batgrbproduct Analysis for Trigger=225891
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 2 01:32:19 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger225891/GCN5_download_cron
======================================================================
Trigger: 00225891 Segment: 000
BAT Trigger Time: 177904245.088 [s; MET]
Trigger Stop: 177904245.472 [s; MET]
UTC: 2006-08-22T01:50:43.692620 [includes UTCF correction]
Where From?: (*SHORT BURST*) Expanded to TRIGTIME - 32 ms to TRIGTIME + 320 ms
BAT
RA: 234.244027353801 Dec: -57.8535147397321 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 5.83
Image Trigger?: NO
Rate S/N Ratio: 9.64365076099295 [ if not an image trigger ]
Image S/N Ratio: 5.83
Flight Position: [ source = BAT ]
RA: 234.244027353801 Dec: -57.8535147397321 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 234.395552378619 Dec: -57.9759244593607 [deg; J2000]
{ 15h 37m 34.9s , -57d 58' 33.3" }
+/- 4.14675700390082 [arcmin] (estimated 90% radius based on SNR)
+/- 2.7681816683484 [arcmin] (formal 1-sigma fit error)
SNR: 3.98728741177426
RA = 15h 37m 34.9s (234.395552 deg.)
Dec = -57d 58' 33" (-57.975924 deg.)
Angular difference between Flight and Ground position is 8.790011 arcmin
Partial Coding Fraction: 0.875 [ including projection effects ]
Duration
T90: 0.38400000333786 +/-
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
T50: 0.38400000333786 +/-
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 0.38400000333786 second)
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 0.38400000333786 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.004473 -0.001191 0.004229 0.007120
0.003206 0.003246 0.002854 0.002554 [error]
Peak 0.004473 -0.001191 0.004229 0.007120
0.003206 0.003246 0.002854 0.002554 [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 1.19e-10 6.11e-10 2.74e-09 4.96e-08 8.42e-09 4.94e-08 erg/cm2
Error 6.26e-10 1.20e-09 2.68e-09 1.05e-07 7.55e-09 1.06e-07 erg/cm2
Peak flux Power-law 9.54e-03 2.64e-02 5.91e-02 3.51e-01 1.59e-01 4.46e-01 ph/cm2/s
Error 5.27e-02 5.46e-02 5.91e-02 6.49e-01 1.77e-01 6.72e-01 ph/cm2/s
Fluence Cutoff-PL 9.09e-11 4.85e-10 2.93e-09 2.07e-08 8.78e-09 4.32e-08 erg/cm2
Error 3.18e-09 1.47e-07 7.75e-09 1.14e-07 0.00e+00 0.00e+00 erg/cm2
Peak flux Cutoff-PL 9.46e-03 2.63e-02 5.91e-02 3.50e-01 1.59e-01 4.45e-01 ph/cm2/s
Error 5.26e-02 5.45e-02 5.92e-02 7.02e-01 1.77e-01 7.21e-01 ph/cm2/s
Fluence Band 1.07e-11 2.41e-10 2.84e-09 1.48e-08 8.92e-09 1.84e-08 erg/cm2
Error 2.60e-09 5.57e-08 7.81e-09 1.02e-07 0.00e+00 0.00e+00 erg/cm2
Peak flux Band 9.46e-03 1.99e-02 6.00e-02 1.51e-01 1.45e-01 4.45e-01 ph/cm2/s
Error 6.15e-02 1.23e+00 1.05e-01 7.22e-01 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 -0.163 2.522 - - 1.11e-03 1.54e-03 54.793 57
CPL -0.187 2.522 9995.3 5000.0 1.12e-03 1.55e-03 54.791 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL -0.163 2.522 - - 1.11e-03 1.54e-03 54.793 57
CPL -0.187 2.522 9995.3 5000.0 1.12e-03 1.55e-03 54.791 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 0.384 0.000 0.384
T90 0.384 0.000 0.384
T50 0.384 0.000 0.384
Peak 0.384 0.000 0.384
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
234.3956 -57.9759 0.0482 27.2 -23.9 0.0230 4.0 TRIG_00225891
------------------------------------------
Foreground time interval of the image:
-0.032 0.352 (delta_t = 0.384 [sec])
Background time interval of the image:
-10.120 -5.120 (delta_t = 5.000 [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 0.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.163000 ( -2.83700 2.20766 )
Norm@50keV : 1.108555E-03 ( -1.108555E-03 1.972589E-03) )
------------------------------------------------------------
Chi-Squared = 54.79320 using 59 PHA bins.
Reduced chi-squared = 0.9612842 for 57 degrees of freedom
Null hypothesis probability = 0.558
Photon flux (15-150 keV) in 0.3840 sec: 0.159275 ( -0.159275 0.194371 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.41874e-09 ( -8.41874e-09 6.68943e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.186556 ( -2.81344 2.22969 )
Epeak [keV] : 9995.33 ( -9995.32 4.66895 )
Norm@50keV : 1.117682E-03 ( -1.117682E-03 1.981860E-03) )
------------------------------------------------------------
Chi-Squared = 54.79145 using 59 PHA bins.
Reduced chi-squared = 0.9784188 for 56 degrees of freedom
Null hypothesis probability = 0.521
Photon flux (15-150 keV) in 0.3840 sec: 0.159212 ( -0.159212 0.194159 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.78465e-09 ( -8.78465e-09 6.72238e-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 : -0.306614 ( -9.69339 5.30661 )
beta : 0.162867 ( -2.20556 9.83713 )
Epeak [keV] : 15.0521 ( -14.9521 9984.95 )
Norm@50keV : 1.926168E-03 ( -1.926168E-03 388441. )
------------------------------------------------------------
Chi-Squared = 54.79320 using 59 PHA bins.
Reduced chi-squared = 0.9962400 for 55 degrees of freedom
Null hypothesis probability = 0.482
Photon flux (15-150 keV) in 0.3840 sec: 0.145364 ( -0.145364 0.064135 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.92332e-09 ( -8.92332e-09 6.69059e-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: -0.163000 ( -2.83700 2.20766 )
Norm@50keV : 1.108555E-03 ( -1.108555E-03 1.972589E-03) )
------------------------------------------------------------
Chi-Squared = 54.79320 using 59 PHA bins.
Reduced chi-squared = 0.9612842 for 57 degrees of freedom
Null hypothesis probability = 0.558
Photon flux (15-150 keV) in 0.3840 sec: 0.159275 ( -0.159275 0.194371 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.41874e-09 ( -8.41874e-09 6.68943e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 0.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.186556 ( -2.81344 2.22969 )
Epeak [keV] : 9995.33 ( -9995.32 4.66895 )
Norm@50keV : 1.117682E-03 ( -1.117682E-03 1.981860E-03) )
------------------------------------------------------------
Chi-Squared = 54.79145 using 59 PHA bins.
Reduced chi-squared = 0.9784188 for 56 degrees of freedom
Null hypothesis probability = 0.521
Photon flux (15-150 keV) in 0.3840 sec: 0.159212 ( -0.159212 0.194159 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.78465e-09 ( -8.78465e-09 6.72238e-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 : -0.306614 ( -9.69339 5.30661 )
beta : 0.162867 ( -2.20556 9.83713 )
Epeak [keV] : 15.0521 ( -14.9521 9984.95 )
Norm@50keV : 1.926168E-03 ( -1.926168E-03 388441. )
------------------------------------------------------------
Chi-Squared = 54.79320 using 59 PHA bins.
Reduced chi-squared = 0.9962400 for 55 degrees of freedom
Null hypothesis probability = 0.482
Photon flux (15-150 keV) in 0.3840 sec: 0.145364 ( -0.145364 0.064135 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.92332e-09 ( -8.92332e-09 6.69059e-09 ) ergs/cm2
Plot creation:
Wed Jan 2 01:36:57 EST 2008