batgrbproduct Analysis for Trigger=323898
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 Sep 5 16:38:18 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger323898/GCN5_download_cron
======================================================================
Trigger: 00323898 Segment: 000
BAT Trigger Time: 242326548.48 [s; MET]
Trigger Stop: 242326550.528 [s; MET]
UTC: 2008-09-05T16:55:45.405420 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 301.72269381416 Dec: -62.5711596742389 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.01
Image Trigger?: NO
Rate S/N Ratio: 15.7797338380595 [ if not an image trigger ]
Image S/N Ratio: 8.01
Flight Position: [ source = BAT ]
RA: 301.72269381416 Dec: -62.5711596742389 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 301.743425041509 Dec: -62.5762533956511 [deg; J2000]
{ 20h 06m 58.4s , -62d 34' 34.5" }
+/- 1.82154516395595 [arcmin] (estimated 90% radius based on SNR)
+/- 0.804694876411343 [arcmin] (formal 1-sigma fit error)
SNR: 12.9140159212157
Angular difference between Flight and Ground position is 0.649355 arcmin
Partial Coding Fraction: 0.3789062 [ including projection effects ]
Duration
T90: 94.136000007391 +/- 10.0016670545597
Measured from: 0.188000112771988
to: 94.324000120163 [s; relative to TRIGTIME]
T50: 75.0640000104904 +/- 6.00963093967201
Measured from: 3.72400009632111
to: 78.7880001068115 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 2.45600000023842
to: 3.45600000023842 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.727999985218048
to: 104.600000023842 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.829819 1.044581 0.720139 0.141027
0.074116 0.071510 0.061476 0.052438 [error]
Peak 0.048523 0.060929 0.060898 0.013835
0.010205 0.010062 0.009169 0.007412 [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 3.03e-07 4.73e-07 5.56e-07 1.26e-06 1.70e-06 2.60e-06 erg/cm2
Error 3.92e-08 3.77e-08 6.00e-08 2.86e-07 1.43e-07 3.36e-07 erg/cm2
Peak flux Power-law 5.26e-01 5.30e-01 3.75e-01 4.23e-01 1.60e+00 1.85e+00 ph/cm2/s
Error 1.53e-01 9.55e-02 7.29e-02 1.68e-01 2.71e-01 2.99e-01 ph/cm2/s
Fluence Cutoff-PL 2.86e-07 4.91e-07 5.68e-07 7.49e-07 1.66e-06 2.08e-06 erg/cm2
Error 4.65e-08 4.64e-08 6.43e-08 4.91e-07 1.54e-07 5.74e-07 erg/cm2
Peak flux Cutoff-PL 4.36e-01 5.53e-01 4.10e-01 2.31e-01 1.54e+00 1.63e+00 ph/cm2/s
Error 1.95e-01 1.07e-01 9.20e-02 2.30e-01 2.85e-01 3.89e-01 ph/cm2/s
Fluence Band 2.83e-07 4.90e-07 5.67e-07 7.49e-07 1.66e-06 2.14e-06 erg/cm2
Error 4.61e-08 4.61e-08 6.48e-08 5.46e-07 1.55e-07 5.77e-07 erg/cm2
Peak flux Band 4.36e-01 5.53e-01 4.10e-01 2.32e-01 1.54e+00 1.63e+00 ph/cm2/s
Error 1.96e-01 1.08e-01 9.20e-02 2.28e-01 2.86e-01 3.89e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.769 0.138 - - 1.77e-03 1.44e-04 52.271 57
CPL 1.339 0.531 76.0 4971.9 2.91e-03 1.89e-03 50.952 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.498 0.277 - - 1.28e-02 2.07e-03 51.464 57
CPL 0.741 1.202 93.2 5000.0 2.84e-02 5.46e-02 50.180 56
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: 89.472000 sec.
T50 in the 50-300 keV band: 75.392000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 105.328 -0.728 104.600
T90 94.136 0.188 94.324
T50 75.064 3.724 78.788
Peak 1.000 2.456 3.456
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
301.7434 -62.5763 0.0148 44.8 177.7 1.2263 12.9 TRIG_00323898
------------------------------------------
Foreground time interval of the image:
-0.728 8.670 (delta_t = 9.398 [sec])
9.520 24.521 (delta_t = 15.001 [sec])
Background time interval of the image:
-119.480 -56.711 (delta_t = 62.769 [sec])
-55.480 -0.728 (delta_t = 54.752 [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
Multiple GTIs in the spectrum
tstart tstop
-0.728000 8.670000
9.520000 104.600000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.76887 ( -0.136995 0.139544 )
Norm@50keV : 1.766050E-03 ( -1.447223E-04 1.436681E-04) )
------------------------------------------------------------
Chi-Squared = 52.27142 using 59 PHA bins.
Reduced chi-squared = 0.9170425 for 57 degrees of freedom
Null hypothesis probability = 0.653
Photon flux (15-150 keV) in 104.5 sec: 0.240481 ( -0.019508 0.019564 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.70117e-06 ( -1.42496e-07 1.43416e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-0.728000 8.670000
9.520000 104.600000
Parameters : value lower 90% higher 90%
Photon index: 1.33901 ( -0.532974 0.528949 )
Epeak [keV] : 76.0230 ( -19.7989 9923.98 )
Norm@50keV : 2.914445E-03 ( -1.314546E-03 2.465524E-03) )
------------------------------------------------------------
Chi-Squared = 50.95168 using 59 PHA bins.
but latest trial 40.9604 gives Chi-Squared = 8.69580
but latest trial 1.628611E-03 gives Chi-Squared = 6.74183
Reduced chi-squared = 0.9098514 for 56 degrees of freedom
Null hypothesis probability = 0.666
Photon flux (15-150 keV) in 104.5 sec: 0.236105 ( -0.020473 0.020497 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.66153e-06 ( -1.5465e-07 1.54326e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-0.728000 8.670000
9.520000 104.600000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.40469 ( -0.461554 0.593689 )
beta : -8.05678 ( -1.94322 6.29384 )
Epeak [keV] : 80.7973 ( -25.2547 9919.20 )
Norm@50keV : 2.708629E-03 ( -1.043046E-03 2.646269E-03) )
------------------------------------------------------------
Chi-Squared = 50.90908 using 59 PHA bins.
Reduced chi-squared = 0.9256196 for 55 degrees of freedom
Null hypothesis probability = 0.632
Photon flux (15-150 keV) in 104.5 sec: 0.236114 ( -0.020488 0.020511 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.6597e-06 ( -1.54785e-07 1.54796e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 2.456 sec. to 3.456 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.49784 ( -0.273968 0.280015 )
Norm@50keV : 1.280750E-02 ( -2.077320E-03 2.072429E-03) )
------------------------------------------------------------
Chi-Squared = 51.46423 using 59 PHA bins.
Reduced chi-squared = 0.9028811 for 57 degrees of freedom
Null hypothesis probability = 0.682
Photon flux (15-150 keV) in 1.000 sec: 1.59795 ( -0.27011 0.2718 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.21521e-07 ( -2.0928e-08 2.113e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.456 sec. to 3.456 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.741060 ( -1.44746 0.956565 )
Epeak [keV] : 93.1672 ( -93.1572 9906.83 )
Norm@50keV : 2.838820E-02 ( -1.705779E-02 9.206896E-02) )
------------------------------------------------------------
Chi-Squared = 50.18038 using 59 PHA bins.
Reduced chi-squared = 0.8960782 for 56 degrees of freedom
Null hypothesis probability = 0.694
Photon flux (15-150 keV) in 1.000 sec: 1.53733 ( -0.28545 0.2854 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.184e-07 ( -2.17205e-08 2.1803e-08 ) ergs/cm2
Band function
Time interval is from 2.456 sec. to 3.456 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.745945 ( -0.951894 1.45234 )
beta : -8.93322 ( -1.06678 7.63286 )
Epeak [keV] : 93.4415 ( -31.8367 9906.56 )
Norm@50keV : 2.823352E-02 ( -1.690520E-02 9.230071E-02) )
------------------------------------------------------------
Chi-Squared = 50.18051 using 59 PHA bins.
Reduced chi-squared = 0.9123729 for 55 degrees of freedom
Null hypothesis probability = 0.659
Photon flux (15-150 keV) in 1.000 sec: 1.53790 ( -0.28579 0.28599 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.18351e-07 ( -2.17269e-08 2.1751e-08 ) ergs/cm2
Plot creation:
Fri Sep 5 16:46:43 EDT 2008