batgrbproduct Analysis for Trigger=157253
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 13:53:46 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger157253/GCN5_download_cron
======================================================================
Trigger: 00157253 Segment: 000
BAT Trigger Time: 149497376 [s; MET]
Trigger Stop: 149497440 [s; MET]
UTC: 2005-09-27T07:02:56.248740 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 261.298147802294 Dec: -36.3130361928939 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 33331
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 33331
Flight Position: [ source = BAT ]
RA: 261.298147802294 Dec: -36.3130361928939 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 261.386125118973 Dec: -36.3164805866052 [deg; J2000]
{ 17h 25m 32.7s , -36d 18' 59.3" }
+/- 5.08693071613032 [arcmin] (estimated 90% radius based on SNR)
+/- 3.84647920527528 [arcmin] (formal 1-sigma fit error)
SNR: 2.97780171898289
RA = 17h 25m 32.7s (261.386125 deg.)
Dec = -36d 18' 59" (-36.316481 deg.)
Angular difference between Flight and Ground position is 4.258417 arcmin
Partial Coding Fraction: 1.015625 [ 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 0.110029 0.076566 0.025977 -0.011369
0.031384 0.028663 0.024972 0.024056 [error]
Peak 0.110029 0.076566 0.025977 -0.011369
0.031384 0.028663 0.024972 0.024056 [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 2.75e-08 2.76e-08 1.94e-08 2.17e-08 8.31e-08 9.63e-08 erg/cm2
Error 1.29e-08 1.33e-08 1.98e-08 4.23e-08 4.36e-08 6.83e-08 erg/cm2
Peak flux Power-law 2.74e-02 1.53e-02 5.39e-03 2.48e-03 4.94e-02 5.06e-02 ph/cm2/s
Error 1.31e-02 7.17e-03 5.37e-03 4.43e-03 2.04e-02 2.12e-02 ph/cm2/s
Fluence Cutoff-PL 2.82e-08 3.57e-08 3.88e-09 6.80e-12 6.82e-08 6.80e-08 erg/cm2
Error 1.38e-08 1.39e-08 1.24e-08 8.26e-09 2.77e-08 2.79e-08 erg/cm2
Peak flux Cutoff-PL 2.70e-02 2.06e-02 1.31e-03 1.28e-06 4.89e-02 4.89e-02 ph/cm2/s
Error 1.36e-02 9.82e-03 3.50e-03 1.07e-03 1.85e-02 1.85e-02 ph/cm2/s
Fluence Band 2.70e-08 3.27e-08 1.37e-08 5.20e-09 7.72e-08 7.68e-08 erg/cm2
Error 1.39e-08 1.65e-08 1.56e-08 2.79e-08 3.70e-08 5.59e-08 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 2.507 0.883 - - 2.50e-04 2.13e-04 62.292 57
CPL -2.499 0.000 26.7 7.7 7.87e-01 3.89e+00 59.413 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.507 0.883 - - 2.50e-04 2.13e-04 62.292 57
CPL -2.499 0.000 26.7 7.7 7.87e-01 3.89e+00 59.413 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 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
261.3861 -36.3165 0.0642 12.2 -147.9 0.1721 3.0 TRIG_00157253
------------------------------------------
Foreground time interval of the image:
0.000 33.098 (delta_t = 33.098 [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 33.098 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.50705 ( -0.762391 1.00403 )
Norm@50keV : 2.504377E-04 ( -2.504377E-04 1.747289E-04) )
------------------------------------------------------------
Chi-Squared = 62.29200 using 59 PHA bins.
Reduced chi-squared = 1.092842 for 57 degrees of freedom
Null hypothesis probability = 0.294
Photon flux (15-150 keV) in 33.10 sec: 4.943131E-02 ( -0.0203318 0.0204886 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.30747e-08 ( -4.00338e-08 4.71e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.098 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.49894 ( )
Epeak [keV] : 26.6518 ( -6.96334 8.43124 )
Norm@50keV : 0.786694 ( -1.68094 6.08975 )
------------------------------------------------------------
Chi-Squared = 59.41272 using 59 PHA bins.
Reduced chi-squared = 1.060941 for 56 degrees of freedom
Null hypothesis probability = 0.352
Photon flux (15-150 keV) in 33.10 sec: 4.892465E-02 ( -0.018518 0.0185155 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.81615e-08 ( -2.68537e-08 2.85315e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.098 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.64155 ( -8.35845 3.15955 )
beta : -9.21747 ( -0.782526 19.2175 )
Epeak [keV] : 13.3440 ( -13.2440 9986.66 )
Norm@50keV : 9.827297E-04 ( -9.75994 26.0025 )
------------------------------------------------------------
Chi-Squared = 61.41904 using 59 PHA bins.
Reduced chi-squared = 1.116710 for 55 degrees of freedom
Null hypothesis probability = 0.257
Photon flux (15-150 keV) in 33.10 sec: 4.958085E-02 ( -0.0193064 0.0193071 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.72488e-08 ( -3.183e-08 4.21297e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 33.098 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.50705 ( -0.762391 1.00403 )
Norm@50keV : 2.504377E-04 ( -2.504377E-04 1.747289E-04) )
------------------------------------------------------------
Chi-Squared = 62.29200 using 59 PHA bins.
Reduced chi-squared = 1.092842 for 57 degrees of freedom
Null hypothesis probability = 0.294
Photon flux (15-150 keV) in 33.10 sec: 4.943131E-02 ( -0.0203318 0.0204886 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.30747e-08 ( -4.00338e-08 4.71e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.098 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.49894 ( )
Epeak [keV] : 26.6518 ( -6.96334 8.43124 )
Norm@50keV : 0.786694 ( -1.68094 6.08975 )
------------------------------------------------------------
Chi-Squared = 59.41272 using 59 PHA bins.
Reduced chi-squared = 1.060941 for 56 degrees of freedom
Null hypothesis probability = 0.352
Photon flux (15-150 keV) in 33.10 sec: 4.892465E-02 ( -0.018518 0.0185155 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.81615e-08 ( -2.68537e-08 2.85315e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 33.098 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.64155 ( -8.35845 3.15955 )
beta : -9.21747 ( )
Epeak [keV] : 13.3440 ( )
Norm@50keV : 9.827297E-04 ( )
------------------------------------------------------------
Chi-Squared = 61.41904 using 59 PHA bins.
Reduced chi-squared = 1.116710 for 55 degrees of freedom
Null hypothesis probability = 0.257
Photon flux (15-150 keV) in 33.10 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Wed Jan 9 14:12:29 EST 2008