batgrbproduct Analysis for Trigger=230702
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 Jan 2 05:39:40 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger230702/GCN5_download_cron
======================================================================
Trigger: 00230702 Segment: 000
BAT Trigger Time: 180704287.68 [s; MET]
Trigger Stop: 180704291.776 [s; MET]
UTC: 2006-09-23T11:38:06.217800 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 238.201486511859 Dec: -30.9072142492461 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.4
Image Trigger?: NO
Rate S/N Ratio: 10.3923048454133 [ if not an image trigger ]
Image S/N Ratio: 9.4
Flight Position: [ source = BAT ]
RA: 238.201486511859 Dec: -30.9072142492461 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 238.190125151208 Dec: -30.9054877423928 [deg; J2000]
{ 15h 52m 45.6s , -30d 54' 19.8" }
+/- 1.66640462315482 [arcmin] (estimated 90% radius based on SNR)
+/- 0.831948367932403 [arcmin] (formal 1-sigma fit error)
SNR: 14.6652391259571
RA = 15h 52m 45.6s (238.190125 deg.)
Dec = -30d 54' 20" (-30.905488 deg.)
Angular difference between Flight and Ground position is 0.593991 arcmin
Partial Coding Fraction: 0.3632812 [ including projection effects ]
Duration
T90: 7.86800000071526 +/- 1.22196235626248
Measured from: 1.22400000691414
to: 9.09200000762939 [s; relative to TRIGTIME]
T50: 4.27600002288818 +/- 1.06782772862463
Measured from: 2.34399998188019
to: 6.62000000476837 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 4.92800000309944
to: 5.92800000309944 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0680000185966492
to: 9.78799998760223 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.403882 0.346808 0.107365 0.028856
0.035963 0.032907 0.028825 0.027631 [error]
Peak 0.069315 0.051735 0.020041 0.002455
0.011853 0.010603 0.009304 0.008464 [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 1.59e-07 1.59e-07 1.12e-07 1.26e-07 4.80e-07 5.56e-07 erg/cm2
Error 2.42e-08 1.90e-08 2.66e-08 5.72e-08 6.20e-08 9.29e-08 erg/cm2
Peak flux Power-law 8.55e-01 4.68e-01 1.61e-01 7.18e-02 1.52e+00 1.56e+00 ph/cm2/s
Error 2.33e-01 1.07e-01 6.98e-02 5.75e-02 3.25e-01 3.31e-01 ph/cm2/s
Fluence Cutoff-PL 1.53e-07 1.70e-07 1.03e-07 4.08e-08 4.53e-07 4.65e-07 erg/cm2
Error 2.66e-08 2.52e-08 3.44e-08 8.71e-08 7.26e-08 1.23e-07 erg/cm2
Peak flux Cutoff-PL 7.97e-01 5.39e-01 1.28e-01 9.13e-03 1.47e+00 1.47e+00 ph/cm2/s
Error 2.58e-01 1.46e-01 9.91e-02 5.72e-02 3.32e-01 3.35e-01 ph/cm2/s
Fluence Band 1.57e-07 1.62e-07 1.09e-07 1.15e-07 4.75e-07 6.21e-07 erg/cm2
Error 2.45e-08 1.91e-08 2.13e-08 4.37e-08 5.49e-08 0.00e+00 erg/cm2
Peak flux Band 7.99e-01 5.39e-01 1.28e-01 9.19e-03 1.47e+00 1.47e+00 ph/cm2/s
Error 1.93e-01 1.24e-01 4.20e-02 5.74e-02 2.42e-01 3.12e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.505 0.246 - - 4.87e-03 8.36e-04 56.851 57
CPL 1.865 0.705 7.9 14.3 1.20e-02 3.41e-02 55.776 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.543 0.449 - - 7.55e-03 2.52e-03 46.922 57
CPL 1.072 3.066 22.1 17.5 6.57e-02 1.11e+01 45.356 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 9.856 -0.068 9.788
T90 7.868 1.224 9.092
T50 4.276 2.344 6.620
Peak 1.000 4.928 5.928
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
238.1901 -30.9055 0.0131 46.1 -156.9 0.9444 14.7 TRIG_00230702
------------------------------------------
Foreground time interval of the image:
-0.068 9.788 (delta_t = 9.856 [sec])
Background time interval of the image:
-239.680 -0.068 (delta_t = 239.612 [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 -0.068 sec. to 9.788 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.50463 ( -0.235806 0.255417 )
Norm@50keV : 4.867162E-03 ( -8.443343E-04 8.277353E-04) )
------------------------------------------------------------
Chi-Squared = 56.85117 using 59 PHA bins.
Reduced chi-squared = 0.9973890 for 57 degrees of freedom
Null hypothesis probability = 0.481
Photon flux (15-150 keV) in 9.856 sec: 0.958850 ( -0.108979 0.10913 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.80213e-07 ( -6.12324e-08 6.27413e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.068 sec. to 9.788 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.86479 ( -1.27246 0.137333 )
Epeak [keV] : 7.91736 ( -7.52601 21.0186 )
Norm@50keV : 1.201553E-02 ( -4.257776E-03 6.390788E-02) )
------------------------------------------------------------
Chi-Squared = 55.77579 using 59 PHA bins.
but latest trial 1.99582 gives Chi-Squared = 1.94453
but latest trial -0.451103 gives Chi-Squared = 0.409840
Reduced chi-squared = 0.9959963 for 56 degrees of freedom
Null hypothesis probability = 0.483
Photon flux (15-150 keV) in 9.856 sec: 0.936644 ( -0.115015 0.114626 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.53303e-07 ( -6.94434e-08 7.58281e-08 ) ergs/cm2
Band function
Time interval is from -0.068 sec. to 9.788 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.61612 ( -8.38388 2.02383 )
beta : -2.98072 ( -7.01928 0.643636 )
Epeak [keV] : 14.9731 ( -14.8731 13.1220 )
Norm@50keV : 1.792373E-02 ( -1.792373E-02 1908.52 )
------------------------------------------------------------
Chi-Squared = 55.60459 using 59 PHA bins.
Reduced chi-squared = 1.010993 for 55 degrees of freedom
Null hypothesis probability = 0.452
Photon flux (15-150 keV) in 9.856 sec: 0.928625 ( -0.109081 0.122195 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.75467e-07 ( -5.35506e-08 5.61654e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 4.928 sec. to 5.928 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.54284 ( -0.412952 0.485140 )
Norm@50keV : 7.550648E-03 ( -2.530038E-03 2.503122E-03) )
------------------------------------------------------------
Chi-Squared = 46.92156 using 59 PHA bins.
Reduced chi-squared = 0.8231853 for 57 degrees of freedom
Null hypothesis probability = 0.827
Photon flux (15-150 keV) in 1.000 sec: 1.52310 ( -0.32473 0.32496 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.6392e-08 ( -1.86959e-08 1.96119e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.928 sec. to 5.928 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.07222 ( -4.07222 2.05996 )
Epeak [keV] : 22.0855 ( -21.1025 13.8480 )
Norm@50keV : 6.573355E-02 ( -6.573355E-02 22.2263 )
------------------------------------------------------------
Chi-Squared = 45.35595 using 59 PHA bins.
but latest trial 0.979286 gives Chi-Squared = 0.462856
Reduced chi-squared = 0.8099278 for 56 degrees of freedom
Null hypothesis probability = 0.845
Photon flux (15-150 keV) in 1.000 sec: 1.47154 ( -0.33279 0.33201 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.85963e-08 ( -1.83581e-08 2.11025e-08 ) ergs/cm2
Band function
Time interval is from 4.928 sec. to 5.928 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.56159 ( -8.43841 2.45915 )
beta : -9.35234 ( -0.647663 19.3523 )
Epeak [keV] : 16.3192 ( -16.2192 19.9788 )
Norm@50keV : 3.117500E-02 ( -1.71741 1120.32 )
------------------------------------------------------------
Chi-Squared = 45.48045 using 59 PHA bins.
Reduced chi-squared = 0.8269174 for 55 degrees of freedom
Null hypothesis probability = 0.816
Photon flux (15-150 keV) in 1.000 sec: 1.47116 ( -0.31694 0.16695 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.81621e-08 ( -1.64561e-08 1.5746e-08 ) ergs/cm2
Plot creation:
Wed Jan 2 06:09:21 EST 2008