batgrbproduct Analysis for Trigger=308196
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): Mon Mar 31 17:34:18 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger308196/GCN5_download_cron
======================================================================
Trigger: 00308196 Segment: 000
BAT Trigger Time: 228647016.128 [s; MET]
Trigger Stop: 228647017.152 [s; MET]
UTC: 2008-03-31T09:03:33.445180 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 266.80633737477 Dec: -27.362148564395 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 6.56
Image Trigger?: NO
Rate S/N Ratio: 10 [ if not an image trigger ]
Image S/N Ratio: 6.56
Flight Position: [ source = BAT ]
RA: 266.80633737477 Dec: -27.362148564395 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 266.788674910476 Dec: -27.3751424181546 [deg; J2000]
{ 17h 47m 09.3s , -27d 22' 30.5" }
+/- 2.70310931080709 [arcmin] (estimated 90% radius based on SNR)
+/- 1.61936870055465 [arcmin] (formal 1-sigma fit error)
SNR: 7.34802064641985
RA = 17h 47m 9.3s (266.788675 deg.)
Dec = -27d 22' 31" (-27.375142 deg.)
Angular difference between Flight and Ground position is 1.222107 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 13.4399999976158 +/- 2.22900155393154
Measured from: -11.2239999771118
to: 2.216000020504 [s; relative to TRIGTIME]
T50: 7.87200000882149 +/- 3.43966509651242
Measured from: -7.31999999284744
to: 0.552000015974045 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0439999997615814
to: 0.956000000238419 [s; relative to TRIGTIME]
Total Fluence
Measured from: -12.2479999959469
to: 3.56000000238419 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.350692 0.039837 -0.008853 -0.004347
0.024054 0.019924 0.017269 0.015798 [error]
Peak 0.055181 0.002750 -0.001546 0.003488
0.006252 0.004888 0.004357 0.003865 [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 1.02e-07 1.52e-08 1.04e-09 7.52e-11 1.18e-07 1.18e-07 erg/cm2
Error 1.62e-08 7.28e-09 1.35e-09 1.76e-10 2.05e-08 2.06e-08 erg/cm2
Peak flux Power-law 5.49e-01 5.88e-02 2.61e-03 1.21e-04 6.10e-01 6.10e-01 ph/cm2/s
Error 1.19e-01 3.81e-02 4.47e-03 4.32e-04 1.40e-01 1.40e-01 ph/cm2/s
Fluence Cutoff-PL 1.02e-07 1.52e-08 1.03e-09 7.46e-11 1.18e-07 1.18e-07 erg/cm2
Error 1.62e-08 7.27e-09 1.35e-09 1.74e-10 2.05e-08 2.06e-08 erg/cm2
Peak flux Cutoff-PL 5.48e-01 5.87e-02 2.60e-03 1.20e-04 6.09e-01 6.09e-01 ph/cm2/s
Error 1.19e-01 3.80e-02 4.46e-03 4.28e-04 1.40e-01 1.40e-01 ph/cm2/s
Fluence Band 9.99e-08 1.51e-08 1.03e-09 6.21e-11 1.19e-07 1.29e-07 erg/cm2
Error 1.59e-08 4.18e-09 1.06e-09 1.92e-08 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 5.48e-01 5.87e-02 2.60e-03 1.20e-04 6.09e-01 6.09e-01 ph/cm2/s
Error 1.19e-01 3.80e-02 4.46e-03 4.28e-04 1.40e-01 1.40e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 5.875 0.837 - - 6.80e-05 7.50e-05 60.253 57
CPL 1.580 0.000 1.9 5.6 3.33e-01 0.00e+00 59.275 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 5.217 1.219 - - 3.26e-04 3.52e-04 59.727 57
CPL 1.612 2.025 2.1 6.4 3.99e-01 6.35e+02 59.046 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 15.808 -12.248 3.560
T90 13.440 -11.224 2.216
T50 7.872 -7.320 0.552
Peak 1.000 -0.044 0.956
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
266.7887 -27.3751 0.0261 0.1 48.3 0.3202 7.3 TRIG_00308196
------------------------------------------
Foreground time interval of the image:
-12.248 3.560 (delta_t = 15.808 [sec])
Background time interval of the image:
-53.027 -12.248 (delta_t = 40.779 [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 -12.248 sec. to 3.560 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 5.87461 ( -0.786627 0.887743 )
Norm@50keV : 6.798216E-05 ( -6.798216E-05 8.204094E-05) )
------------------------------------------------------------
Chi-Squared = 60.25345 using 59 PHA bins.
Reduced chi-squared = 1.057078 for 57 degrees of freedom
Null hypothesis probability = 0.359
Photon flux (15-150 keV) in 15.81 sec: 0.246749 ( -0.039811 0.039813 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.17926e-07 ( -2.03799e-08 2.06901e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -12.248 sec. to 3.560 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.58014 ( )
Epeak [keV] : 1.87721 ( -3.09662 8.08249 )
Norm@50keV : 0.332650 ( )
------------------------------------------------------------
Chi-Squared = 59.27527 using 59 PHA bins.
but latest trial 11.1126 gives Chi-Squared = 6.91369
Reduced chi-squared = 1.058487 for 56 degrees of freedom
Null hypothesis probability = 0.357
Photon flux (15-150 keV) in 15.81 sec: 0.246458 ( -0.039777 0.039778 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.17854e-07 ( -2.03762e-08 2.06953e-08 ) ergs/cm2
Band function
Time interval is from -12.248 sec. to 3.560 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -9.07830 ( -0.921696 3.82172 )
beta : -5.87404 ( -0.888956 0.786079 )
Epeak [keV] : 271.541 ( -271.441 9728.46 )
Norm@50keV : 9.245085E-03 ( -5.736236E-03 1.114495E-02) )
------------------------------------------------------------
Chi-Squared = 60.25345 using 59 PHA bins.
Reduced chi-squared = 1.095517 for 55 degrees of freedom
Null hypothesis probability = 0.292
Photon flux (15-150 keV) in 15.81 sec: 0.164168 ( 1e+24 1e+24 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.19499e-07 ( -1.97813e-08 1.86164e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.024 sec. to 0.936 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 5.21666 ( -0.770745 1.66638 )
Norm@50keV : 3.261498E-04 ( -3.261498E-04 3.771219E-04) )
------------------------------------------------------------
Chi-Squared = 59.72650 using 59 PHA bins.
Reduced chi-squared = 1.047833 for 57 degrees of freedom
Null hypothesis probability = 0.377
Photon flux (15-150 keV) in 0.9600 sec: 0.610079 ( -0.140042 0.14014 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.80989e-08 ( -4.64131e-09 4.86269e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.024 sec. to 0.936 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.61182 ( -1.43040 2.61909 )
Epeak [keV] : 2.08444 ( -2.07444 10.6869 )
Norm@50keV : 0.399200 ( -0.399200 1269.02 )
------------------------------------------------------------
Chi-Squared = 59.04551 using 59 PHA bins.
but latest trial 12.7713 gives Chi-Squared = 1.03891
Reduced chi-squared = 1.054384 for 56 degrees of freedom
Null hypothesis probability = 0.365
Photon flux (15-150 keV) in 0.9600 sec: 0.609446 ( -0.139975 0.140069 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.80915e-08 ( -4.63718e-09 4.86912e-09 ) ergs/cm2
Band function
Time interval is from -0.024 sec. to 0.936 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -9.31396 ( -0.686038 8.21603 )
beta : -5.49236 ( -1.34217 1.01838 )
Epeak [keV] : 352.957 ( -352.857 9647.04 )
Norm@50keV : 3.336029E-02 ( -3.336029E-02 5.972853E-02) )
------------------------------------------------------------
Chi-Squared = 59.55902 using 59 PHA bins.
Reduced chi-squared = 1.082891 for 55 degrees of freedom
Null hypothesis probability = 0.313
Photon flux (15-150 keV) in 0.9600 sec: 0.609444 ( -0.139974 0.140072 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.79942e-08 ( -4.48493e-09 3.90259e-09 ) ergs/cm2
Plot creation:
Mon Mar 31 18:10:22 EDT 2008