batgrbproduct Analysis for Trigger=162526
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 9 17:19:44 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger162526/GCN5_download_cron
======================================================================
Trigger: 00162526 Segment: 000
BAT Trigger Time: 152836008 [s; MET]
Trigger Stop: 152836120 [s; MET]
UTC: 2005-11-04T22:26:48.178460 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 281.241144350066 Dec: -4.62558651122299 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 33311
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 33311
Flight Position: [ source = BAT ]
RA: 281.241144350066 Dec: -4.62558651122299 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 281.329225666512 Dec: -4.3971006610392 [deg; J2000]
{ 18h 45m 19.0s , -04d 23' 49.6" }
+/- 7.14999941250416 [arcmin] (estimated 90% radius based on SNR)
+/- 5.71987636502499 [arcmin] (formal 1-sigma fit error)
SNR: 1.83096999933329
RA = 18h 45m 19.0s (281.329226 deg.)
Dec = -4d 23' 50" (-4.397101 deg.)
Angular difference between Flight and Ground position is 14.686658 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 112 +/-
Measured from: 0
to: 112 [s; relative to TRIGTIME]
T50: 112 +/-
Measured from: 0
to: 112 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 112 second)
Measured from: 0
to: 112 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 112 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.076698 0.062294 0.017831 0.010822
0.027329 0.027025 0.023290 0.019611 [error]
Peak 0.076698 0.062294 0.017831 0.010822
0.027329 0.027025 0.023290 0.019611 [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 1.94e-08 2.53e-08 2.41e-08 4.08e-08 8.23e-08 1.09e-07 erg/cm2
Error 1.14e-08 1.24e-08 2.07e-08 8.32e-08 4.86e-08 1.05e-07 erg/cm2
Peak flux Power-law 1.92e-02 1.38e-02 6.58e-03 4.42e-03 4.17e-02 4.40e-02 ph/cm2/s
Error 1.15e-02 6.57e-03 6.24e-03 8.14e-03 1.87e-02 2.04e-02 ph/cm2/s
Fluence Cutoff-PL 1.94e-08 2.56e-08 2.42e-08 3.67e-08 8.21e-08 9.57e-08 erg/cm2
Error 1.14e-08 1.54e-08 2.34e-08 8.26e-08 6.71e-08 1.01e-07 erg/cm2
Peak flux Cutoff-PL 1.92e-02 1.38e-02 6.58e-03 4.39e-03 4.17e-02 4.40e-02 ph/cm2/s
Error 1.15e-02 6.57e-03 6.25e-03 8.09e-03 1.87e-02 2.04e-02 ph/cm2/s
Fluence Band 2.00e-08 2.55e-08 2.24e-08 3.39e-08 8.01e-08 1.10e-07 erg/cm2
Error 1.59e-08 1.30e-08 2.02e-08 7.50e-08 4.16e-08 0.00e+00 erg/cm2
Peak flux Band 1.92e-02 1.38e-02 6.58e-03 4.39e-03 4.17e-02 4.40e-02 ph/cm2/s
Error 1.16e-02 6.57e-03 6.24e-03 8.09e-03 1.87e-02 2.08e-02 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.070 1.050 - - 2.69e-04 2.18e-04 52.273 57
CPL 1.387 0.000 35.2 4999.1 6.92e-04 2.00e-01 52.390 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.070 1.050 - - 2.69e-04 2.18e-04 52.273 57
CPL 1.387 0.000 35.2 4999.5 6.92e-04 2.00e-01 52.390 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 112.000 0.000 112.000
T90 112.000 0.000 112.000
T50 112.000 0.000 112.000
Peak 112.000 0.000 112.000
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
281.3292 -4.3971 0.1049 12.0 -139.5 0.1034 1.8 TRIG_00162526
------------------------------------------
Foreground time interval of the image:
0.000 33.027 (delta_t = 33.027 [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 33.027 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.06980 ( -0.880735 1.21888 )
Norm@50keV : 2.688658E-04 ( -2.688658E-04 1.668690E-04) )
------------------------------------------------------------
Chi-Squared = 52.27349 using 59 PHA bins.
Reduced chi-squared = 0.9170787 for 57 degrees of freedom
Null hypothesis probability = 0.653
Photon flux (15-150 keV) in 33.03 sec: 4.167901E-02 ( -0.0186677 0.0186801 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.22926e-08 ( -4.52283e-08 5.1946e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.027 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38655 ( )
Epeak [keV] : 35.1876 ( -31.9949 9966.10 )
Norm@50keV : 6.923201E-04 ( -4.052869E-04 0.399169 )
------------------------------------------------------------
Chi-Squared = 52.39037 using 59 PHA bins.
but latest trial 4.41088 gives Chi-Squared = 5.798340E-03
Reduced chi-squared = 0.9355423 for 56 degrees of freedom
Null hypothesis probability = 0.612
Photon flux (15-150 keV) in 33.03 sec: 4.166614E-02 ( -0.0186622 0.0186745 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.21238e-08 ( -8.21238e-08 5.21402e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.027 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.59168 ( -14.1610 0.839025 )
beta : -9.29072 ( -2.60592 0.973349 )
Epeak [keV] : 34.1048 ( -20.7282 355.731 )
Norm@50keV : 5.181971E-04 ( -32.7389 387.965 )
------------------------------------------------------------
Chi-Squared = 52.33734 using 59 PHA bins.
Reduced chi-squared = 0.9515880 for 55 degrees of freedom
Null hypothesis probability = 0.577
Photon flux (15-150 keV) in 33.03 sec: 4.166622E-02 ( -0.0186623 0.0186745 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.00862e-08 ( -4.34629e-08 3.98276e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.027 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.06980 ( -0.880735 1.21888 )
Norm@50keV : 2.688658E-04 ( -2.688658E-04 1.668690E-04) )
------------------------------------------------------------
Chi-Squared = 52.27349 using 59 PHA bins.
Reduced chi-squared = 0.9170787 for 57 degrees of freedom
Null hypothesis probability = 0.653
Photon flux (15-150 keV) in 33.03 sec: 4.167901E-02 ( -0.0186677 0.0186801 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.22926e-08 ( -4.52283e-08 5.1946e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.027 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38655 ( )
Epeak [keV] : 35.1876 ( -32.4658 9966.50 )
Norm@50keV : 6.923201E-04 ( -3.935199E-04 0.399281 )
------------------------------------------------------------
Chi-Squared = 52.39037 using 59 PHA bins.
but latest trial 3.56038 gives Chi-Squared = 4.981995E-03
Reduced chi-squared = 0.9355423 for 56 degrees of freedom
Null hypothesis probability = 0.612
Photon flux (15-150 keV) in 33.03 sec: 4.166614E-02 ( -0.0186622 0.0186745 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.21238e-08 ( -8.21238e-08 5.21402e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.027 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.59168 ( -14.1610 0.839025 )
beta : -9.29072 ( -2.60592 0.973349 )
Epeak [keV] : 34.1048 ( -20.7282 355.731 )
Norm@50keV : 5.181971E-04 ( -32.7389 387.965 )
------------------------------------------------------------
Chi-Squared = 52.33734 using 59 PHA bins.
Reduced chi-squared = 0.9515880 for 55 degrees of freedom
Null hypothesis probability = 0.577
Photon flux (15-150 keV) in 33.03 sec: 4.166622E-02 ( -0.0186623 0.0186745 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.00862e-08 ( -4.34629e-08 3.98276e-08 ) ergs/cm2
Plot creation:
Wed Jan 9 17:24:44 EST 2008