batgrbproduct Analysis for Trigger=315080
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 Jun 23 23:44:47 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger315080/GCN5_download_cron
======================================================================
Trigger: 00315080 Segment: 000
BAT Trigger Time: 235909531.328 [s; MET]
Trigger Stop: 235909531.84 [s; MET]
UTC: 2008-06-23T10:25:28.440240 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 237.659837169095 Dec: -62.0380947683357 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.53
Image Trigger?: NO
Rate S/N Ratio: 12.0415945787923 [ if not an image trigger ]
Image S/N Ratio: 7.53
Flight Position: [ source = BAT ]
RA: 237.659837169095 Dec: -62.0380947683357 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 237.667153566644 Dec: -62.0436500827693 [deg; J2000]
{ 15h 50m 40.1s , -62d 02' 37.1" }
+/- 1.37666718620988 [arcmin] (estimated 90% radius based on SNR)
+/- 0.660521738430828 [arcmin] (formal 1-sigma fit error)
SNR: 19.2659883385746
Angular difference between Flight and Ground position is 0.391741 arcmin
Partial Coding Fraction: 0.3320312 [ including projection effects ]
Duration
T90: 15.1520000100136 +/- 5.16703280752161
Measured from: -0.168000012636185
to: 14.9839999973774 [s; relative to TRIGTIME]
T50: 6.36800000071526 +/- 0.990724984794847
Measured from: 1.30799999833107
to: 7.67599999904633 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 7.22799998521805
to: 8.22799998521805 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.672000020742416
to: 15.9880000054836 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.385269 0.550713 0.482487 0.128994
0.040439 0.041446 0.038582 0.037779 [error]
Peak 0.057348 0.097033 0.074921 0.023680
0.010393 0.011507 0.010693 0.009239 [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 1.16e-07 2.33e-07 3.66e-07 1.27e-06 1.02e-06 1.98e-06 erg/cm2
Error 1.76e-08 2.08e-08 3.81e-08 2.98e-07 9.35e-08 3.23e-07 erg/cm2
Peak flux Power-law 5.75e-01 6.46e-01 5.19e-01 6.94e-01 2.00e+00 2.43e+00 ph/cm2/s
Error 1.34e-01 9.50e-02 8.44e-02 2.29e-01 2.71e-01 3.43e-01 ph/cm2/s
Fluence Cutoff-PL 1.16e-07 2.35e-07 3.68e-07 1.12e-06 1.01e-06 1.60e-06 erg/cm2
Error 2.13e-08 2.24e-08 3.66e-08 5.44e-07 1.01e-07 0.00e+00 erg/cm2
Peak flux Cutoff-PL 4.77e-01 7.12e-01 5.62e-01 2.50e-01 1.92e+00 2.00e+00 ph/cm2/s
Error 1.62e-01 1.21e-01 1.01e-01 2.98e-01 2.83e-01 4.04e-01 ph/cm2/s
Fluence Band 1.11e-07 2.35e-07 3.70e-07 1.05e-06 1.01e-06 1.66e-06 erg/cm2
Error 2.08e-08 2.31e-08 4.17e-08 5.42e-07 1.01e-07 5.57e-07 erg/cm2
Peak flux Band 4.41e-01 7.43e-01 5.39e-01 4.11e-01 1.91e+00 2.13e+00 ph/cm2/s
Error 2.12e-01 1.25e-01 9.88e-02 2.96e-01 2.72e-01 4.13e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.348 0.149 - - 6.26e-03 5.09e-04 62.727 57
CPL 1.178 0.443 255.3 5000.0 7.52e-03 4.01e-03 62.588 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.315 0.222 - - 1.67e-02 2.26e-03 41.969 57
CPL 0.265 1.206 82.6 372.6 5.65e-02 1.29e-01 38.964 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: 8.320000 sec.
T50 in the 50-300 keV band: 5.184000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 16.660 -0.672 15.988
T90 15.152 -0.168 14.984
T50 6.368 1.308 7.676
Peak 1.000 7.228 8.228
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
237.6672 -62.0437 0.0100 31.3 107.4 1.6138 19.3 TRIG_00315080
------------------------------------------
Foreground time interval of the image:
-0.672 15.988 (delta_t = 16.660 [sec])
Background time interval of the image:
-239.328 -0.672 (delta_t = 238.656 [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 -0.672 sec. to 15.988 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.34847 ( -0.149288 0.149583 )
Norm@50keV : 6.263820E-03 ( -5.098237E-04 5.089114E-04) )
------------------------------------------------------------
Chi-Squared = 62.72717 using 59 PHA bins.
Reduced chi-squared = 1.100477 for 57 degrees of freedom
Null hypothesis probability = 0.280
Photon flux (15-150 keV) in 16.66 sec: 0.754373 ( -0.062692 0.062863 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.01965e-06 ( -9.3211e-08 9.38125e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.672 sec. to 15.988 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.17811 ( -0.572236 0.313608 )
Epeak [keV] : 255.300 ( -255.290 9744.70 )
Norm@50keV : 7.522552E-03 ( -1.734185E-03 6.276183E-03) )
------------------------------------------------------------
Chi-Squared = 62.58811 using 59 PHA bins.
Reduced chi-squared = 1.117645 for 56 degrees of freedom
Null hypothesis probability = 0.254
Photon flux (15-150 keV) in 16.66 sec: 0.754087 ( -0.06267 0.062839 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.01289e-06 ( -1.0382e-07 9.83523e-08 ) ergs/cm2
Band function
Time interval is from -0.672 sec. to 15.988 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.08831 ( -8.91169 6.08750 )
beta : -1.34843 ( -0.149481 0.149301 )
Epeak [keV] : 38.8031 ( -38.7031 9961.20 )
Norm@50keV : 1.202623E-02 ( -1.202623E-02 1.33021 )
------------------------------------------------------------
Chi-Squared = 62.72717 using 59 PHA bins.
Reduced chi-squared = 1.140494 for 55 degrees of freedom
Null hypothesis probability = 0.221
Photon flux (15-150 keV) in 16.66 sec: 0.748842 ( -0.066742 0.06598 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.00989e-06 ( -1.01286e-07 1.001e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 7.228 sec. to 8.228 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.31500 ( -0.221931 0.222206 )
Norm@50keV : 1.667529E-02 ( -2.259921E-03 2.254769E-03) )
------------------------------------------------------------
Chi-Squared = 41.96891 using 59 PHA bins.
Reduced chi-squared = 0.7362967 for 57 degrees of freedom
Null hypothesis probability = 0.932
Photon flux (15-150 keV) in 1.000 sec: 1.99501 ( -0.27118 0.27154 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.64229e-07 ( -2.4752e-08 2.5028e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.228 sec. to 8.228 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.264742 ( -1.38336 1.02933 )
Epeak [keV] : 82.6249 ( -23.2949 721.978 )
Norm@50keV : 5.650364E-02 ( -3.895346E-02 0.218062 )
------------------------------------------------------------
Chi-Squared = 38.96363 using 59 PHA bins.
but latest trial 1.752166E-02 gives Chi-Squared = 3.29826
Reduced chi-squared = 0.6957792 for 56 degrees of freedom
Null hypothesis probability = 0.960
Photon flux (15-150 keV) in 1.000 sec: 1.92037 ( -0.2843 0.28269 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.51911e-07 ( -2.7689e-08 2.8265e-08 ) ergs/cm2
Band function
Time interval is from 7.228 sec. to 8.228 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.289386 ( -1.43877 2.94284 )
beta : -1.94639 ( -8.05361 0.635643 )
Epeak [keV] : 64.8033 ( -35.0606 174.671 )
Norm@50keV : 0.118850 ( -0.118850 94.8670 )
------------------------------------------------------------
Chi-Squared = 38.18179 using 59 PHA bins.
Reduced chi-squared = 0.6942143 for 55 degrees of freedom
Null hypothesis probability = 0.959
Photon flux (15-150 keV) in 1.000 sec: 1.91121 ( -0.279 0.26446 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.51762e-07 ( -2.7638e-08 2.8303e-08 ) ergs/cm2
Plot creation:
Tue Jun 24 00:16:48 EDT 2008