batgrbproduct Analysis for Trigger=147072
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): Mon Jan 7 17:30:38 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger147072/GCN5_download_cron
======================================================================
Trigger: 00147072 Segment: 000
BAT Trigger Time: 143660619.824 [s; MET]
Trigger Stop: 143660620.176 [s; MET]
UTC: 2005-07-21T17:43:40.190620 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 16 ms to TRIGTIME + 320 ms
BAT
RA: 272.156537811539 Dec: -20.3971971414983 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 34667
Image Trigger?: NO
Rate S/N Ratio: 123.664869708418 [ if not an image trigger ]
Image S/N Ratio: 34667
Flight Position: [ source = BAT ]
RA: 272.156537811539 Dec: -20.3971971414983 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 272.162006276835 Dec: -20.3986679422596 [deg; J2000]
{ 18h 08m 38.9s , -20d 23' 55.2" }
+/- 1.25076757323967 [arcmin] (estimated 90% radius based on SNR)
+/- 0.345469756007451 [arcmin] (formal 1-sigma fit error)
SNR: 22.0950325925141
RA = 18h 8m 38.9s (272.162006 deg.)
Dec = -20d 23' 55" (-20.398668 deg.)
Angular difference between Flight and Ground position is 0.319945 arcmin
Partial Coding Fraction: 0.734375 [ including projection effects ]
Duration
T90: 0.272000014781952 +/- 0.173666358932228
Measured from: 0.0559999942779541
to: 0.328000009059906 [s; relative to TRIGTIME]
T50: 0.0160000026226044 +/- 0.00400000810623169
Measured from: 0.252000004053116
to: 0.26800000667572 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.291999995708466
to: 0.708000004291534 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0.0480000078678131
to: 0.363999992609024 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.101570 0.074690 0.021185 0.002633
0.005539 0.004858 0.003301 0.002388 [error]
Peak 0.100844 0.075130 0.021410 0.002241
0.005552 0.004872 0.003305 0.002406 [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 3.25e-08 3.03e-08 1.97e-08 1.97e-08 9.06e-08 1.04e-07 erg/cm2
Error 3.52e-09 2.44e-09 3.07e-09 5.88e-09 7.54e-09 0.00e+00 erg/cm2
Peak flux Power-law 3.34e+00 1.75e+00 5.70e-01 2.39e-01 5.80e+00 5.91e+00 ph/cm2/s
Error 3.70e-01 1.38e-01 8.56e-02 6.64e-02 4.69e-01 4.69e-01 ph/cm2/s
Fluence Cutoff-PL 3.16e-08 3.20e-08 1.84e-08 7.76e-09 8.69e-08 9.38e-08 erg/cm2
Error 3.86e-09 3.20e-09 3.80e-09 1.21e-08 8.60e-09 0.00e+00 erg/cm2
Peak flux Cutoff-PL 3.20e+00 1.86e+00 5.41e-01 1.05e-01 5.67e+00 5.70e+00 ph/cm2/s
Error 4.09e-01 1.81e-01 1.03e-01 1.22e-01 4.90e-01 5.04e-01 ph/cm2/s
Fluence Band 3.11e-08 3.18e-08 1.81e-08 1.47e-08 8.79e-08 9.60e-08 erg/cm2
Error 4.11e-09 3.14e-09 4.53e-09 1.16e-08 8.73e-09 1.37e-08 erg/cm2
Peak flux Band 3.20e+00 1.86e+00 5.41e-01 1.05e-01 5.67e+00 5.70e+00 ph/cm2/s
Error 4.10e-01 1.81e-01 1.03e-01 1.13e-01 4.90e-01 5.05e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.626 0.166 - - 2.76e-02 3.14e-03 55.672 57
CPL 1.980 0.338 1.2 9.9 6.83e-02 1.32e-02 53.780 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.620 0.164 - - 2.74e-02 3.10e-03 58.338 57
CPL 1.958 0.000 2.4 10.2 6.91e-02 1.73e-02 56.063 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: 0.064000 sec.
T50 in the 50-300 keV band: 0.064000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.316 0.048 0.364
T90 0.272 0.056 0.328
T50 0.016 0.252 0.268
Peak 1.000 -0.292 0.708
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
272.1620 -20.3987 0.0087 18.7 68.5 0.1992 22.1 TRIG_00147072
------------------------------------------
Foreground time interval of the image:
0.032 0.348 (delta_t = 0.316 [sec])
Background time interval of the image:
-9.840 0.032 (delta_t = 9.872 [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 0.032 sec. to 0.348 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.62620 ( -0.161551 0.169458 )
Norm@50keV : 2.762194E-02 ( -3.157157E-03 3.117101E-03) )
------------------------------------------------------------
Chi-Squared = 55.67170 using 59 PHA bins.
Reduced chi-squared = 0.9766966 for 57 degrees of freedom
Null hypothesis probability = 0.525
Photon flux (15-150 keV) in 0.3160 sec: 5.87440 ( -0.47523 0.47647 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.05899e-08 ( -7.4971e-09 7.57673e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.032 sec. to 0.348 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.98025 ( -0.663901 1.240933E-02) )
Epeak [keV] : 1.15234 ( -0.808375 19.0482 )
Norm@50keV : 6.830432E-02 ( -1.250581E-02 1.390281E-02) )
------------------------------------------------------------
Chi-Squared = 53.77958 using 59 PHA bins.
but latest trial 1.99266 gives Chi-Squared = 2.74151
but latest trial -0.685352 gives Chi-Squared = 0.209690
Reduced chi-squared = 0.9603496 for 56 degrees of freedom
Null hypothesis probability = 0.559
Photon flux (15-150 keV) in 0.3160 sec: 5.75482 ( -0.49785 0.4967 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.6852e-08 ( -8.49187e-09 8.70801e-09 ) ergs/cm2
Band function
Time interval is from 0.032 sec. to 0.348 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.70147 ( -8.29853 0.564494 )
beta : -9.09442 ( -6.95776 0.488809 )
Epeak [keV] : 14.4600 ( -19.8264 4.53234 )
Norm@50keV : 8.907915E-02 ( -8.591656E-02 11056.4 )
------------------------------------------------------------
Chi-Squared = 55.79805 using 59 PHA bins.
Reduced chi-squared = 1.014510 for 55 degrees of freedom
Null hypothesis probability = 0.445
Photon flux (15-150 keV) in 0.3160 sec: 5.75449 ( -0.49753 0.4977 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.79251e-08 ( -9.39405e-09 8.05958e-09 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.032 sec. to 0.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.61998 ( -0.160543 0.168434 )
Norm@50keV : 2.738058E-02 ( -3.117643E-03 3.077056E-03) )
------------------------------------------------------------
Chi-Squared = 58.33807 using 59 PHA bins.
Reduced chi-squared = 1.023475 for 57 degrees of freedom
Null hypothesis probability = 0.426
Photon flux (15-150 keV) in 0.3200 sec: 5.79974 ( -0.46866 0.46993 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.07462e-08 ( -7.5184e-09 7.59136e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.032 sec. to 0.352 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.95833 ( )
Epeak [keV] : 2.39263 ( -0.131771 20.3492 )
Norm@50keV : 6.906469E-02 ( -2.118804E-02 1.342638E-02) )
------------------------------------------------------------
Chi-Squared = 56.06337 using 59 PHA bins.
but latest trial 2.788249E-02 gives Chi-Squared = 52.7441
Reduced chi-squared = 1.001132 for 56 degrees of freedom
Null hypothesis probability = 0.472
Photon flux (15-150 keV) in 0.3200 sec: 5.67410 ( -0.49025 0.48904 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.67101e-08 ( -8.39968e-09 8.69952e-09 ) ergs/cm2
Band function
Time interval is from 0.032 sec. to 0.352 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.69693 ( -8.30307 0.396077 )
beta : -9.25548 ( -0.826321 0.291179 )
Epeak [keV] : 14.4892 ( -10.9179 13.3348 )
Norm@50keV : 8.908871E-02 ( -0.114573 9334.02 )
------------------------------------------------------------
Chi-Squared = 57.77520 using 59 PHA bins.
Reduced chi-squared = 1.050458 for 55 degrees of freedom
Null hypothesis probability = 0.373
Photon flux (15-150 keV) in 0.3200 sec: 5.67390 ( -0.49004 0.49036 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.95526e-08 ( -6.92704e-09 6.928e-09 ) ergs/cm2
Plot creation:
Mon Jan 7 17:36:12 EST 2008