batgrbproduct Analysis for Trigger=156467
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 9 13:10:58 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger156467/SDC
======================================================================
Trigger: 00156467 Segment: 000
BAT Trigger Time: 149111750.144 [s; MET]
Trigger Stop: 149111751.168 [s; MET]
UTC: 2005-09-22T19:55:50.400700 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 317.390673787551 Dec: -8.77177360830505 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 22.78
Image Trigger?: NO
Rate S/N Ratio: 106.677082824757 [ if not an image trigger ]
Image S/N Ratio: 22.78
Flight Position: [ source = BAT ]
RA: 317.390673787551 Dec: -8.77177360830505 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 317.387780112531 Dec: -8.76280392011565 [deg; J2000]
{ 21h 09m 33.1s , -08d 45' 46.1" }
+/- 0.685982138419762 [arcmin] (estimated 90% radius based on SNR)
+/- 0.204010387706774 [arcmin] (formal 1-sigma fit error)
SNR: 52.1143380902658
RA = 21h 9m 33.1s (317.387780 deg.)
Dec = -8d 45' 46" (-8.762804 deg.)
Angular difference between Flight and Ground position is 0.564874 arcmin
Partial Coding Fraction: 0.53125 [ including projection effects ]
Duration
T90: 4.53999999165535 +/- 0.450457545832013
Measured from: -2.08399999141693
to: 2.45600000023842 [s; relative to TRIGTIME]
T50: 1.41600000858307 +/- 0.0933809188437612
Measured from: -0.403999984264374
to: 1.0120000243187 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0920000076293945
to: 0.907999992370605 [s; relative to TRIGTIME]
Total Fluence
Measured from: -3.31599998474121
to: 3.4839999973774 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.546911 0.887888 0.723425 0.214888
0.020979 0.023214 0.021308 0.015905 [error]
Peak 0.178340 0.336644 0.270883 0.087531
0.009580 0.011591 0.011178 0.007610 [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 3.76e-07 5.81e-07 1.97e-06 1.62e-06 3.11e-06 erg/cm2
Error 1.25e-08 1.44e-08 2.13e-08 1.68e-07 5.35e-08 1.78e-07 erg/cm2
Peak flux Power-law 2.08e+00 2.35e+00 1.90e+00 2.55e+00 7.26e+00 8.88e+00 ph/cm2/s
Error 1.68e-01 1.15e-01 9.00e-02 2.56e-01 3.17e-01 3.73e-01 ph/cm2/s
Fluence Cutoff-PL 1.79e-07 3.81e-07 5.96e-07 1.47e-06 1.61e-06 1.99e-06 erg/cm2
Error 1.61e-08 1.56e-08 2.57e-08 4.20e-07 5.67e-08 0.00e+00 erg/cm2
Peak flux Cutoff-PL 1.90e+00 2.41e+00 1.99e+00 1.75e+00 7.15e+00 8.05e+00 ph/cm2/s
Error 2.07e-01 1.28e-01 1.13e-01 4.82e-01 3.25e-01 5.80e-01 ph/cm2/s
Fluence Band 1.77e-07 3.80e-07 5.95e-07 1.46e-06 1.60e-06 2.11e-06 erg/cm2
Error 1.60e-08 1.55e-08 2.58e-08 3.03e-07 5.66e-08 0.00e+00 erg/cm2
Peak flux Band 1.76e+00 2.52e+00 1.93e+00 2.17e+00 7.06e+00 8.37e+00 ph/cm2/s
Error 1.87e-01 1.54e-01 1.01e-01 3.10e-01 3.27e-01 4.57e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.373 0.059 - - 2.46e-02 7.76e-04 44.875 57
CPL 1.134 0.235 207.7 1325.4 3.14e-02 7.43e-03 41.836 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.308 0.072 - - 6.08e-02 2.51e-03 60.679 57
CPL 0.914 0.296 153.1 138.9 9.26e-02 2.93e-02 54.983 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: 3.904000 sec.
T50 in the 50-300 keV band: 1.344000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 6.800 -3.316 3.484
T90 4.540 -2.084 2.456
T50 1.416 -0.404 1.012
Peak 1.000 -0.092 0.908
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
317.3878 -8.7628 0.0037 34.5 158.8 2.4924 52.1 TRIG_00156467
------------------------------------------
Foreground time interval of the image:
-3.316 3.484 (delta_t = 6.800 [sec])
Background time interval of the image:
-48.139 -3.316 (delta_t = 44.823 [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 -3.316 sec. to 3.484 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37264 ( -5.897784E-02 5.880821E-02) )
Norm@50keV : 2.455953E-02 ( -7.763430E-04 7.761382E-04) )
------------------------------------------------------------
Chi-Squared = 44.87507 using 59 PHA bins.
Reduced chi-squared = 0.7872820 for 57 degrees of freedom
Null hypothesis probability = 0.878
Photon flux (15-150 keV) in 6.800 sec: 2.97286 ( -0.10422 0.10455 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.62297e-06 ( -5.3414e-08 5.35568e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.316 sec. to 3.484 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.13439 ( -0.243487 0.226322 )
Epeak [keV] : 207.706 ( -76.5967 2574.17 )
Norm@50keV : 3.136749E-02 ( -6.216133E-03 8.641645E-03) )
------------------------------------------------------------
Chi-Squared = 41.83596 using 59 PHA bins.
but latest trial 1.35931 gives Chi-Squared = 2.58604
but latest trial 2.502996E-02 gives Chi-Squared = 4.04998
Reduced chi-squared = 0.7470707 for 56 degrees of freedom
Null hypothesis probability = 0.920
Photon flux (15-150 keV) in 6.800 sec: 2.93007 ( -0.05563 0.11152 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.60636e-06 ( -5.68616e-08 5.64604e-08 ) ergs/cm2
Band function
Time interval is from -3.316 sec. to 3.484 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.761211 ( -0.483546 1.80193 )
beta : -1.48771 ( -8.51229 0.113190 )
Epeak [keV] : 89.4184 ( -50.1745 198.049 )
Norm@50keV : 5.159585E-02 ( -2.451593E-02 0.478540 )
------------------------------------------------------------
Chi-Squared = 40.17551 using 59 PHA bins.
Reduced chi-squared = 0.7304638 for 55 degrees of freedom
Null hypothesis probability = 0.933
Photon flux (15-150 keV) in 6.800 sec: 2.89839 ( -0.11831 0.06022 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.60484e-06 ( -5.65556e-08 5.6678e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.092 sec. to 0.908 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.30772 ( -7.201684E-02 7.186317E-02) )
Norm@50keV : 6.076664E-02 ( -2.510410E-03 2.510343E-03) )
------------------------------------------------------------
Chi-Squared = 60.67909 using 59 PHA bins.
Reduced chi-squared = 1.064546 for 57 degrees of freedom
Null hypothesis probability = 0.345
Photon flux (15-150 keV) in 1.000 sec: 7.26003 ( -0.31669 0.31715 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.99359e-07 ( -2.6665e-08 2.6727e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.092 sec. to 0.908 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.913931 ( -0.305984 0.285320 )
Epeak [keV] : 153.116 ( -44.1493 233.630 )
Norm@50keV : 9.264404E-02 ( -2.386134E-02 3.483365E-02) )
------------------------------------------------------------
Chi-Squared = 54.98326 using 59 PHA bins.
Reduced chi-squared = 0.9818440 for 56 degrees of freedom
Null hypothesis probability = 0.513
Photon flux (15-150 keV) in 1.000 sec: 7.15144 ( -0.32443 0.32574 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.90513e-07 ( -2.8208e-08 2.7633e-08 ) ergs/cm2
Band function
Time interval is from -0.092 sec. to 0.908 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -7.557294E-02 ( -0.812231 2.36632 )
beta : -1.49925 ( -0.183563 0.148016 )
Epeak [keV] : 63.3524 ( -30.1517 62.6995 )
Norm@50keV : 0.299279 ( -0.299279 46.6190 )
------------------------------------------------------------
Chi-Squared = 51.47174 using 59 PHA bins.
Reduced chi-squared = 0.9358498 for 55 degrees of freedom
Null hypothesis probability = 0.610
Photon flux (15-150 keV) in 1.000 sec: 7.05945 ( -0.33822 0.31668 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.90073e-07 ( -2.8164e-08 2.7936e-08 ) ergs/cm2
Plot creation:
Wed Jan 9 13:24:16 EST 2008