batgrbproduct Analysis for Trigger=172516
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 19:38:26 EST 2008
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger172516/GCN5_download_hand
======================================================================
Trigger: 00172516 Segment: 000
BAT Trigger Time: 156150784 [s; MET]
Trigger Stop: 156150848 [s; MET]
UTC: 2005-12-13T07:13:04.106720 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 252.122941460355 Dec: -59.2071286962437 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.98
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 8.98
Flight Position: [ source = BAT ]
RA: 252.122941460355 Dec: -59.2071286962437 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 252.092441595541 Dec: -59.2280556693885 [deg; J2000]
{ 16h 48m 22.2s , -59d 13' 41.0" }
+/- 1.83844552445614 [arcmin] (estimated 90% radius based on SNR)
+/- 0.717315065428104 [arcmin] (formal 1-sigma fit error)
SNR: 12.7447573677545
RA = 16h 48m 22.2s (252.092442 deg.)
Dec = -59d 13' 41" (-59.228056 deg.)
Angular difference between Flight and Ground position is 1.566431 arcmin
Partial Coding Fraction: 0.6796875 [ including projection effects ]
Duration
T90: 71.0480000078678 +/- 4.98602527147389
Measured from: -8.43599998950958
to: 62.6120000183582 [s; relative to TRIGTIME]
T50: 53.3000000119209 +/- 4.99063000895054
Measured from: -1.67199999094009
to: 51.6280000209808 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 48.8840000033379
to: 49.8840000033379 [s; relative to TRIGTIME]
Total Fluence
Measured from: -10.7240000069141
to: 66.7159999907017 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.340683 0.571601 0.312484 0.051225
0.053765 0.052460 0.044977 0.037005 [error]
Peak 0.004951 0.027517 0.019905 0.009771
0.006100 0.006065 0.005231 0.004334 [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 1.21e-07 2.05e-07 2.66e-07 6.94e-07 7.82e-07 1.29e-06 erg/cm2
Error 2.23e-08 2.43e-08 4.30e-08 2.33e-07 1.03e-07 2.71e-07 erg/cm2
Peak flux Power-law 1.06e-01 1.45e-01 1.45e-01 2.63e-01 4.80e-01 6.58e-01 ph/cm2/s
Error 6.45e-02 5.40e-02 4.00e-02 1.66e-01 1.40e-01 1.85e-01 ph/cm2/s
Fluence Cutoff-PL 1.09e-07 2.27e-07 2.70e-07 2.08e-07 7.28e-07 8.10e-07 erg/cm2
Error 2.54e-08 3.35e-08 5.02e-08 2.77e-07 1.17e-07 2.10e-07 erg/cm2
Peak flux Cutoff-PL 9.66e-02 1.47e-01 1.51e-01 1.89e-01 4.74e-01 5.84e-01 ph/cm2/s
Error 7.51e-02 5.89e-02 5.15e-02 2.14e-01 1.43e-01 2.46e-01 ph/cm2/s
Fluence Band 1.08e-07 2.31e-07 2.56e-07 4.77e-07 7.49e-07 1.04e-06 erg/cm2
Error 2.54e-08 3.42e-08 4.46e-08 3.97e-07 1.13e-07 4.18e-07 erg/cm2
Peak flux Band 6.90e-02 1.61e-01 1.49e-01 2.23e-01 4.57e-01 6.04e-01 ph/cm2/s
Error 7.83e-02 4.51e-02 4.49e-02 1.95e-01 1.50e-01 2.07e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.628 0.199 - - 1.08e-03 1.34e-04 53.425 57
CPL 0.773 0.936 65.5 249.8 3.16e-03 5.75e-03 50.460 0
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 0.994 0.507 - - 4.17e-03 1.19e-03 51.445 57
CPL 0.561 3.454 193.5 5000.0 6.47e-03 5.24e-02 51.370 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: 0.064000 sec.
T50 in the 50-300 keV band: 0.064000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 77.440 -10.724 66.716
T90 71.048 -8.436 62.612
T50 53.300 -1.672 51.628
Peak 1.000 48.884 49.884
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
252.0924 -59.2281 0.0151 21.6 -85.3 1.1695 12.7 TRIG_00172516
------------------------------------------
Foreground time interval of the image:
-6.799 66.716 (delta_t = 73.515 [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 -10.724 sec. to 66.716 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.62847 ( -0.197715 0.200770 )
Norm@50keV : 1.083292E-03 ( -1.344523E-04 1.331028E-04) )
------------------------------------------------------------
Chi-Squared = 53.42503 using 59 PHA bins.
Reduced chi-squared = 0.9372811 for 57 degrees of freedom
Null hypothesis probability = 0.610
Photon flux (15-150 keV) in 77.44 sec: 0.140462 ( -0.016578 0.0166 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.82051e-07 ( -1.02773e-07 1.04048e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -10.724 sec. to 66.716 sec.
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.772773 ( -1.02922 0.842119 )
Epeak [keV] : 65.4646 ( -16.5871 482.967 )
Norm@50keV : 3.162719E-03 ( -3.162719E-03 8.339128E-03) )
------------------------------------------------------------
Chi-Squared = 50.45972 using 59 PHA bins.
but latest trial 1.61126 gives Chi-Squared = 2.64136
Reduced chi-squared = 0.9010664 for 56 degrees of freedom
Null hypothesis probability = 0.684
Photon flux (15-150 keV) in 77.44 sec: 0.136489 ( -0.017118 0.017095 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.27543e-07 ( -1.16067e-07 1.17986e-07 ) ergs/cm2
Band function
Time interval is from -10.724 sec. to 66.716 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.857800 ( -1.53415 4.32365 )
beta : -2.21550 ( -2.12583 0.384119 )
Epeak [keV] : 65.3026 ( -15.0370 47.6682 )
Norm@50keV : 2.907465E-03 ( -0.347281 18.1223 )
------------------------------------------------------------
Chi-Squared = 50.37790 using 59 PHA bins.
Reduced chi-squared = 0.9159617 for 55 degrees of freedom
Null hypothesis probability = 0.652
Photon flux (15-150 keV) in 77.44 sec: 0.137227 ( -0.016285 0.017167 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.49024e-07 ( -1.12562e-07 1.13835e-07 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 48.884 sec. to 49.884 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.994421 ( -0.541910 0.472928 )
Norm@50keV : 4.170548E-03 ( -1.213345E-03 1.164865E-03) )
------------------------------------------------------------
Chi-Squared = 51.44536 using 59 PHA bins.
Reduced chi-squared = 0.9025502 for 57 degrees of freedom
Null hypothesis probability = 0.683
Photon flux (15-150 keV) in 1.000 sec: 0.480240 ( -0.138791 0.14057 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.52276e-08 ( -1.24895e-08 1.24865e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 48.884 sec. to 49.884 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.561333 ( -2.93935 3.96955 )
Epeak [keV] : 193.541 ( -193.531 9806.46 )
Norm@50keV : 6.468295E-03 ( -6.468295E-03 9.834018E-02) )
------------------------------------------------------------
Chi-Squared = 51.37047 using 59 PHA bins.
Reduced chi-squared = 0.9173298 for 56 degrees of freedom
Null hypothesis probability = 0.650
Photon flux (15-150 keV) in 1.000 sec: 0.474382 ( -0.142614 0.143983 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.46454e-08 ( -1.36558e-08 1.28962e-08 ) ergs/cm2
Band function
Time interval is from 48.884 sec. to 49.884 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.193543 ( -14.6293 0.370691 )
beta : -1.11292 ( -1.12416 0.684673 )
Epeak [keV] : 96.4433 ( -41.8056 9958.09 )
Norm@50keV : 1.106709E-02 ( -9.69528 662811. )
------------------------------------------------------------
Chi-Squared = 51.21140 using 59 PHA bins.
Reduced chi-squared = 0.9311163 for 55 degrees of freedom
Null hypothesis probability = 0.620
Photon flux (15-150 keV) in 1.000 sec: 0.456924 ( -0.14176 0.157323 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.46328e-08 ( -1.36569e-08 1.28854e-08 ) ergs/cm2
Plot creation:
Wed Jan 9 19:48:19 EST 2008