batgrbproduct Analysis for Trigger=306829
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 10:01:00 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger306829/GCN5_download_cron
======================================================================
Trigger: 00306829 Segment: 000
BAT Trigger Time: 227659488 [s; MET]
Trigger Stop: 227659552 [s; MET]
UTC: 2008-03-19T22:44:45.344620 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 252.002678827311 Dec: -45.1717800458437 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.02
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 12.02
Flight Position: [ source = BAT ]
RA: 252.002678827311 Dec: -45.1717800458437 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 251.817466385136 Dec: -45.0870259669037 [deg; J2000]
{ 16h 47m 16.2s , -45d 05' 13.3" }
+/- 5.50086093993599 [arcmin] (estimated 90% radius based on SNR)
+/- 4.07124423504392 [arcmin] (formal 1-sigma fit error)
SNR: 2.662933280237
RA = 16h 47m 16.2s (251.817466 deg.)
Dec = -45d 5' 13" (-45.087026 deg.)
Angular difference between Flight and Ground position is 9.344908 arcmin
Partial Coding Fraction: 1 [ including projection effects ]
Duration
T90: 55.6520000100136 +/- 37.8739097576011
Measured from: -70.6520000100136
to: -15 [s; relative to TRIGTIME]
T50: 30.0079999864101 +/- 37.8582850306054
Measured from: -67.9359999895096
to: -37.9280000030994 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -70.7579999864101
to: -69.7579999864101 [s; relative to TRIGTIME]
Total Fluence
Measured from: -70.7039999961853
to: -0.916000008583069 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.405696 0.251787 0.142894 -0.031844
0.065382 0.059744 0.050812 0.043847 [error]
Peak 0.021081 0.031689 0.045879 0.003575
0.015174 0.015200 0.013410 0.011504 [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 1.19e-07 1.02e-07 6.01e-08 5.29e-08 3.04e-07 3.33e-07 erg/cm2
Error 3.05e-08 3.15e-08 3.90e-08 6.74e-08 9.34e-08 1.31e-07 erg/cm2
Peak flux Power-law 1.07e-01 1.78e-01 2.24e-01 5.66e-01 6.67e-01 1.07e+00 ph/cm2/s
Error 1.61e-01 1.47e-01 1.63e-01 7.92e-01 3.66e-01 6.53e-01 ph/cm2/s
Fluence Cutoff-PL 1.19e-07 1.02e-07 6.00e-08 5.25e-08 3.04e-07 3.34e-07 erg/cm2
Error 3.05e-08 3.16e-08 3.90e-08 6.68e-08 9.34e-08 1.31e-07 erg/cm2
Peak flux Cutoff-PL 1.06e-01 1.77e-01 2.25e-01 5.63e-01 6.66e-01 1.07e+00 ph/cm2/s
Error 1.60e-01 1.47e-01 1.64e-01 7.90e-01 3.66e-01 4.91e-01 ph/cm2/s
Fluence Band 1.20e-07 1.01e-07 5.68e-08 4.73e-08 3.00e-07 3.29e-07 erg/cm2
Error 3.08e-08 2.99e-08 3.37e-08 3.96e-08 7.78e-08 0.00e+00 erg/cm2
Peak flux Band 1.27e-01 1.88e-01 2.24e-01 5.80e-01 6.62e-01 9.89e-01 ph/cm2/s
Error 1.01e-01 1.02e-01 3.73e-01 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 2.764 0.614 - - 4.00e-04 1.92e-04 59.071 57
CPL 1.932 1.168 2.8 21.4 1.38e-03 2.88e-02 60.052 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.664 1.209 - - 5.75e-03 3.57e-03 76.313 57
CPL 0.652 1.223 9988.2 5000.0 5.79e-03 3.59e-03 76.318 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 69.788 -70.704 -0.916
T90 55.652 -70.652 -15.000
T50 30.008 -67.936 -37.928
Peak 1.000 -70.758 -69.758
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
251.8175 -45.0870 0.0718 0.2 109.5 0.0568 2.7 TRIG_00306829
------------------------------------------
Foreground time interval of the image:
-6.799 -0.916 (delta_t = 5.883 [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 -70.704 sec. to -0.916 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.76384 ( -0.538948 0.688318 )
Norm@50keV : 3.996192E-04 ( -1.872688E-04 1.961658E-04) )
------------------------------------------------------------
Chi-Squared = 59.07099 using 59 PHA bins.
Reduced chi-squared = 1.036333 for 57 degrees of freedom
Null hypothesis probability = 0.400
Photon flux (15-150 keV) in 69.79 sec: 9.313123E-02 ( -0.0207264 0.0207688 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.03621e-07 ( -8.85314e-08 9.8205e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -70.704 sec. to -0.916 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.93180 ( -2.05223 0.282885 )
Epeak [keV] : 2.76522 ( -2.59945 40.2122 )
Norm@50keV : 1.376384E-03 ( -1.376384E-03 5.625515E-02) )
------------------------------------------------------------
Chi-Squared = 60.05175 using 59 PHA bins.
but latest trial -2.96073 gives Chi-Squared = 2.56115
but latest trial 73.2025 gives Chi-Squared = 3.80135
Reduced chi-squared = 1.072353 for 56 degrees of freedom
Null hypothesis probability = 0.331
Photon flux (15-150 keV) in 69.79 sec: 9.309200E-02 ( -0.0207192 0.020761 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.03559e-07 ( -8.85077e-08 9.82085e-08 ) ergs/cm2
Band function
Time interval is from -70.704 sec. to -0.916 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.74982 ( -9.30449 5.69551 )
beta : -9.21920 ( -0.911664 0.538370 )
Epeak [keV] : 10.3286 ( -10.2283 12.6115 )
Norm@50keV : 1.552898E-03 ( -3.193370E-02 92.4542 )
------------------------------------------------------------
Chi-Squared = 60.55571 using 59 PHA bins.
Reduced chi-squared = 1.101013 for 55 degrees of freedom
Null hypothesis probability = 0.282
Photon flux (15-150 keV) in 69.79 sec: 9.309187E-02 ( -0.0207191 0.0207611 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.99792e-07 ( -8.53392e-08 7.02925e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -70.704 sec. to -69.812 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.664063 ( -1.35414 1.06399 )
Norm@50keV : 5.751332E-03 ( -3.867274E-03 3.279643E-03) )
------------------------------------------------------------
Chi-Squared = 76.31336 using 59 PHA bins.
Reduced chi-squared = 1.338831 for 57 degrees of freedom
Null hypothesis probability = 4.473E-02
Photon flux (15-150 keV) in 0.8920 sec: 0.666872 ( -0.353621 0.378168 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.36459e-08 ( -2.94153e-08 2.93085e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -70.704 sec. to -69.812 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.652493 ( -1.37091 1.07479 )
Epeak [keV] : 9988.23 ( -9988.22 11.7676 )
Norm@50keV : 5.791446E-03 ( -3.885404E-03 3.290247E-03) )
------------------------------------------------------------
Chi-Squared = 76.31774 using 59 PHA bins.
Reduced chi-squared = 1.362817 for 56 degrees of freedom
Null hypothesis probability = 3.686E-02
Photon flux (15-150 keV) in 0.8920 sec: 0.666246 ( -0.353187 0.378104 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.36754e-08 ( -2.94599e-08 2.93566e-08 ) ergs/cm2
Band function
Time interval is from -70.704 sec. to -69.812 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.844226 ( -9.15577 5.84423 )
beta : -0.666283 ( -1.06178 1.35644 )
Epeak [keV] : 13.4148 ( -13.3148 9986.58 )
Norm@50keV : 8.776452E-03 ( -8.776451E-03 170717. )
------------------------------------------------------------
Chi-Squared = 76.31341 using 59 PHA bins.
Reduced chi-squared = 1.387516 for 55 degrees of freedom
Null hypothesis probability = 3.016E-02
Photon flux (15-150 keV) in 0.8920 sec: 0.661906 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 5.57625e-08 ( -2.56852e-08 2.56944e-08 ) ergs/cm2
Plot creation:
Thu Mar 20 10:16:50 EDT 2008