batgrbproduct Analysis for Trigger=147857
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): Tue Jan 8 10:02:04 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger147857/GCN5_download_cron
======================================================================
Trigger: 00147857 Segment: 000
BAT Trigger Time: 144099216 [s; MET]
Trigger Stop: 144099280 [s; MET]
UTC: 2005-07-26T19:33:36.357900 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 267.672799369352 Dec: -37.1001520453208 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 33288
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 33288
Flight Position: [ source = BAT ]
RA: 267.672799369352 Dec: -37.1001520453208 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 267.73745493744 Dec: -36.9955953984258 [deg; J2000]
{ 17h 50m 57.0s , -36d 59' 44.1" }
+/- 5.48002372464462 [arcmin] (estimated 90% radius based on SNR)
+/- 3.49822592187786 [arcmin] (formal 1-sigma fit error)
SNR: 2.67741009269979
RA = 17h 50m 57.0s (267.737455 deg.)
Dec = -36d 59' 44" (-36.995595 deg.)
Angular difference between Flight and Ground position is 6.995864 arcmin
Partial Coding Fraction: 0.703125 [ including projection effects ]
Duration
T90: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
T50: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 64 second)
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.153584 0.055793 0.020047 -0.043771
0.041975 0.034960 0.031236 0.032034 [error]
Peak 0.153584 0.055793 0.020047 -0.043771
0.041975 0.034960 0.031236 0.032034 [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 4.33e-08 3.29e-08 1.67e-08 1.21e-08 9.84e-08 1.05e-07 erg/cm2
Error 2.00e-08 2.58e-08 2.18e-08 3.75e-08 5.41e-08 7.45e-08 erg/cm2
Peak flux Power-law 4.36e-02 1.86e-02 4.72e-03 1.47e-03 6.78e-02 6.84e-02 ph/cm2/s
Error 2.07e-02 1.44e-02 5.97e-03 4.05e-03 2.77e-02 2.82e-02 ph/cm2/s
Fluence Cutoff-PL 4.33e-08 3.30e-08 1.65e-08 1.09e-08 9.81e-08 1.02e-07 erg/cm2
Error 2.06e-08 2.00e-08 2.18e-08 3.72e-08 5.19e-08 7.46e-08 erg/cm2
Peak flux Cutoff-PL 4.36e-02 1.86e-02 4.72e-03 1.46e-03 6.78e-02 6.84e-02 ph/cm2/s
Error 2.07e-02 1.44e-02 5.96e-03 4.02e-03 2.77e-02 2.82e-02 ph/cm2/s
Fluence Band 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.983 1.353 - - 2.50e-04 2.51e-04 40.560 57
CPL 1.904 3.120 3.3 0.0 1.16e-03 2.52e-04 40.809 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.983 1.353 - - 2.50e-04 2.51e-04 40.560 57
CPL 1.904 2.872 3.3 0.0 1.16e-03 2.52e-04 40.809 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 64.000 0.000 64.000
T90 64.000 0.000 64.000
T50 64.000 0.000 64.000
Peak 64.000 0.000 64.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
267.7375 -36.9956 0.0718 20.5 117.8 0.2079 2.7 TRIG_00147857
------------------------------------------
Foreground time interval of the image:
0.000 33.030 (delta_t = 33.030 [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 33.030 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.98267 ( -1.00008 1.70612 )
Norm@50keV : 2.502056E-04 ( -2.502056E-04 2.514906E-04) )
------------------------------------------------------------
Chi-Squared = 40.55974 using 59 PHA bins.
Reduced chi-squared = 0.7115744 for 57 degrees of freedom
Null hypothesis probability = 0.951
Photon flux (15-150 keV) in 33.03 sec: 6.782592E-02 ( -0.0276941 0.0277516 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.84235e-08 ( -4.92461e-08 5.90104e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.030 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.90391 ( -2.77924 3.46156 )
Epeak [keV] : 3.28779 ( )
Norm@50keV : 1.160045E-03 ( -2.558426E-04 2.473885E-04) )
------------------------------------------------------------
Chi-Squared = 40.80915 using 59 PHA bins.
but latest trial -0.874094 gives Chi-Squared = 1.65004
but latest trial -1.39186 gives Chi-Squared = 5.414200E-02
Reduced chi-squared = 0.7287348 for 56 degrees of freedom
Null hypothesis probability = 0.936
Photon flux (15-150 keV) in 33.03 sec: 6.779795E-02 ( -0.0276839 0.027741 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.80988e-08 ( -4.44019e-08 5.9413e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.030 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.40460 ( -0.411867 14.5881 )
beta : -9.22596 ( )
Epeak [keV] : 15.3910 ( )
Norm@50keV : 2.118926E-03 ( )
------------------------------------------------------------
Chi-Squared = 41.10608 using 59 PHA bins.
Reduced chi-squared = 0.7473832 for 55 degrees of freedom
Null hypothesis probability = 0.918
Photon flux (15-150 keV) in 33.03 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.030 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.98267 ( -1.00008 1.70612 )
Norm@50keV : 2.502056E-04 ( -2.502056E-04 2.514906E-04) )
------------------------------------------------------------
Chi-Squared = 40.55974 using 59 PHA bins.
Reduced chi-squared = 0.7115744 for 57 degrees of freedom
Null hypothesis probability = 0.951
Photon flux (15-150 keV) in 33.03 sec: 6.782592E-02 ( -0.0276941 0.0277516 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.84235e-08 ( -4.92461e-08 5.90104e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.030 sec.
Parameters : value lower 90% higher 90%
Photon index: 1.90391 ( -2.77924 2.96414 )
Epeak [keV] : 3.28779 ( )
Norm@50keV : 1.160045E-03 ( -2.558426E-04 2.473885E-04) )
------------------------------------------------------------
Chi-Squared = 40.80915 using 59 PHA bins.
but latest trial -0.874094 gives Chi-Squared = 1.65004
but latest trial -1.39186 gives Chi-Squared = 5.414200E-02
Reduced chi-squared = 0.7287348 for 56 degrees of freedom
Null hypothesis probability = 0.936
Photon flux (15-150 keV) in 33.03 sec: 6.779795E-02 ( -0.0276839 0.027741 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.80988e-08 ( -4.44019e-08 5.9413e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.030 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.40460 ( -0.411867 14.5881 )
beta : -9.22596 ( )
Epeak [keV] : 15.3910 ( )
Norm@50keV : 2.118926E-03 ( )
------------------------------------------------------------
Chi-Squared = 41.10608 using 59 PHA bins.
Reduced chi-squared = 0.7473832 for 55 degrees of freedom
Null hypothesis probability = 0.918
Photon flux (15-150 keV) in 33.03 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Tue Jan 8 10:25:30 EST 2008