batgrbproduct Analysis for Trigger=158855
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 9 15:43:07 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger158855/SDC
======================================================================
Trigger: 00158855 Segment: 000
BAT Trigger Time: 150482001.088 [s; MET]
Trigger Stop: 150482002.112 [s; MET]
UTC: 2005-10-08T16:33:21.316200 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 202.870241770763 Dec: 42.0905012677457 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.65
Image Trigger?: NO
Rate S/N Ratio: 17.1464281994822 [ if not an image trigger ]
Image S/N Ratio: 9.65
Flight Position: [ source = BAT ]
RA: 202.870241770763 Dec: 42.0905012677457 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 202.865180117416 Dec: 42.1001150222164 [deg; J2000]
{ 13h 31m 27.6s , +42d 06' 00.4" }
+/- 0.722839125965228 [arcmin] (estimated 90% radius based on SNR)
+/- 0.204995804920711 [arcmin] (formal 1-sigma fit error)
SNR: 48.3601287503747
RA = 13h 31m 27.6s (202.865180 deg.)
Dec = 42d 6' 0" (42.100115 deg.)
Angular difference between Flight and Ground position is 0.619283 arcmin
Partial Coding Fraction: 0.375 [ including projection effects ]
Duration
T90: 12.4000000059605 +/- 1.30963811646047
Measured from: -1.55599999427795
to: 10.8440000116825 [s; relative to TRIGTIME]
T50: 4.74799999594688 +/- 0.414921660601174
Measured from: 2.26399999856949
to: 7.01199999451637 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 2.8759999871254
to: 3.8759999871254 [s; relative to TRIGTIME]
Total Fluence
Measured from: -24.9320000112057
to: 13.2560000121593 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.199826 2.184693 2.493109 0.816529
0.062452 0.059123 0.055328 0.045428 [error]
Peak 0.117811 0.203475 0.249476 0.084477
0.011774 0.012525 0.012951 0.010627 [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 4.42e-07 1.02e-06 1.87e-06 8.20e-06 5.09e-06 1.15e-05 erg/cm2
Error 2.98e-08 4.05e-08 5.50e-08 5.84e-07 1.45e-07 0.00e+00 erg/cm2
Peak flux Power-law 1.25e+00 1.66e+00 1.61e+00 2.80e+00 5.44e+00 7.32e+00 ph/cm2/s
Error 1.69e-01 1.34e-01 1.01e-01 3.93e-01 3.50e-01 4.59e-01 ph/cm2/s
Fluence Cutoff-PL 4.02e-07 1.03e-06 1.94e-06 6.04e-06 5.06e-06 8.81e-06 erg/cm2
Error 4.11e-08 4.20e-08 7.49e-08 1.39e-06 1.48e-07 0.00e+00 erg/cm2
Peak flux Cutoff-PL 1.18e+00 1.67e+00 1.66e+00 2.34e+00 5.39e+00 6.80e+00 ph/cm2/s
Error 2.22e-01 1.39e-01 1.36e-01 7.49e-01 3.62e-01 8.38e-01 ph/cm2/s
Fluence Band 3.98e-07 1.02e-06 1.94e-06 6.03e-06 5.06e-06 9.15e-06 erg/cm2
Error 4.07e-08 4.19e-08 7.50e-08 1.39e-06 1.48e-07 0.00e+00 erg/cm2
Peak flux Band 1.17e+00 1.67e+00 1.66e+00 2.34e+00 5.39e+00 7.30e+00 ph/cm2/s
Error 2.21e-01 1.39e-01 1.36e-01 7.49e-01 3.62e-01 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.126 0.054 - - 1.29e-02 3.88e-04 54.969 57
CPL 0.832 0.228 253.1 300.3 1.68e-02 3.46e-03 49.791 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.041 0.110 - - 4.71e-02 2.91e-03 52.104 57
CPL 0.849 0.373 373.2 5000.0 5.66e-02 2.10e-02 51.392 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: 16.512000 sec.
T50 in the 50-300 keV band: 5.312000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 38.188 -24.932 13.256
T90 12.400 -1.556 10.844
T50 4.748 2.264 7.012
Peak 1.000 2.876 3.876
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
202.8652 +42.1001 0.0040 44.0 -28.7 6.9376 48.4 TRIG_00158855
------------------------------------------
Foreground time interval of the image:
-24.932 13.256 (delta_t = 38.188 [sec])
Background time interval of the image:
-299.088 -24.932 (delta_t = 274.156 [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 -24.932 sec. to 13.256 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.12603 ( -5.395854E-02 5.346012E-02) )
Norm@50keV : 1.285889E-02 ( -3.887862E-04 3.871806E-04) )
------------------------------------------------------------
Chi-Squared = 54.96866 using 59 PHA bins.
Reduced chi-squared = 0.9643624 for 57 degrees of freedom
Null hypothesis probability = 0.552
Photon flux (15-150 keV) in 38.19 sec: 1.49553 ( -0.04895 0.04917 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.0926e-06 ( -1.4474e-07 1.44702e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -24.932 sec. to 13.256 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.831601 ( -0.235341 0.221154 )
Epeak [keV] : 253.098 ( -83.8625 516.785 )
Norm@50keV : 1.681909E-02 ( -3.021063E-03 3.893271E-03) )
------------------------------------------------------------
Chi-Squared = 49.79086 using 59 PHA bins.
Reduced chi-squared = 0.8891225 for 56 degrees of freedom
Null hypothesis probability = 0.708
Photon flux (15-150 keV) in 38.19 sec: 1.46767 ( -0.05251 0.05279 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.0601e-06 ( -1.4875e-07 1.47566e-07 ) ergs/cm2
Band function
Time interval is from -24.932 sec. to 13.256 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.831177 ( -0.222097 0.234946 )
beta : -8.95201 ( -1.04799 7.76632 )
Epeak [keV] : 252.781 ( -83.5115 516.404 )
Norm@50keV : 1.682481E-02 ( -3.028389E-03 3.887506E-03) )
------------------------------------------------------------
Chi-Squared = 49.79103 using 59 PHA bins.
Reduced chi-squared = 0.9052914 for 55 degrees of freedom
Null hypothesis probability = 0.673
Photon flux (15-150 keV) in 38.19 sec: 1.46770 ( -0.05254 0.05289 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.05651e-06 ( -1.48712e-07 1.48101e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 2.876 sec. to 3.876 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.04099 ( -0.110884 0.109152 )
Norm@50keV : 4.713099E-02 ( -2.919819E-03 2.905019E-03) )
------------------------------------------------------------
Chi-Squared = 52.10406 using 59 PHA bins.
Reduced chi-squared = 0.9141062 for 57 degrees of freedom
Null hypothesis probability = 0.659
Photon flux (15-150 keV) in 1.000 sec: 5.44000 ( -0.34997 0.35048 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.02412e-07 ( -3.1481e-08 3.1632e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.876 sec. to 3.876 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.849306 ( -0.465940 0.281029 )
Epeak [keV] : 373.181 ( -373.171 9626.82 )
Norm@50keV : 5.656968E-02 ( -1.170466E-02 3.021274E-02) )
------------------------------------------------------------
Chi-Squared = 51.39235 using 59 PHA bins.
Reduced chi-squared = 0.9177206 for 56 degrees of freedom
Null hypothesis probability = 0.650
Photon flux (15-150 keV) in 1.000 sec: 5.39192 ( -0.36074 0.3624 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.00863e-07 ( -3.149e-08 3.1953e-08 ) ergs/cm2
Band function
Time interval is from 2.876 sec. to 3.876 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.840572 ( -9.15943 5.83846 )
beta : -1.04099 ( -0.109132 0.110884 )
Epeak [keV] : 57.1056 ( -57.0056 9942.89 )
Norm@50keV : 7.971886E-02 ( -1.52549 1139.43 )
------------------------------------------------------------
Chi-Squared = 52.10406 using 59 PHA bins.
Reduced chi-squared = 0.9473465 for 55 degrees of freedom
Null hypothesis probability = 0.586
Photon flux (15-150 keV) in 1.000 sec: 5.39215 ( -0.36161 0.36296 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.00527e-07 ( -3.2094e-08 3.1997e-08 ) ergs/cm2
Plot creation:
Wed Jan 9 15:51:29 EST 2008