batgrbproduct Analysis for Trigger=181156
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 Dec 31 12:25:22 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger181156/SDC
======================================================================
Trigger: 00181156 Segment: 000
BAT Trigger Time: 161366115.776 [s; MET]
Trigger Stop: 161366117.824 [s; MET]
UTC: 2006-02-11T15:55:14.766340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 75.0691948313119 Dec: 14.9576753746448 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.03
Image Trigger?: NO
Rate S/N Ratio: 12.0415945787923 [ if not an image trigger ]
Image S/N Ratio: 9.03
Flight Position: [ source = BAT ]
RA: 75.0691948313119 Dec: 14.9576753746448 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 75.0826832160545 Dec: 14.9650415930742 [deg; J2000]
{ 05h 00m 19.8s , +14d 57' 54.1" }
+/- 1.91486017043637 [arcmin] (estimated 90% radius based on SNR)
+/- 0.903381245791206 [arcmin] (formal 1-sigma fit error)
SNR: 12.02445575944
RA = 5h 0m 19.8s (75.082683 deg.)
Dec = 14d 57' 54" (14.965042 deg.)
Angular difference between Flight and Ground position is 0.898141 arcmin
Partial Coding Fraction: 0.828125 [ including projection effects ]
Duration
T90: 28.7360000312328 +/- 5.01083626545441
Measured from: -9.85600000619888
to: 18.880000025034 [s; relative to TRIGTIME]
T50: 8.32000002264977 +/- 5.23784381324225
Measured from: -0.57600000500679
to: 7.74400001764297 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.77200001478195
to: 2.77200001478195 [s; relative to TRIGTIME]
Total Fluence
Measured from: -10.7520000040531
to: 21.6319999992847 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.206360 0.281331 0.211070 0.056454
0.030193 0.030557 0.026555 0.022683 [error]
Peak 0.021256 0.033133 0.025345 0.009205
0.005323 0.005555 0.004790 0.003847 [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 6.42e-08 1.16e-07 1.62e-07 4.70e-07 4.65e-07 8.15e-07 erg/cm2
Error 1.26e-08 1.40e-08 2.61e-08 1.63e-07 6.25e-08 1.84e-07 erg/cm2
Peak flux Power-law 2.23e-01 2.33e-01 1.73e-01 2.07e-01 7.09e-01 8.36e-01 ph/cm2/s
Error 6.93e-02 4.60e-02 4.00e-02 9.75e-02 1.32e-01 1.58e-01 ph/cm2/s
Fluence Cutoff-PL 6.11e-08 1.21e-07 1.65e-07 2.91e-07 4.54e-07 6.30e-07 erg/cm2
Error 1.10e-08 1.70e-08 2.83e-08 2.63e-07 6.63e-08 2.75e-07 erg/cm2
Peak flux Cutoff-PL 2.00e-01 2.54e-01 1.82e-01 9.09e-02 6.93e-01 7.27e-01 ph/cm2/s
Error 7.90e-02 5.98e-02 4.64e-02 1.37e-01 1.35e-01 1.97e-01 ph/cm2/s
Fluence Band 6.05e-08 1.20e-07 1.65e-07 2.91e-07 4.54e-07 6.28e-07 erg/cm2
Error 1.45e-08 1.71e-08 2.83e-08 2.63e-07 6.75e-08 2.75e-07 erg/cm2
Peak flux Band 2.00e-01 2.60e-01 1.72e-01 1.65e-01 7.02e-01 7.99e-01 ph/cm2/s
Error 8.37e-02 6.51e-02 4.55e-02 1.08e-01 1.40e-01 1.88e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.524 0.210 - - 1.52e-03 1.85e-04 47.783 57
CPL 1.107 0.690 106.4 5000.0 2.46e-03 2.31e-03 47.312 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.431 0.312 - - 5.78e-03 1.08e-03 44.236 57
CPL 0.697 1.187 84.7 4974.6 1.42e-02 5.38e-02 43.261 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: 2.816000 sec.
T50 in the 50-300 keV band: 1.408000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 32.384 -10.752 21.632
T90 28.736 -9.856 18.880
T50 8.320 -0.576 7.744
Peak 1.000 1.772 2.772
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
75.0827 +14.9650 0.0160 17.1 121.5 0.7569 12.0 TRIG_00181156
------------------------------------------
Foreground time interval of the image:
-10.752 21.632 (delta_t = 32.384 [sec])
Background time interval of the image:
-299.776 -10.752 (delta_t = 289.024 [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 -10.752 sec. to 21.632 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.52361 ( -0.208707 0.211835 )
Norm@50keV : 1.519182E-03 ( -1.856264E-04 1.836644E-04) )
------------------------------------------------------------
Chi-Squared = 47.78332 using 59 PHA bins.
Reduced chi-squared = 0.8383038 for 57 degrees of freedom
Null hypothesis probability = 0.803
Photon flux (15-150 keV) in 32.38 sec: 0.190884 ( -0.022477 0.022503 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.64938e-07 ( -6.2121e-08 6.29435e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -10.752 sec. to 21.632 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.10742 ( -0.772322 0.606979 )
Epeak [keV] : 106.418 ( -106.408 9893.58 )
Norm@50keV : 2.461707E-03 ( -1.108008E-03 3.507115E-03) )
------------------------------------------------------------
Chi-Squared = 47.31231 using 59 PHA bins.
Reduced chi-squared = 0.8448626 for 56 degrees of freedom
Null hypothesis probability = 0.789
Photon flux (15-150 keV) in 32.38 sec: 0.188455 ( -0.02328 0.023118 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.54463e-07 ( -6.74961e-08 6.50514e-08 ) ergs/cm2
Band function
Time interval is from -10.752 sec. to 21.632 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.13496 ( -0.578416 0.424744 )
beta : -6.83798 ( -3.16202 6.90343 )
Epeak [keV] : 110.451 ( -110.351 9889.55 )
Norm@50keV : 2.399222E-03 ( -1.044889E-03 3.537152E-03) )
------------------------------------------------------------
Chi-Squared = 47.28289 using 59 PHA bins.
Reduced chi-squared = 0.8596888 for 55 degrees of freedom
Null hypothesis probability = 0.761
Photon flux (15-150 keV) in 32.38 sec: 0.188447 ( -0.02325 0.023186 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.54139e-07 ( -6.75253e-08 6.75188e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 1.792 sec. to 2.752 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.43090 ( -0.311764 0.312179 )
Norm@50keV : 5.777598E-03 ( -1.089224E-03 1.080223E-03) )
------------------------------------------------------------
Chi-Squared = 44.23584 using 59 PHA bins.
Reduced chi-squared = 0.7760673 for 57 degrees of freedom
Null hypothesis probability = 0.892
Photon flux (15-150 keV) in 0.9600 sec: 0.708702 ( -0.131906 0.132135 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.32812e-08 ( -1.09864e-08 1.11641e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.792 sec. to 2.752 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.696593 ( -1.66823 0.704865 )
Epeak [keV] : 84.6831 ( -33.9877 9915.32 )
Norm@50keV : 1.415001E-02 ( -1.415001E-02 9.352683E-02) )
------------------------------------------------------------
Chi-Squared = 43.26051 using 59 PHA bins.
but latest trial 1.84788 gives Chi-Squared = 5.70622
Reduced chi-squared = 0.7725092 for 56 degrees of freedom
Null hypothesis probability = 0.893
Photon flux (15-150 keV) in 0.9600 sec: 0.693315 ( -0.135291 0.135037 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.01901e-08 ( -1.23747e-08 1.23799e-08 ) ergs/cm2
Band function
Time interval is from 1.792 sec. to 2.752 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.788535 ( -10.7885 4.21147 )
beta : -1.70547 ( -0.764426 0.461261 )
Epeak [keV] : 41.6733 ( -41.5733 543.947 )
Norm@50keV : 0.156527 ( -76.6229 18.7920 )
------------------------------------------------------------
Chi-Squared = 42.15955 using 59 PHA bins.
Reduced chi-squared = 0.7665373 for 55 degrees of freedom
Null hypothesis probability = 0.898
Photon flux (15-150 keV) in 0.9600 sec: 0.701706 ( -0.140333 0.140006 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.01669e-08 ( -1.2303e-08 1.24333e-08 ) ergs/cm2
Plot creation:
Mon Dec 31 12:35:08 EST 2007