batgrbproduct Analysis for Trigger=315819
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): Fri Jul 4 01:42:42 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger315819/GCN5_download_cron
======================================================================
Trigger: 00315819 Segment: 000
BAT Trigger Time: 236804416.512 [s; MET]
Trigger Stop: 236804417.536 [s; MET]
UTC: 2008-07-03T19:00:13.598700 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 101.866687854747 Dec: -63.2222518285121 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.3
Image Trigger?: NO
Rate S/N Ratio: 11.7898261225516 [ if not an image trigger ]
Image S/N Ratio: 7.3
Flight Position: [ source = BAT ]
RA: 101.866687854747 Dec: -63.2222518285121 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 101.827723474158 Dec: -63.2157814105234 [deg; J2000]
{ 06h 47m 18.7s , -63d 12' 56.8" }
+/- 2.17663779084835 [arcmin] (estimated 90% radius based on SNR)
+/- 0.894253676046761 [arcmin] (formal 1-sigma fit error)
SNR: 10.0130576244724
Angular difference between Flight and Ground position is 1.122659 arcmin
Partial Coding Fraction: 0.5390625 [ including projection effects ]
Duration
T90: 3.44400000572205 +/- 0.759360248491152
Measured from: -1.47200000286102
to: 1.97200000286102 [s; relative to TRIGTIME]
T50: 1.49200001358986 +/- 0.469863811482504
Measured from: -0.73199999332428
to: 0.760000020265579 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.0439999997615814
to: 1.04399999976158 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.7039999961853
to: 2.13199999928474 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.073589 0.131371 0.088125 0.005555
0.014754 0.014977 0.013568 0.011231 [error]
Peak 0.025048 0.048029 0.034787 0.004429
0.007700 0.007929 0.007138 0.005649 [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 2.76e-08 4.99e-08 6.91e-08 1.99e-07 1.99e-07 3.39e-07 erg/cm2
Error 6.18e-09 7.26e-09 1.25e-08 7.35e-08 3.08e-08 8.45e-08 erg/cm2
Peak flux Power-law 2.93e-01 3.13e-01 2.38e-01 2.93e-01 9.55e-01 1.14e+00 ph/cm2/s
Error 1.01e-01 6.93e-02 5.54e-02 1.37e-01 1.97e-01 2.29e-01 ph/cm2/s
Fluence Cutoff-PL 2.40e-08 5.74e-08 7.15e-08 4.39e-08 1.82e-07 1.99e-07 erg/cm2
Error 6.98e-09 1.01e-08 1.54e-08 6.94e-08 3.43e-08 7.67e-08 erg/cm2
Peak flux Cutoff-PL 2.63e-01 3.42e-01 2.52e-01 1.30e-01 9.38e-01 9.87e-01 ph/cm2/s
Error 1.11e-01 8.75e-02 6.43e-02 2.03e-01 1.98e-01 2.62e-01 ph/cm2/s
Fluence Band 2.16e-08 6.12e-08 6.62e-08 1.17e-07 1.88e-07 2.56e-07 erg/cm2
Error 8.37e-09 1.01e-08 1.16e-08 7.53e-08 3.04e-08 1.04e-07 erg/cm2
Peak flux Band 2.58e-01 3.60e-01 2.39e-01 2.26e-01 9.53e-01 1.09e+00 ph/cm2/s
Error 1.96e-01 8.93e-02 5.57e-02 1.57e-01 1.88e-01 2.71e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.531 0.224 - - 5.49e-03 7.90e-04 74.499 57
CPL 0.359 1.168 65.2 57.1 2.33e-02 5.88e-02 70.295 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.399 0.320 - - 7.85e-03 1.57e-03 82.482 57
CPL 0.651 1.196 87.3 4974.9 1.94e-02 7.41e-02 81.363 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 3.836 -1.704 2.132
T90 3.444 -1.472 1.972
T50 1.492 -0.732 0.760
Peak 1.000 0.044 1.044
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
101.8277 -63.2158 0.0192 39.0 1.6 0.2835 10.0 TRIG_00315819
------------------------------------------
Foreground time interval of the image:
-1.704 2.132 (delta_t = 3.836 [sec])
Background time interval of the image:
-227.811 -188.012 (delta_t = 39.799 [sec])
-186.512 -1.704 (delta_t = 184.808 [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 -1.704 sec. to 2.132 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.53107 ( -0.222687 0.224674 )
Norm@50keV : 5.488620E-03 ( -7.926412E-04 7.868339E-04) )
------------------------------------------------------------
Chi-Squared = 74.49927 using 59 PHA bins.
Reduced chi-squared = 1.307005 for 57 degrees of freedom
Null hypothesis probability = 5.972E-02
Photon flux (15-150 keV) in 3.836 sec: 0.691076 ( -0.098647 0.098857 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.98799e-07 ( -3.06063e-08 3.09143e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.704 sec. to 2.132 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.359014 ( -1.34062 0.994873 )
Epeak [keV] : 65.2062 ( -16.0005 98.1641 )
Norm@50keV : 2.331987E-02 ( -1.665572E-02 0.100874 )
------------------------------------------------------------
Chi-Squared = 70.29462 using 59 PHA bins.
but latest trial 7.006111E-03 gives Chi-Squared = 13.9559
Reduced chi-squared = 1.255261 for 56 degrees of freedom
Null hypothesis probability = 9.473E-02
Photon flux (15-150 keV) in 3.836 sec: 0.667516 ( -0.100572 0.100834 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.81565e-07 ( -3.38696e-08 3.46368e-08 ) ergs/cm2
Band function
Time interval is from -1.704 sec. to 2.132 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.466080 ( -1.32518 4.53392 )
beta : -2.00068 ( -7.99932 0.445773 )
Epeak [keV] : 47.1092 ( -5.53888 32.8583 )
Norm@50keV : 8.634733E-02 ( -52.2547 8.44996 )
------------------------------------------------------------
Chi-Squared = 68.14536 using 59 PHA bins.
Reduced chi-squared = 1.239007 for 55 degrees of freedom
Null hypothesis probability = 0.110
Photon flux (15-150 keV) in 3.836 sec: 0.673170 ( -0.092412 0.100582 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.88049e-07 ( -3.12427e-08 2.95207e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.044 sec. to 1.044 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.39908 ( -0.323623 0.317278 )
Norm@50keV : 7.847118E-03 ( -1.567931E-03 1.565401E-03) )
------------------------------------------------------------
Chi-Squared = 82.48183 using 59 PHA bins.
Reduced chi-squared = 1.447050 for 57 degrees of freedom
Null hypothesis probability = 1.529E-02
Photon flux (15-150 keV) in 1.000 sec: 0.955434 ( -0.196214 0.197066 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.58233e-08 ( -1.61873e-08 1.64092e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.044 sec. to 1.044 sec.
Parameters : value lower 90% higher 90%
Photon index: 0.651324 ( -1.65060 0.741979 )
Epeak [keV] : 87.2874 ( -37.1762 9912.71 )
Norm@50keV : 1.940710E-02 ( -1.940710E-02 0.128751 )
------------------------------------------------------------
Chi-Squared = 81.36269 using 59 PHA bins.
but latest trial 1.90988 gives Chi-Squared = 7.82575
but latest trial 40.5430 gives Chi-Squared = 7.78237
Reduced chi-squared = 1.452905 for 56 degrees of freedom
Null hypothesis probability = 1.505E-02
Photon flux (15-150 keV) in 1.000 sec: 0.937810 ( -0.19715 0.19851 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.16933e-08 ( -1.79163e-08 1.79734e-08 ) ergs/cm2
Band function
Time interval is from 0.044 sec. to 1.044 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.431039 ( -6.33934 0.219792 )
beta : -1.70480 ( -0.617736 0.662824 )
Epeak [keV] : 46.7902 ( -5.21762 15.4890 )
Norm@50keV : 0.111983 ( -163.129 657.149 )
------------------------------------------------------------
Chi-Squared = 79.59779 using 59 PHA bins.
Reduced chi-squared = 1.447233 for 55 degrees of freedom
Null hypothesis probability = 1.670E-02
Photon flux (15-150 keV) in 1.000 sec: 0.952560 ( -0.187721 0.18902 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.62938e-08 ( -1.47318e-08 1.63275e-08 ) ergs/cm2
Plot creation:
Fri Jul 4 02:25:44 EDT 2008