batgrbproduct Analysis for Trigger=312068
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 May 21 16:54:38 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger312068/GCN5_download_cron
======================================================================
Trigger: 00312068 Segment: 000
BAT Trigger Time: 233042624 [s; MET]
Trigger Stop: 233042688 [s; MET]
UTC: 2008-05-21T06:03:41.193860 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 252.010523081687 Dec: -45.1573313426522 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 7.21
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 7.21
Flight Position: [ source = BAT ]
RA: 252.010523081687 Dec: -45.1573313426522 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 252.089414340535 Dec: -45.1388786819742 [deg; J2000]
{ 16h 48m 21.5s , -45d 08' 20.0" }
+/- 3.34200626097183 [arcmin] (estimated 90% radius based on SNR)
+/- 2.49589240470592 [arcmin] (formal 1-sigma fit error)
SNR: 5.42670959258709
Angular difference between Flight and Ground position is 3.517212 arcmin
Partial Coding Fraction: 0.703125 [ including projection effects ]
Duration
T90: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
T50: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 64 second)
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.272532 0.235267 0.011627 0.030197
0.050803 0.048687 0.042650 0.038626 [error]
Peak 0.272532 0.235267 0.011627 0.030197
0.050803 0.048687 0.042650 0.038626 [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 7.52e-08 8.47e-08 6.82e-08 9.15e-08 2.62e-07 3.19e-07 erg/cm2
Error 2.27e-08 2.35e-08 3.55e-08 9.06e-08 8.42e-08 1.43e-07 erg/cm2
Peak flux Power-law 3.85e-02 2.41e-02 9.72e-03 5.29e-03 7.51e-02 7.77e-02 ph/cm2/s
Error 1.19e-02 6.50e-03 4.89e-03 5.92e-03 1.87e-02 1.97e-02 ph/cm2/s
Fluence Cutoff-PL 7.66e-08 1.01e-07 1.85e-08 1.52e-10 1.97e-07 1.96e-07 erg/cm2
Error 2.58e-08 3.41e-08 4.09e-08 6.13e-08 7.33e-08 1.12e-07 erg/cm2
Peak flux Cutoff-PL 3.82e-02 2.97e-02 3.04e-03 1.36e-05 7.09e-02 7.09e-02 ph/cm2/s
Error 1.34e-02 9.39e-03 5.86e-03 3.50e-03 1.78e-02 1.78e-02 ph/cm2/s
Fluence Band 7.78e-08 9.34e-08 4.70e-08 1.21e-08 2.21e-07 2.53e-07 erg/cm2
Error 2.88e-08 2.80e-08 6.93e-08 9.44e-08 1.13e-07 0.00e+00 erg/cm2
Peak flux Band 3.74e-02 2.82e-02 6.53e-03 1.34e-03 7.41e-02 7.43e-02 ph/cm2/s
Error 1.36e-02 7.92e-03 3.66e-03 2.83e-03 1.83e-02 1.88e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.312 0.512 - - 4.27e-04 1.65e-04 60.184 57
CPL -0.740 2.912 26.5 17.9 5.93e-02 6.53e-01 57.821 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.312 0.512 - - 4.27e-04 1.65e-04 60.184 57
CPL -0.740 2.506 26.5 17.9 5.93e-02 6.53e-01 57.821 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 64.000 0.000 64.000
T90 64.000 0.000 64.000
T50 64.000 0.000 64.000
Peak 64.000 0.000 64.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
252.0894 -45.1389 0.0356 20.3 64.1 0.5166 5.4 TRIG_00312068
------------------------------------------
Foreground time interval of the image:
0.000 64.000 (delta_t = 64.000 [sec])
Background time interval of the image:
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 0.000 sec. to 64.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.31175 ( -0.475486 0.547951 )
Norm@50keV : 4.273176E-04 ( -1.645723E-04 1.648573E-04) )
------------------------------------------------------------
Chi-Squared = 60.18392 using 59 PHA bins.
Reduced chi-squared = 1.055858 for 57 degrees of freedom
Null hypothesis probability = 0.361
Photon flux (15-150 keV) in 64.00 sec: 7.510207E-02 ( -0.0186995 0.0187147 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.61721e-07 ( -8.04051e-08 8.7961e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.740392 ( -2.25961 3.56372 )
Epeak [keV] : 26.5347 ( -26.5247 9.22951 )
Norm@50keV : 5.925614E-02 ( -5.925614E-02 1.24629 )
------------------------------------------------------------
Chi-Squared = 57.82116 using 59 PHA bins.
Reduced chi-squared = 1.032521 for 56 degrees of freedom
Null hypothesis probability = 0.408
Photon flux (15-150 keV) in 64.00 sec: 7.091190E-02 ( -0.0176354 0.0178986 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.9664e-07 ( -5.41523e-08 9.23808e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.38326 ( -14.9388 8.248806E-03) )
beta : -2.77535 ( -1.55237 0.668922 )
Epeak [keV] : 21.9168 ( -6.19951 80.9068 )
Norm@50keV : 1.791787E-03 ( -243.858 1720.38 )
------------------------------------------------------------
Chi-Squared = 58.88899 using 59 PHA bins.
Reduced chi-squared = 1.070709 for 55 degrees of freedom
Null hypothesis probability = 0.335
Photon flux (15-150 keV) in 64.00 sec: 7.407068E-02 ( -0.0180912 0.0184504 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.20551e-07 ( -7.3591e-08 1.15259e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.31175 ( -0.475486 0.547951 )
Norm@50keV : 4.273176E-04 ( -1.645723E-04 1.648573E-04) )
------------------------------------------------------------
Chi-Squared = 60.18392 using 59 PHA bins.
Reduced chi-squared = 1.055858 for 57 degrees of freedom
Null hypothesis probability = 0.361
Photon flux (15-150 keV) in 64.00 sec: 7.510207E-02 ( -0.0186995 0.0187147 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.61721e-07 ( -8.04051e-08 8.7961e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 64.000 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.740392 ( -2.25961 2.75235 )
Epeak [keV] : 26.5347 ( -26.5247 9.22951 )
Norm@50keV : 5.925614E-02 ( -5.925614E-02 1.24629 )
------------------------------------------------------------
Chi-Squared = 57.82116 using 59 PHA bins.
but latest trial 2.03256 gives Chi-Squared = 3.30130
Reduced chi-squared = 1.032521 for 56 degrees of freedom
Null hypothesis probability = 0.408
Photon flux (15-150 keV) in 64.00 sec: 7.091190E-02 ( -0.0176354 0.0178986 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.9664e-07 ( -5.41523e-08 9.23808e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.38326 ( -14.9389 8.248806E-03) )
beta : -2.77535 ( -1.55237 0.668922 )
Epeak [keV] : 21.9168 ( -6.20832 80.9068 )
Norm@50keV : 1.791787E-03 ( -243.858 1720.38 )
------------------------------------------------------------
Chi-Squared = 58.88899 using 59 PHA bins.
Reduced chi-squared = 1.070709 for 55 degrees of freedom
Null hypothesis probability = 0.335
Photon flux (15-150 keV) in 64.00 sec: 7.407068E-02 ( -0.0180912 0.0184504 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.20551e-07 ( -7.3591e-08 1.15259e-07 ) ergs/cm2
Plot creation:
Wed May 21 17:31:26 EDT 2008