batgrbproduct Analysis for Trigger=312072
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 May 21 18:53:29 EDT 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger312072/GCN5_download_cron
======================================================================
Trigger: 00312072 Segment: 000
BAT Trigger Time: 233051560 [s; MET]
Trigger Stop: 233051880 [s; MET]
UTC: 2008-05-21T08:32:37.193600 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 47.046290056391 Dec: 40.9585042728924 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 8.4
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 8.4
Flight Position: [ source = BAT ]
RA: 47.046290056391 Dec: 40.9585042728924 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 47.0829666017602 Dec: 40.927606222476 [deg; J2000]
{ 03h 08m 19.9s , +40d 55' 39.4" }
+/- 2.82522682305743 [arcmin] (estimated 90% radius based on SNR)
+/- 1.32241602657251 [arcmin] (formal 1-sigma fit error)
SNR: 6.89852898009542
Angular difference between Flight and Ground position is 2.489966 arcmin
Partial Coding Fraction: 0.2578125 [ including projection effects ]
Duration
T90: 320 +/-
Measured from: 0
to: 320 [s; relative to TRIGTIME]
T50: 320 +/-
Measured from: 0
to: 320 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 320 second)
Measured from: 0
to: 320 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 320 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.882460 0.853997 0.193426 -0.211269
0.176980 0.179229 0.171045 0.178935 [error]
Peak 1.882460 0.853997 0.193426 -0.211269
0.176980 0.179229 0.171045 0.178935 [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 6.27e-07 3.92e-07 1.58e-07 8.61e-08 1.22e-06 1.26e-06 erg/cm2
Error 1.09e-07 1.07e-07 9.30e-08 1.08e-07 2.62e-07 3.04e-07 erg/cm2
Peak flux Power-law 6.93e-02 2.45e-02 4.94e-03 1.18e-03 9.95e-02 9.99e-02 ph/cm2/s
Error 1.23e-02 6.34e-03 2.82e-03 1.40e-03 1.63e-02 1.65e-02 ph/cm2/s
Fluence Cutoff-PL 6.33e-07 3.94e-07 1.11e-07 1.61e-08 1.15e-06 1.14e-06 erg/cm2
Error 1.17e-07 1.38e-07 1.31e-07 1.03e-07 2.98e-07 3.35e-07 erg/cm2
Peak flux Cutoff-PL 6.93e-02 2.45e-02 4.93e-03 1.17e-03 9.95e-02 9.99e-02 ph/cm2/s
Error 1.23e-02 6.34e-03 2.81e-03 1.39e-03 1.63e-02 1.64e-02 ph/cm2/s
Fluence Band 6.16e-07 3.98e-07 1.63e-07 9.08e-08 1.22e-06 1.30e-06 erg/cm2
Error 1.02e-07 4.34e-08 1.04e-07 2.08e-07 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 7.31e-02 2.35e-02 3.60e-03 6.30e-04 1.01e-01 1.01e-01 ph/cm2/s
Error 1.29e-02 6.80e-03 2.39e-03 1.27e-03 1.63e-02 1.68e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.254 0.508 - - 3.00e-04 1.28e-04 60.328 57
CPL 1.676 0.000 4.9 0.0 5.06e-03 6.03e+00 60.363 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 3.254 0.508 - - 3.00e-04 1.28e-04 60.328 57
CPL 1.676 0.000 4.9 0.0 5.06e-03 6.03e+00 60.363 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 320.000 0.000 320.000
T90 320.000 0.000 320.000
T50 320.000 0.000 320.000
Peak 320.000 0.000 320.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
47.0830 +40.9276 0.0274 35.8 -105.5 3.2788 6.9 TRIG_00312072
------------------------------------------
Foreground time interval of the image:
0.000 303.025 (delta_t = 303.025 [sec])
Background time interval of the image:
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 0.000 sec. to 303.026 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.25425 ( -0.409507 0.606892 )
Norm@50keV : 3.000026E-04 ( -1.317169E-04 1.240447E-04) )
------------------------------------------------------------
Chi-Squared = 60.32803 using 59 PHA bins.
Reduced chi-squared = 1.058386 for 57 degrees of freedom
Null hypothesis probability = 0.356
Photon flux (15-150 keV) in 303.0 sec: 9.952227E-02 ( -0.0162732 0.0163067 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.2209e-06 ( -2.50739e-07 2.73215e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 303.026 sec.
Photon index: 1.67644 ( )
Epeak [keV] : 4.90500 ( )
Norm@50keV : 5.060060E-03 ( -1.600539E-03 12.0507 )
------------------------------------------------------------
Chi-Squared = 60.36256 using 59 PHA bins.
but latest trial -2.27321 gives Chi-Squared = 1.74940
but latest trial 1.646016E-03 gives Chi-Squared = 2.77533
but latest trial 5.08931 gives Chi-Squared = 1.77017
Reduced chi-squared = 1.077903 for 56 degrees of freedom
Null hypothesis probability = 0.321
Photon flux (15-150 keV) in 303.0 sec: 9.947442E-02 ( -0.0162667 0.0162996 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.15191e-06 ( -2.79318e-07 3.16768e-07 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 303.026 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.40004 ( -7.83707 0.381446 )
beta : -9.28205 ( )
Epeak [keV] : 11.7107 ( )
Norm@50keV : 4.399326E-03 ( )
------------------------------------------------------------
Chi-Squared = 63.51592 using 59 PHA bins.
Reduced chi-squared = 1.154835 for 55 degrees of freedom
Null hypothesis probability = 0.201
Photon flux (15-150 keV) in 303.0 sec: 0.100609 ( -0.016564 0.016073 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.21761e-06 ( -2.16515e-07 1.99047e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 303.026 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.25425 ( -0.409507 0.606892 )
Norm@50keV : 3.000026E-04 ( -1.317169E-04 1.240447E-04) )
------------------------------------------------------------
Chi-Squared = 60.32803 using 59 PHA bins.
Reduced chi-squared = 1.058386 for 57 degrees of freedom
Null hypothesis probability = 0.356
Photon flux (15-150 keV) in 303.0 sec: 9.952227E-02 ( -0.0162732 0.0163067 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.2209e-06 ( -2.50739e-07 2.73215e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 303.026 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.67644 ( )
Epeak [keV] : 4.90500 ( )
Norm@50keV : 5.060060E-03 ( -3.327582E-03 12.0512 )
------------------------------------------------------------
Chi-Squared = 60.36256 using 59 PHA bins.
but latest trial -2.27321 gives Chi-Squared = 1.74940
but latest trial 5.12758 gives Chi-Squared = 1.76753
Reduced chi-squared = 1.077903 for 56 degrees of freedom
Null hypothesis probability = 0.321
Photon flux (15-150 keV) in 303.0 sec: 9.947442E-02 ( -0.0162667 0.0162996 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.15191e-06 ( -2.79318e-07 3.16768e-07 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 303.026 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.40004 ( -7.83707 0.381446 )
beta : -9.28205 ( -0.545743 13.3121 )
Epeak [keV] : 11.7107 ( -11.6107 9988.29 )
Norm@50keV : 4.399326E-03 ( -6.890813E-02 0.400645 )
------------------------------------------------------------
Chi-Squared = 63.51592 using 59 PHA bins.
Reduced chi-squared = 1.154835 for 55 degrees of freedom
Null hypothesis probability = 0.201
Photon flux (15-150 keV) in 303.0 sec: 0.100609 ( -0.016564 0.016073 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.21761e-06 ( -2.16515e-07 1.99047e-07 ) ergs/cm2
Plot creation:
Wed May 21 19:27:47 EDT 2008