batgrbproduct Analysis for Trigger=334877
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 v2.42
Process Start Time (local time): Wed Nov 19 08:35:52 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger334877/GCN5_download_cron
======================================================================
Trigger: 00334877 Segment: 000
BAT Trigger Time: 248713000 [s; MET]
Trigger Stop: 248713064 [s; MET]
UTC: 2008-11-18T14:56:36.734580 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 82.5899853305401 Dec: -43.3021771582674 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 15.02
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 15.02
Flight Position: [ source = BAT ]
RA: 82.5899853305401 Dec: -43.3021771582674 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 82.5718403671956 Dec: -43.3043786084092 [deg; J2000]
{ 05h 30m 17.2s , -43d 18' 15.8" }
+/- 1.56772326296886 [arcmin] (estimated 90% radius based on SNR)
+/- 0.75995896878235 [arcmin] (formal 1-sigma fit error)
SNR: 16.0015513795652
Angular difference between Flight and Ground position is 0.803217 arcmin
Partial Coding Fraction: 0.6171875 [ including projection effects ]
Duration
T90: 66.5119999647141 +/- 27.7741796632779
Measured from: 24.808000087738
to: 91.3200000524521 [s; relative to TRIGTIME]
T50: 27.567999958992 +/- 4.98286986693735
Measured from: 36.9040001034737
to: 64.4720000624657 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 46.972000002861
to: 47.972000002861 [s; relative to TRIGTIME]
Total Fluence
Measured from: 19.608000010252
to: 118.583999991417 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.847072 0.857969 0.455450 0.014311
0.061390 0.061716 0.055067 0.048984 [error]
Peak 0.024359 0.026352 0.013060 0.008281
0.006650 0.006737 0.006007 0.005411 [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 2.97e-07 3.79e-07 3.53e-07 5.78e-07 1.22e-06 1.61e-06 erg/cm2
Error 3.53e-08 3.14e-08 5.22e-08 1.69e-07 1.19e-07 2.27e-07 erg/cm2
Peak flux Power-law 2.34e-01 2.04e-01 1.22e-01 1.09e-01 6.06e-01 6.68e-01 ph/cm2/s
Error 1.01e-01 5.68e-02 4.90e-02 8.90e-02 1.68e-01 1.86e-01 ph/cm2/s
Fluence Cutoff-PL 2.82e-07 4.01e-07 3.46e-07 2.47e-07 1.17e-06 1.28e-06 erg/cm2
Error 3.99e-08 4.17e-08 5.82e-08 2.87e-07 1.35e-07 3.15e-07 erg/cm2
Peak flux Cutoff-PL 2.25e-01 2.09e-01 1.24e-01 8.07e-02 6.00e-01 6.40e-01 ph/cm2/s
Error 1.13e-01 6.81e-02 5.33e-02 1.05e-01 1.73e-01 2.10e-01 ph/cm2/s
Fluence Band 2.79e-07 4.00e-07 3.45e-07 2.46e-07 1.16e-06 1.28e-06 erg/cm2
Error 3.95e-08 4.15e-08 5.81e-08 2.86e-07 1.35e-07 3.30e-07 erg/cm2
Peak flux Band 2.25e-01 2.09e-01 1.24e-01 8.07e-02 6.00e-01 6.39e-01 ph/cm2/s
Error 1.69e-01 6.81e-02 5.34e-02 1.03e-01 1.74e-01 2.10e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.101 0.163 - - 1.33e-03 1.42e-04 55.526 57
CPL 1.569 0.619 34.3 24.9 2.67e-03 3.36e-03 53.533 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.745 0.519 - - 4.49e-03 1.40e-03 50.788 57
CPL 1.246 1.723 72.3 0.0 8.20e-03 6.99e-02 50.783 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: 51.840000 sec.
T50 in the 50-300 keV band: 14.912000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 98.976 19.608 118.584
T90 66.512 24.808 91.320
T50 27.568 36.904 64.472
Peak 1.000 46.972 47.972
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
82.5718 -43.3044 0.0120 38.6 -170.2 1.8757 16.0 TRIG_00334877
------------------------------------------
Foreground time interval of the image:
19.608 73.601 (delta_t = 53.993 [sec])
Background time interval of the image:
-68.799 -56.296 (delta_t = 12.503 [sec])
-55.000 11.150 (delta_t = 66.150 [sec])
12.000 19.608 (delta_t = 7.608 [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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 19.608 sec. to 118.584 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.10110 ( -0.158605 0.166560 )
Norm@50keV : 1.330301E-03 ( -1.431013E-04 1.403283E-04) )
------------------------------------------------------------
Chi-Squared = 55.52605 using 59 PHA bins.
Reduced chi-squared = 0.9741412 for 57 degrees of freedom
Null hypothesis probability = 0.531
Photon flux (15-150 keV) in 98.98 sec: 0.209405 ( -0.017381 0.017394 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22352e-06 ( -1.17945e-07 1.19825e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 19.608 sec. to 118.584 sec.
Photon index: 1.56949 ( -0.706375 0.531455 )
Epeak [keV] : 34.3075 ( -33.1464 16.7109 )
Norm@50keV : 2.668599E-03 ( -2.668599E-03 4.049866E-03) )
------------------------------------------------------------
Chi-Squared = 53.53341 using 59 PHA bins.
but latest trial 2.10094 gives Chi-Squared = 1.99950
but latest trial 1.16108 gives Chi-Squared = 6.29228
but latest trial 65.8975 gives Chi-Squared = 3.06023
Reduced chi-squared = 0.9559537 for 56 degrees of freedom
Null hypothesis probability = 0.569
Photon flux (15-150 keV) in 98.98 sec: 0.204638 ( -0.018243 0.018258 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.16622e-06 ( -1.32445e-07 1.37058e-07 ) ergs/cm2
Band function
Time interval is from 19.608 sec. to 118.584 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.64514 ( -8.35486 0.632632 )
beta : -8.85147 ( -1.14853 6.83388 )
Epeak [keV] : 32.8359 ( -16.5899 19.7428 )
Norm@50keV : 2.426478E-03 ( -1.041919E-03 4.319345E-03) )
------------------------------------------------------------
Chi-Squared = 53.55451 using 59 PHA bins.
Reduced chi-squared = 0.9737184 for 55 degrees of freedom
Null hypothesis probability = 0.530
Photon flux (15-150 keV) in 98.98 sec: 0.204653 ( -0.018264 0.018253 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.16456e-06 ( -1.32505e-07 1.36899e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 46.968 sec. to 47.976 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.74495 ( -0.491862 0.546707 )
Norm@50keV : 4.488541E-03 ( -1.441368E-03 1.361339E-03) )
------------------------------------------------------------
Chi-Squared = 50.78765 using 59 PHA bins.
Reduced chi-squared = 0.8910114 for 57 degrees of freedom
Null hypothesis probability = 0.706
Photon flux (15-150 keV) in 1.008 sec: 0.605801 ( -0.168183 0.168504 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.1759e-08 ( -1.32318e-08 1.36878e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 46.968 sec. to 47.976 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.24552 ( -2.46260 0.982709 )
Epeak [keV] : 72.2983 ( )
Norm@50keV : 8.201069E-03 ( -2.151692E-03 0.137745 )
------------------------------------------------------------
Chi-Squared = 50.78297 using 59 PHA bins.
but latest trial 2.22793 gives Chi-Squared = 0.242844
but latest trial 2.817540E-03 gives Chi-Squared = 0.206791
Reduced chi-squared = 0.9068388 for 56 degrees of freedom
Null hypothesis probability = 0.672
Photon flux (15-150 keV) in 1.008 sec: 0.600170 ( -0.174857 0.171412 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.10467e-08 ( -1.39929e-08 1.36146e-08 ) ergs/cm2
Band function
Time interval is from 46.968 sec. to 47.976 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.27439 ( -8.72561 3.56442 )
beta : -2.35126 ( -7.64874 12.2084 )
Epeak [keV] : 74.4017 ( -74.3017 9925.60 )
Norm@50keV : 7.899481E-03 ( -7.899481E-03 13907.6 )
------------------------------------------------------------
Chi-Squared = 50.77193 using 59 PHA bins.
Reduced chi-squared = 0.9231261 for 55 degrees of freedom
Null hypothesis probability = 0.637
Photon flux (15-150 keV) in 1.008 sec: 0.600189 ( -0.175129 0.172349 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.10368e-08 ( -1.3992e-08 1.42472e-08 ) ergs/cm2
Plot creation:
Wed Nov 19 09:25:01 EST 2008