batgrbproduct Analysis for Trigger=230115
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 04:39:10 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger230115/SDC
======================================================================
Trigger: 00230115 Segment: 000
BAT Trigger Time: 180344920.128 [s; MET]
Trigger Stop: 180344921.152 [s; MET]
UTC: 2006-09-19T07:48:38.674380 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 276.91131212325 Dec: -51.0275372613452 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.13
Image Trigger?: NO
Rate S/N Ratio: 25.1594912508182 [ if not an image trigger ]
Image S/N Ratio: 9.13
Flight Position: [ source = BAT ]
RA: 276.91131212325 Dec: -51.0275372613452 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 276.898651080415 Dec: -50.998648810817 [deg; J2000]
{ 18h 27m 35.7s , -50d 59' 55.1" }
+/- 1.71570104108331 [arcmin] (estimated 90% radius based on SNR)
+/- 0.855220870358756 [arcmin] (formal 1-sigma fit error)
SNR: 14.0670097159595
RA = 18h 27m 35.7s (276.898651 deg.)
Dec = -50d 59' 55" (-50.998649 deg.)
Angular difference between Flight and Ground position is 1.797992 arcmin
Partial Coding Fraction: 0.2929688 [ including projection effects ]
Duration
T90: 7.3759999871254 +/- 1.7695931635695
Measured from: -0.783999979496002
to: 6.59200000762939 [s; relative to TRIGTIME]
T50: 3.24399998784065 +/- 2.71029446688634
Measured from: -0.0039999783039093
to: 3.24000000953674 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.488000005483627
to: 0.511999994516373 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.01199999451637
to: 9.02799999713898 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.323936 0.365929 0.209650 0.052564
0.036789 0.033385 0.027457 0.021917 [error]
Peak 0.055067 0.105784 0.093996 0.019763
0.012351 0.012041 0.010648 0.007316 [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 1.05e-07 1.56e-07 1.74e-07 3.64e-07 5.46e-07 7.98e-07 erg/cm2
Error 1.75e-08 1.67e-08 2.67e-08 1.15e-07 6.35e-08 1.40e-07 erg/cm2
Peak flux Power-law 6.37e-01 7.21e-01 5.84e-01 7.89e-01 2.23e+00 2.73e+00 ph/cm2/s
Error 1.49e-01 1.08e-01 7.87e-02 2.11e-01 2.99e-01 3.41e-01 ph/cm2/s
Fluence Cutoff-PL 9.14e-08 1.76e-07 1.75e-07 8.74e-08 5.02e-07 5.29e-07 erg/cm2
Error 2.12e-08 2.33e-08 3.18e-08 1.18e-07 7.11e-08 1.38e-07 erg/cm2
Peak flux Cutoff-PL 4.32e-01 7.84e-01 7.02e-01 2.87e-01 2.12e+00 2.21e+00 ph/cm2/s
Error 1.77e-01 1.30e-01 1.10e-01 1.85e-01 3.04e-01 3.51e-01 ph/cm2/s
Fluence Band 9.15e-08 1.76e-07 1.72e-07 1.59e-07 5.08e-07 6.20e-07 erg/cm2
Error 2.13e-08 2.33e-08 3.15e-08 1.40e-07 6.52e-08 1.85e-07 erg/cm2
Peak flux Band 4.31e-01 7.84e-01 7.02e-01 2.86e-01 2.12e+00 2.20e+00 ph/cm2/s
Error 1.77e-01 1.30e-01 1.10e-01 1.55e-01 3.04e-01 6.66e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.849 0.187 - - 5.91e-03 6.82e-04 74.357 57
CPL 0.755 1.013 51.6 21.9 2.31e-02 4.24e-02 69.842 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.303 0.196 - - 1.87e-02 2.34e-03 62.651 57
CPL -0.230 1.089 82.7 30.2 9.15e-02 1.33e-01 54.244 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: 1.472000 sec.
T50 in the 50-300 keV band: 0.640000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 10.040 -1.012 9.028
T90 7.376 -0.784 6.592
T50 3.244 -0.004 3.240
Peak 1.000 -0.488 0.512
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
276.8987 -50.9986 0.0137 32.9 112.6 0.9312 14.1 TRIG_00230115
------------------------------------------
Foreground time interval of the image:
-1.012 9.028 (delta_t = 10.040 [sec])
Background time interval of the image:
-239.128 -1.012 (delta_t = 238.116 [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 -1.012 sec. to 9.028 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.84865 ( -0.184137 0.189036 )
Norm@50keV : 5.912245E-03 ( -6.865179E-04 6.770659E-04) )
------------------------------------------------------------
Chi-Squared = 74.35740 using 59 PHA bins.
Reduced chi-squared = 1.304516 for 57 degrees of freedom
Null hypothesis probability = 6.106E-02
Photon flux (15-150 keV) in 10.04 sec: 0.830573 ( -0.090571 0.090835 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.45794e-07 ( -6.31335e-08 6.38514e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.012 sec. to 9.028 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.755495 ( -1.13071 0.894352 )
Epeak [keV] : 51.6021 ( -10.0505 33.7448 )
Norm@50keV : 2.309163E-02 ( -1.535342E-02 6.942019E-02) )
------------------------------------------------------------
Chi-Squared = 69.84229 using 59 PHA bins.
Reduced chi-squared = 1.247184 for 56 degrees of freedom
Null hypothesis probability = 0.101
Photon flux (15-150 keV) in 10.04 sec: 0.793118 ( -0.096704 0.096041 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.01619e-07 ( -6.91013e-08 7.31484e-08 ) ergs/cm2
Band function
Time interval is from -1.012 sec. to 9.028 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.752805 ( -0.896911 1.01019 )
beta : -9.26272 ( -0.737275 7.35219 )
Epeak [keV] : 51.5967 ( -10.1028 33.7622 )
Norm@50keV : 2.315997E-02 ( -1.337765E-02 5.755966E-02) )
------------------------------------------------------------
Chi-Squared = 69.84232 using 59 PHA bins.
Reduced chi-squared = 1.269860 for 55 degrees of freedom
Null hypothesis probability = 8.580E-02
Photon flux (15-150 keV) in 10.04 sec: 0.793478 ( -0.092747 0.094725 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.07747e-07 ( -6.13846e-08 6.89879e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.488 sec. to 0.512 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30304 ( -0.196825 0.194209 )
Norm@50keV : 1.868767E-02 ( -2.341727E-03 2.339333E-03) )
------------------------------------------------------------
Chi-Squared = 62.65079 using 59 PHA bins.
Reduced chi-squared = 1.099137 for 57 degrees of freedom
Null hypothesis probability = 0.283
Photon flux (15-150 keV) in 1.000 sec: 2.23081 ( -0.29781 0.29972 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.84478e-07 ( -2.3719e-08 2.3875e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.488 sec. to 0.512 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.229533 ( -1.22238 0.956343 )
Epeak [keV] : 82.7153 ( -15.6677 44.6503 )
Norm@50keV : 9.149800E-02 ( -5.647138E-02 0.210444 )
------------------------------------------------------------
Chi-Squared = 54.24387 using 59 PHA bins.
Reduced chi-squared = 0.9686406 for 56 degrees of freedom
Null hypothesis probability = 0.542
Photon flux (15-150 keV) in 1.000 sec: 2.12485 ( -0.30169 0.30534 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78461e-07 ( -2.5302e-08 2.4859e-08 ) ergs/cm2
Band function
Time interval is from -0.488 sec. to 0.512 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.229340 ( -0.956282 3.95791 )
beta : -4.84443 ( -5.15557 14.8436 )
Epeak [keV] : 82.7244 ( -39.7262 44.5481 )
Norm@50keV : 9.146171E-02 ( -5.648940E-02 9.291150E-02) )
------------------------------------------------------------
Chi-Squared = 54.24361 using 59 PHA bins.
Reduced chi-squared = 0.9862474 for 55 degrees of freedom
Null hypothesis probability = 0.503
Photon flux (15-150 keV) in 1.000 sec: 2.12432 ( -0.30114 0.30587 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78159e-07 ( -2.5058e-08 2.5037e-08 ) ergs/cm2
Plot creation:
Wed Jan 2 04:53:25 EST 2008