batgrbproduct Analysis for Trigger=231231
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): Wed Jan 2 06:28:14 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger231231/GCN5_download_cron
======================================================================
Trigger: 00231231 Segment: 000
BAT Trigger Time: 180982123.328 [s; MET]
Trigger Stop: 180982124.352 [s; MET]
UTC: 2006-09-26T16:48:41.859180 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 263.955245477458 Dec: 13.0414075589345 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 11.6
Image Trigger?: NO
Rate S/N Ratio: 17.3205080756888 [ if not an image trigger ]
Image S/N Ratio: 11.6
Flight Position: [ source = BAT ]
RA: 263.955245477458 Dec: 13.0414075589345 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 263.930192551524 Dec: 13.0414302262744 [deg; J2000]
{ 17h 35m 43.2s , +13d 02' 29.1" }
+/- 1.44795315405987 [arcmin] (estimated 90% radius based on SNR)
+/- 0.643196288988597 [arcmin] (formal 1-sigma fit error)
SNR: 17.925409186849
RA = 17h 35m 43.2s (263.930193 deg.)
Dec = 13d 2' 29" (13.041430 deg.)
Angular difference between Flight and Ground position is 1.464405 arcmin
Partial Coding Fraction: 0.9453125 [ including projection effects ]
Duration
T90: 8.02000001072884 +/- 1.21267967741496
Measured from: 0.199999988079071
to: 8.21999999880791 [s; relative to TRIGTIME]
T50: 3.35999998450279 +/- 0.743236166368835
Measured from: 0.988000005483627
to: 4.34799998998642 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.375999987125397
to: 1.3759999871254 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0920000076293945
to: 8.64399999380112 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.243641 0.187884 0.056573 0.024404
0.017278 0.015611 0.012903 0.010796 [error]
Peak 0.058519 0.054035 0.013578 0.005744
0.006149 0.005554 0.004514 0.003734 [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 7.46e-08 7.31e-08 5.01e-08 5.40e-08 2.19e-07 2.51e-07 erg/cm2
Error 9.83e-09 7.82e-09 1.13e-08 2.33e-08 2.55e-08 3.83e-08 erg/cm2
Peak flux Power-law 5.79e-01 3.46e-01 1.32e-01 6.72e-02 1.09e+00 1.13e+00 ph/cm2/s
Error 9.89e-02 4.66e-02 3.44e-02 3.23e-02 1.40e-01 1.44e-01 ph/cm2/s
Fluence Cutoff-PL 7.39e-08 7.31e-08 5.01e-08 5.37e-08 2.19e-07 2.40e-07 erg/cm2
Error 9.86e-09 7.83e-09 1.13e-08 2.31e-08 2.54e-08 5.31e-08 erg/cm2
Peak flux Cutoff-PL 5.63e-01 3.72e-01 1.17e-01 2.08e-02 1.07e+00 1.07e+00 ph/cm2/s
Error 1.05e-01 4.95e-02 4.94e-02 4.75e-02 1.45e-01 1.56e-01 ph/cm2/s
Fluence Band 6.98e-08 7.33e-08 5.23e-08 5.79e-08 2.21e-07 2.69e-07 erg/cm2
Error 9.46e-09 4.87e-09 1.61e-08 3.01e-08 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 5.74e-01 3.63e-01 1.21e-01 4.20e-02 1.08e+00 1.11e+00 ph/cm2/s
Error 1.06e-01 6.69e-02 3.60e-02 3.26e-02 1.48e-01 1.57e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.543 0.229 - - 2.48e-03 4.01e-04 58.456 57
CPL 1.984 0.000 1.0 10.3 5.55e-03 1.41e-03 59.341 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.390 0.272 - - 5.94e-03 1.17e-03 61.727 57
CPL 1.689 1.029 15.5 16.0 1.68e-02 1.27e-01 60.807 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 8.736 -0.092 8.644
T90 8.020 0.200 8.220
T50 3.360 0.988 4.348
Peak 1.000 0.376 1.376
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
263.9302 +13.0414 0.0107 9.1 98.1 0.5359 17.9 TRIG_00231231
------------------------------------------
Foreground time interval of the image:
-0.092 8.644 (delta_t = 8.736 [sec])
Background time interval of the image:
-239.328 -21.328 (delta_t = 218.000 [sec])
-20.328 -0.092 (delta_t = 20.236 [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 -0.092 sec. to 8.644 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.54309 ( -0.221843 0.237149 )
Norm@50keV : 2.481560E-03 ( -4.021954E-04 3.988338E-04) )
------------------------------------------------------------
Chi-Squared = 58.45563 using 59 PHA bins.
Reduced chi-squared = 1.025537 for 57 degrees of freedom
Null hypothesis probability = 0.422
Photon flux (15-150 keV) in 8.736 sec: 0.500651 ( -0.04886 0.048911 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.1939e-07 ( -2.50907e-08 2.58096e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.092 sec. to 8.644 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.98385 ( )
Epeak [keV] : 1.03284 ( -0.275320 20.2779 )
Norm@50keV : 5.549699E-03 ( -1.272009E-03 1.539450E-03) )
------------------------------------------------------------
Chi-Squared = 59.34079 using 59 PHA bins.
but latest trial -0.533776 gives Chi-Squared = 3.01558
Reduced chi-squared = 1.059657 for 56 degrees of freedom
Null hypothesis probability = 0.355
Photon flux (15-150 keV) in 8.736 sec: 0.500437 ( -0.048838 0.04889 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.1936e-07 ( -2.50915e-08 2.58044e-08 ) ergs/cm2
Band function
Time interval is from -0.092 sec. to 8.644 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.59716 ( -8.40284 6.59716 )
beta : -4.03949 ( -0.930474 0.291446 )
Epeak [keV] : 13.9359 ( -15.0987 33.5906 )
Norm@50keV : 1.049770E-02 ( -1.368417E-02 1411.45 )
------------------------------------------------------------
Chi-Squared = 60.44886 using 59 PHA bins.
Reduced chi-squared = 1.099070 for 55 degrees of freedom
Null hypothesis probability = 0.286
Photon flux (15-150 keV) in 8.736 sec: 0.499778 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.21057e-07 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.376 sec. to 1.376 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.39033 ( -0.260507 0.282524 )
Norm@50keV : 5.941036E-03 ( -1.176709E-03 1.159132E-03) )
------------------------------------------------------------
Chi-Squared = 61.72742 using 59 PHA bins.
Reduced chi-squared = 1.082937 for 57 degrees of freedom
Null hypothesis probability = 0.311
Photon flux (15-150 keV) in 1.000 sec: 1.09305 ( -0.139883 0.13991 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.78197e-08 ( -8.866e-09 9.1936e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.376 sec. to 1.376 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.68941 ( -1.75672 0.302254 )
Epeak [keV] : 15.4901 ( -15.4801 16.4595 )
Norm@50keV : 1.677178E-02 ( -1.677177E-02 0.236730 )
------------------------------------------------------------
Chi-Squared = 60.80664 using 59 PHA bins.
Reduced chi-squared = 1.085833 for 56 degrees of freedom
Null hypothesis probability = 0.307
Photon flux (15-150 keV) in 1.000 sec: 1.06943 ( -0.145065 0.14551 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.3213e-08 ( -1.01908e-08 1.17628e-08 ) ergs/cm2
Band function
Time interval is from 0.376 sec. to 1.376 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.53255 ( -10.8627 4.13735 )
beta : -9.32697 ( -0.525860 0.380371 )
Epeak [keV] : 18.8989 ( -20.2549 9.66360 )
Norm@50keV : 2.121601E-02 ( -15.1836 1417.71 )
------------------------------------------------------------
Chi-Squared = 60.83838 using 59 PHA bins.
Reduced chi-squared = 1.106152 for 55 degrees of freedom
Null hypothesis probability = 0.274
Photon flux (15-150 keV) in 1.000 sec: 1.08342 ( -0.150525 0.1447 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.50648e-08 ( -1.07236e-08 1.10111e-08 ) ergs/cm2
Plot creation:
Wed Jan 2 06:48:12 EST 2008