batgrbproduct Analysis for Trigger=181323
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 Dec 31 12:36:00 EST 2007
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger181323/GCN5_download_cron
======================================================================
Trigger: 00181323 Segment: 000
BAT Trigger Time: 161480560 [s; MET]
Trigger Stop: 161480624 [s; MET]
UTC: 2006-02-12T23:42:38.987760 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 260.99600045478 Dec: -37.6114940906612 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 5.31
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 5.31
Flight Position: [ source = BAT ]
RA: 260.99600045478 Dec: -37.6114940906612 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 261.056875585177 Dec: -37.6355462047481 [deg; J2000]
{ 17h 24m 13.7s , -37d 38' 08.0" }
+/- 4.57871546557487 [arcmin] (estimated 90% radius based on SNR)
+/- 2.33597072329472 [arcmin] (formal 1-sigma fit error)
SNR: 3.46097826013413
RA = 17h 24m 13.7s (261.056876 deg.)
Dec = -37d 38' 8" (-37.635546 deg.)
Angular difference between Flight and Ground position is 3.232902 arcmin
Partial Coding Fraction: 0.2773438 [ 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 0.172669 0.187659 0.019920 -0.016954
0.072219 0.063423 0.052099 0.041726 [error]
Peak 0.172669 0.187659 0.019920 -0.016954
0.072219 0.063423 0.052099 0.041726 [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 7.94e-08 6.73e-08 3.89e-08 3.36e-08 2.00e-07 2.19e-07 erg/cm2
Error 4.31e-08 3.63e-08 4.13e-08 6.96e-08 1.05e-07 1.38e-07 erg/cm2
Peak flux Power-law 8.16e-02 3.88e-02 1.12e-02 4.07e-03 1.34e-01 1.36e-01 ph/cm2/s
Error 4.51e-02 2.03e-02 8.82e-03 7.70e-03 6.24e-02 6.32e-02 ph/cm2/s
Fluence Cutoff-PL 6.73e-08 8.88e-08 3.17e-08 1.80e-09 1.90e-07 1.89e-07 erg/cm2
Error 4.86e-08 5.16e-08 4.27e-08 5.18e-08 9.77e-08 1.18e-07 erg/cm2
Peak flux Cutoff-PL 6.74e-02 5.08e-02 9.74e-03 3.01e-04 1.28e-01 1.28e-01 ph/cm2/s
Error 5.06e-02 2.85e-02 1.24e-02 5.86e-03 6.27e-02 6.28e-02 ph/cm2/s
Fluence Band 6.77e-08 8.89e-08 3.14e-08 1.74e-09 1.89e-07 1.87e-07 erg/cm2
Error 4.60e-08 4.65e-08 3.76e-08 2.88e-08 8.65e-08 0.00e+00 erg/cm2
Peak flux Band 5.44e-02 5.53e-02 6.24e-03 3.84e-05 1.16e-01 1.16e-01 ph/cm2/s
Error 7.55e-02 2.85e-02 1.22e-02 5.62e-03 4.63e-02 5.71e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.791 1.058 - - 5.65e-04 4.98e-04 43.210 57
CPL 0.386 4.147 25.7 24.1 1.64e-02 7.66e-01 42.064 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.791 1.058 - - 5.65e-04 4.98e-04 43.210 57
CPL 0.386 3.293 25.7 24.1 1.64e-02 7.66e-01 42.064 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
261.0569 -37.6355 0.0558 49.7 -11.4 0.4508 3.5 TRIG_00181323
------------------------------------------
Foreground time interval of the image:
0.000 28.150 (delta_t = 28.150 [sec])
29.000 33.111 (delta_t = 4.111 [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
Multiple GTIs in the spectrum
tstart tstop
0.000000 28.150000
29.000000 33.111300
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.79058 ( -0.828997 1.28784 )
Norm@50keV : 5.645131E-04 ( -5.645131E-04 4.314365E-04) )
------------------------------------------------------------
Chi-Squared = 43.20955 using 59 PHA bins.
Reduced chi-squared = 0.7580622 for 57 degrees of freedom
Null hypothesis probability = 0.911
Photon flux (15-150 keV) in 32.26 sec: 0.133892 ( -0.0624183 0.06246 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.00295e-07 ( -1.00724e-07 1.09865e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
0.000000 28.150000
29.000000 33.111300
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.385960 ( -3.38596 4.90726 )
Epeak [keV] : 25.6765 ( -25.6665 22.5724 )
Norm@50keV : 1.640210E-02 ( -1.640210E-02 1.51509 )
------------------------------------------------------------
Chi-Squared = 42.06380 using 59 PHA bins.
but latest trial 1.55687 gives Chi-Squared = 0.861828
Reduced chi-squared = 0.7511392 for 56 degrees of freedom
Null hypothesis probability = 0.916
Photon flux (15-150 keV) in 32.26 sec: 0.128201 ( -0.0623299 0.063155 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.89638e-07 ( -9.02586e-08 1.05138e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
0.000000 28.150000
29.000000 33.111300
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.82416 ( -4.84518 0.557946 )
beta : -9.27855 ( -0.721453 7.19011 )
Epeak [keV] : 7.08992 ( -6.98992 42.8233 )
Norm@50keV : 2.219698E-03 ( -2.219698E-03 750.867 )
------------------------------------------------------------
Chi-Squared = 42.41550 using 59 PHA bins.
Reduced chi-squared = 0.7711909 for 55 degrees of freedom
Null hypothesis probability = 0.893
Photon flux (15-150 keV) in 32.26 sec: 0.115964 ( -0.0265543 0.066022 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.89078e-07 ( -8.65829e-08 8.64771e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 29.000 sec. to 33.111 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.79058 ( -0.828997 1.28784 )
Norm@50keV : 5.645131E-04 ( -5.645131E-04 4.314365E-04) )
------------------------------------------------------------
Chi-Squared = 43.20955 using 59 PHA bins.
Reduced chi-squared = 0.7580622 for 57 degrees of freedom
Null hypothesis probability = 0.911
Photon flux (15-150 keV) in 32.26 sec: 0.133892 ( -0.0624183 0.06246 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.00295e-07 ( -1.00724e-07 1.09865e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 29.000 sec. to 33.111 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.385960 ( -3.38596 3.20008 )
Epeak [keV] : 25.6765 ( -25.6665 22.5724 )
Norm@50keV : 1.640210E-02 ( -1.640210E-02 1.51509 )
------------------------------------------------------------
Chi-Squared = 42.06380 using 59 PHA bins.
but latest trial 1.55687 gives Chi-Squared = 0.861828
Reduced chi-squared = 0.7511392 for 56 degrees of freedom
Null hypothesis probability = 0.916
Photon flux (15-150 keV) in 32.26 sec: 0.128201 ( -0.0623299 0.063155 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.89638e-07 ( -9.02586e-08 1.05138e-07 ) ergs/cm2
Band function
Time interval is from 29.000 sec. to 33.111 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.82416 ( -4.84518 0.557946 )
beta : -9.27855 ( -0.721453 7.19011 )
Epeak [keV] : 7.08992 ( -6.98992 42.8233 )
Norm@50keV : 2.219698E-03 ( -2.219698E-03 750.867 )
------------------------------------------------------------
Chi-Squared = 42.41550 using 59 PHA bins.
Reduced chi-squared = 0.7711909 for 55 degrees of freedom
Null hypothesis probability = 0.893
Photon flux (15-150 keV) in 32.26 sec: 0.115964 ( -0.0265543 0.066022 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.89078e-07 ( -8.65829e-08 8.64771e-08 ) ergs/cm2
Plot creation:
Mon Dec 31 12:40:24 EST 2007