batgrbproduct Analysis for Trigger=303609
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): Tue Feb 19 05:12:25 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger303609/GCN5_download_cron
======================================================================
Trigger: 00303609 Segment: 000
BAT Trigger Time: 225058125.376 [s; MET]
Trigger Stop: 225058129.472 [s; MET]
UTC: 2008-02-18T20:08:42.791800 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 355.921970640896 Dec: 12.174721597336 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.62
Image Trigger?: NO
Rate S/N Ratio: 9.8488578017961 [ if not an image trigger ]
Image S/N Ratio: 6.62
Flight Position: [ source = BAT ]
RA: 355.921970640896 Dec: 12.174721597336 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 355.936878272606 Dec: 12.1545145510239 [deg; J2000]
{ 23h 43m 44.9s , +12d 09' 16.3" }
+/- 2.43279072389081 [arcmin] (estimated 90% radius based on SNR)
+/- 1.09273969649904 [arcmin] (formal 1-sigma fit error)
SNR: 8.54161837515128
RA = 23h 43m 44.9s (355.936878 deg.)
Dec = 12d 9' 16" (12.154515 deg.)
Angular difference between Flight and Ground position is 1.494824 arcmin
Partial Coding Fraction: 0.2109375 [ including projection effects ]
Duration
T90: 22.5279999673367 +/- 5.6594162095639
Measured from: -11.5039999783039
to: 11.0239999890327 [s; relative to TRIGTIME]
T50: 7.58399999141693 +/- 7.17352018969372
Measured from: 1.32800000905991
to: 8.91200000047684 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.21999999880791
to: 2.21999999880791 [s; relative to TRIGTIME]
Total Fluence
Measured from: -12.3519999980927
to: 19.5680000185966 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.452308 0.521992 0.159970 0.061230
0.070685 0.072258 0.065848 0.061317 [error]
Peak 0.049233 0.051941 0.026669 0.007736
0.013652 0.014049 0.012246 0.010949 [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 1.89e-07 2.16e-07 1.77e-07 2.43e-07 6.72e-07 8.32e-07 erg/cm2
Error 4.25e-08 3.97e-08 5.89e-08 1.54e-07 1.40e-07 2.33e-07 erg/cm2
Peak flux Power-law 8.08e-01 4.25e-01 1.39e-01 5.87e-02 1.41e+00 1.43e+00 ph/cm2/s
Error 2.92e-01 1.42e-01 9.31e-02 8.13e-02 4.01e-01 4.11e-01 ph/cm2/s
Fluence Cutoff-PL 1.67e-07 2.64e-07 1.53e-07 2.31e-08 6.04e-07 6.04e-07 erg/cm2
Error 5.03e-08 5.85e-08 7.71e-08 8.42e-08 1.38e-07 1.61e-07 erg/cm2
Peak flux Cutoff-PL 8.08e-01 4.26e-01 1.39e-01 5.83e-02 1.41e+00 1.43e+00 ph/cm2/s
Error 2.92e-01 1.42e-01 9.31e-02 8.08e-02 4.01e-01 4.11e-01 ph/cm2/s
Fluence Band 1.64e-07 2.63e-07 1.51e-07 2.21e-08 6.01e-07 5.91e-07 erg/cm2
Error 2.80e-08 4.65e-08 3.54e-08 1.13e-07 9.27e-08 1.61e-07 erg/cm2
Peak flux Band 8.08e-01 4.26e-01 1.39e-01 5.83e-02 1.41e+00 1.43e+00 ph/cm2/s
Error 2.96e-01 1.42e-01 9.31e-02 8.08e-02 3.02e-01 4.11e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.287 0.336 - - 2.21e-03 5.44e-04 51.202 57
CPL 0.471 1.991 33.1 21.9 2.68e-02 4.48e-01 47.188 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.612 0.718 - - 6.67e-03 3.43e-03 48.463 57
CPL 1.919 0.000 4.3 0.0 1.80e-02 1.28e-02 48.702 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 31.920 -12.352 19.568
T90 22.528 -11.504 11.024
T50 7.584 1.328 8.912
Peak 1.000 1.220 2.220
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
355.9369 +12.1545 0.0225 47.4 -36.1 1.3061 8.5 TRIG_00303609
------------------------------------------
Foreground time interval of the image:
-12.352 19.568 (delta_t = 31.920 [sec])
Background time interval of the image:
-239.376 -169.546 (delta_t = 69.830 [sec])
-168.376 -12.352 (delta_t = 156.024 [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 -12.352 sec. to 19.568 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.28739 ( -0.315280 0.356365 )
Norm@50keV : 2.206811E-03 ( -5.493470E-04 5.381985E-04) )
------------------------------------------------------------
Chi-Squared = 51.20160 using 59 PHA bins.
Reduced chi-squared = 0.8982736 for 57 degrees of freedom
Null hypothesis probability = 0.691
Photon flux (15-150 keV) in 31.92 sec: 0.383136 ( -0.066926 0.066945 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.71929e-07 ( -1.37546e-07 1.42756e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -12.352 sec. to 19.568 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.470835 ( -2.50078 1.48052 )
Epeak [keV] : 33.0629 ( -33.0529 10.7499 )
Norm@50keV : 2.680625E-02 ( -2.680625E-02 0.869476 )
------------------------------------------------------------
Chi-Squared = 47.18832 using 59 PHA bins.
but latest trial 2.06451 gives Chi-Squared = 5.33987
Reduced chi-squared = 0.8426486 for 56 degrees of freedom
Null hypothesis probability = 0.793
Photon flux (15-150 keV) in 31.92 sec: 0.366600 ( -0.068495 0.068395 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.0378e-07 ( -1.29289e-07 1.46538e-07 ) ergs/cm2
Band function
Time interval is from -12.352 sec. to 19.568 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.720078 ( -1.11538 3.40141 )
beta : -9.22806 ( -0.771945 19.2279 )
Epeak [keV] : 32.4292 ( -21.8291 11.5213 )
Norm@50keV : 1.890364E-02 ( -3.227161E-03 1.36729 )
------------------------------------------------------------
Chi-Squared = 47.24236 using 59 PHA bins.
Reduced chi-squared = 0.8589520 for 55 degrees of freedom
Null hypothesis probability = 0.762
Photon flux (15-150 keV) in 31.92 sec: 0.366301 ( -0.063479 0.034637 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.01427e-07 ( -1.02683e-07 8.26409e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 1.216 sec. to 2.224 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.61213 ( -0.608378 0.827482 )
Norm@50keV : 6.669008E-03 ( -3.470335E-03 3.381759E-03) )
------------------------------------------------------------
Chi-Squared = 48.46346 using 59 PHA bins.
Reduced chi-squared = 0.8502361 for 57 degrees of freedom
Null hypothesis probability = 0.782
Photon flux (15-150 keV) in 1.008 sec: 1.40552 ( -0.40138 0.4014 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.94484e-08 ( -2.42077e-08 2.61163e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.216 sec. to 2.224 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.91895 ( )
Epeak [keV] : 4.30712 ( )
Norm@50keV : 1.802440E-02 ( -1.610802E-02 9.486504E-03) )
------------------------------------------------------------
Chi-Squared = 48.70193 using 59 PHA bins.
but latest trial -1.31483 gives Chi-Squared = 1.64799
but latest trial 2.829585E-02 gives Chi-Squared = 4.09032
Reduced chi-squared = 0.8696772 for 56 degrees of freedom
Null hypothesis probability = 0.745
Photon flux (15-150 keV) in 1.008 sec: 1.40501 ( -0.40124 0.40125 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.9324e-08 ( -2.65638e-08 2.62612e-08 ) ergs/cm2
Band function
Time interval is from 1.216 sec. to 2.224 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.71988 ( -3.99855 11.0015 )
beta : -9.30616 ( )
Epeak [keV] : 14.2099 ( )
Norm@50keV : 2.099003E-02 ( )
------------------------------------------------------------
Chi-Squared = 48.95597 using 59 PHA bins.
Reduced chi-squared = 0.8901086 for 55 degrees of freedom
Null hypothesis probability = 0.704
Photon flux (15-150 keV) in 1.008 sec: 1.40501 ( -0.20324 0.40125 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.07e-08 ( -2.01937e-08 2.48405e-08 ) ergs/cm2
Plot creation:
Tue Feb 19 05:44:51 EST 2008