199998736382
to: 34.4760000109673 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.192598 0.234799 0.084869 0.041047
0.034686 0.035494 0.034406 0.036790 [error]
Peak 0.017231 -0.001800 0.005095 0.026185
0.006504 0.006538 0.006420 0.006958 [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 6.70e-08 9.27e-08 9.48e-08 1.77e-07 3.11e-07 4.30e-07 erg/cm2
Error 1.68e-08 1.77e-08 3.16e-08 1.17e-07 7.34e-08 1.53e-07 erg/cm2
Peak flux Power-law 4.43e-04 3.37e-03 2.29e-02 8.30e-01 8.21e-02 8.61e-01 ph/cm2/s
Error 6.80e-02 4.77e-02 4.57e-02 6.87e-01 1.40e-01 7.14e-01 ph/cm2/s
Fluence Cutoff-PL 6.13e-08 1.18e-07 4.94e-08 2.19e-09 2.31e-07 2.30e-07 erg/cm2
Error 1.93e-08 2.93e-08 4.75e-08 8.37e-08 8.00e-08 1.27e-07 erg/cm2
Peak flux Cutoff-PL 3.23e-04 2.76e-03 2.11e-02 9.27e-01 7.97e-02 9.53e-01 ph/cm2/s
Error 6.56e-02 4.64e-02 4.41e-02 7.39e-01 1.39e-01 7.63e-01 ph/cm2/s
Fluence Band 6.17e-08 1.13e-07 6.86e-08 5.34e-08 2.68e-07 3.12e-07 erg/cm2
Error 1.95e-08 2.66e-08 5.50e-08 5.44e-08 7.55e-08 1.22e-07 erg/cm2
Peak flux Band 4.81e-02 4.50e-02 5.31e-02 8.24e-01 5.49e-02 2.25e-01 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
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.966 0.352 - - 1.16e-03 2.84e-04 61.143 57
CPL -0.358 2.487 35.1 33.5 3.61e-02 0.00e+00 58.382 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL -1.596 3.109 - - 2.92e-04 1.21e-03 72.712 57
CPL -0.738 0.000 9998.5 5000.0 4.66e-04 1.09e-03 73.928 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 29.144 5.332 34.476
T90 26.912 7.272 34.184
T50 16.344 12.600 28.944
Peak 1.000 25.348 26.348
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
99.4801 +23.9643 0.0259 33.9 -141.4 0.5488 7.4 TRIG_00306793
------------------------------------------
Foreground time interval of the image:
5.332 34.476 (delta_t = 29.144 [sec])
Background time interval of the image:
-119.000 5.332 (delta_t = 124.332 [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 5.332 sec. to 34.476 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.96639 ( -0.336773 0.367001 )
Norm@50keV : 1.159418E-03 ( -2.876024E-04 2.796696E-04) )
------------------------------------------------------------
Chi-Squared = 61.14302 using 59 PHA bins.
Reduced chi-squared = 1.072685 for 57 degrees of freedom
Null hypothesis probability = 0.330
Photon flux (15-150 keV) in 29.14 sec: 0.171278 ( -0.031937 0.031939 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.11011e-07 ( -7.13496e-08 7.53881e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.332 sec. to 34.476 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.357917 ( -2.64208 2.33278 )
Epeak [keV] : 35.1112 ( -21.9206 44.9923 )
Norm@50keV : 3.607533E-02 ( )
------------------------------------------------------------
Chi-Squared = 58.38195 using 59 PHA bins.
but latest trial 80.0895 gives Chi-Squared = 2.89006
Reduced chi-squared = 1.042535 for 56 degrees of freedom
Null hypothesis probability = 0.388
Photon flux (15-150 keV) in 29.14 sec: 0.157032 ( -0.032242 0.034422 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.30725e-07 ( -5.607e-08 1.03899e-07 ) ergs/cm2
Band function
Time interval is from 5.332 sec. to 34.476 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.05781 ( -4.00792 2.51716 )
beta : -2.47333 ( -6.63786 1.23602 )
Epeak [keV] : 36.5385 ( -12.1240 18.2538 )
Norm@50keV : 4.554773E-03 ( -0.843115 33.3338 )
------------------------------------------------------------
Chi-Squared = 58.99425 using 59 PHA bins.
Reduced chi-squared = 1.072623 for 55 degrees of freedom
Null hypothesis probability = 0.332
Photon flux (15-150 keV) in 29.14 sec: 0.164568 ( -0.034187 0.030885 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.6846e-07 ( -7.86626e-08 7.24289e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 25.348 sec. to 26.348 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.59647 ( -1.40353 4.81464 )
Norm@50keV : 2.919056E-04 ( -2.919056E-04 2.123746E-03) )
------------------------------------------------------------
Chi-Squared = 72.71151 using 59 PHA bins.
Reduced chi-squared = 1.275640 for 57 degrees of freedom
Null hypothesis probability = 7.842E-02
Photon flux (15-150 keV) in 1.000 sec: 8.210241E-02 ( -0.0779991 0.201965 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.45246e-08 ( -1.45246e-08 1.97529e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 25.348 sec. to 26.348 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.737850 ( )
Epeak [keV] : 9998.53 ( -9998.52 1.47168 )
Norm@50keV : 4.659266E-04 ( -9.976821E-05 2.084943E-03) )
------------------------------------------------------------
Chi-Squared = 73.92817 using 59 PHA bins.
Reduced chi-squared = 1.320146 for 56 degrees of freedom
Null hypothesis probability = 5.452E-02
Photon flux (15-150 keV) in 1.000 sec: 7.974762E-02 ( -0.0797476 0.19756 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.43105e-08 ( -1.43105e-08 1.9749e-08 ) ergs/cm2
Band function
Time interval is from 25.348 sec. to 26.348 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.962539 ( -8.583069E-05 14.9999 )
beta : -1.02298 ( -4.88952 8.27240 )
Epeak [keV] : 17.6633 ( -17.5633 9982.34 )
Norm@50keV : 2.113282E-03 ( -3.183673E-02 0.294044 )
------------------------------------------------------------
Chi-Squared = 74.38805 using 59 PHA bins.
Reduced chi-squared = 1.352510 for 55 degrees of freedom
Null hypothesis probability = 4.188E-02
Photon flux (15-150 keV) in 1.000 sec: 5.486210E-02 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.30985e-08 ( 0 0 ) ergs/cm2
Plot creation:
Thu Mar 20 03:00:27 EDT 2008