batgrbproduct Analysis for Trigger=345945
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 v2.42
Process Start Time (local time): Tue Mar 10 10:11:18 EDT 2009
Host Name: gcn5
Current Working Dir: /local/data/raid2/prebascript/trigger345945/SDC
======================================================================
Trigger: 00345945 Segment: 000
BAT Trigger Time: 258334157.824 [s; MET]
Trigger Stop: 258334158.848 [s; MET]
UTC: 2009-03-09T23:29:13.262340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 284.980772926882 Dec: -25.2643001528138 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.07
Image Trigger?: NO
Rate S/N Ratio: 11.5758369027902 [ if not an image trigger ]
Image S/N Ratio: 7.07
Flight Position: [ source = BAT ]
RA: 284.980772926882 Dec: -25.2643001528138 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 284.975821408392 Dec: -25.2756740169076 [deg; J2000]
{ 18h 59m 54.2s , -25d 16' 32.4" }
+/- 2.314514534478 [arcmin] (estimated 90% radius based on SNR)
+/- 1.12726139197626 [arcmin] (formal 1-sigma fit error)
SNR: 9.17194332136815
Angular difference between Flight and Ground position is 0.733411 arcmin
Partial Coding Fraction: 0.6171875 [ including projection effects ]
Duration
T90: 3 +/- 1.4142135623731
Measured from: -0.824000000953674
to: 2.17599999904633 [s; relative to TRIGTIME]
T50: 1 +/- 1
Measured from: 0.175999999046326
to: 1.17599999904633 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.175999999046326
to: 1.17599999904633 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.824000000953674
to: 2.17599999904633 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.046018 0.073819 0.062785 0.033652
0.013520 0.012290 0.010886 0.009992 [error]
Peak 0.015616 0.047385 0.029175 0.018778
0.008052 0.007476 0.006506 0.005833 [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 1.60e-08 3.15e-08 4.83e-08 1.62e-07 1.35e-07 2.59e-07 erg/cm2
Error 5.18e-09 6.01e-09 1.07e-08 8.21e-08 2.61e-08 8.87e-08 erg/cm2
Peak flux Power-law 2.95e-01 2.97e-01 2.10e-01 2.35e-01 8.95e-01 1.04e+00 ph/cm2/s
Error 1.02e-01 6.38e-02 5.32e-02 1.24e-01 1.83e-01 2.09e-01 ph/cm2/s
Fluence Cutoff-PL 1.59e-08 3.15e-08 4.83e-08 1.60e-07 1.35e-07 2.24e-07 erg/cm2
Error 5.18e-09 6.02e-09 1.07e-08 8.14e-08 2.61e-08 1.19e-07 erg/cm2
Peak flux Cutoff-PL 2.17e-01 3.44e-01 2.16e-01 4.09e-02 8.12e-01 8.20e-01 ph/cm2/s
Error 1.36e-01 9.40e-02 6.88e-02 1.62e-01 2.17e-01 2.91e-01 ph/cm2/s
Fluence Band 1.55e-08 3.18e-08 4.81e-08 1.56e-07 1.34e-07 2.49e-07 erg/cm2
Error 4.29e-09 7.44e-09 1.09e-08 1.29e-07 2.49e-08 9.61e-08 erg/cm2
Peak flux Band 2.05e-01 3.50e-01 2.13e-01 9.47e-02 8.18e-01 8.60e-01 ph/cm2/s
Error 1.14e-01 7.65e-02 5.31e-02 9.49e-02 1.83e-01 2.23e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.383 0.323 - - 4.65e-03 8.06e-04 31.256 57
CPL 1.318 0.000 499.6 5000.0 4.95e-03 8.71e-03 31.326 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.502 0.353 - - 7.16e-03 1.46e-03 62.254 57
CPL -0.332 2.371 58.9 4977.8 6.55e-02 5.23e-01 60.836 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: 2.304000 sec.
T50 in the 50-300 keV band: 0.704000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 3.000 -0.824 2.176
T90 3.000 -0.824 2.176
T50 1.000 0.176 1.176
Peak 1.000 0.176 1.176
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
284.9758 -25.2757 0.0212 24.7 -93.0 0.2256 9.2 TRIG_00345945
------------------------------------------
Foreground time interval of the image:
-0.824 2.176 (delta_t = 3.000 [sec])
Background time interval of the image:
-60.824 -0.824 (delta_t = 60.000 [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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from -0.824 sec. to 2.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38267 ( -0.325247 0.321691 )
Norm@50keV : 4.645111E-03 ( -8.076327E-04 8.037700E-04) )
------------------------------------------------------------
Chi-Squared = 31.25581 using 59 PHA bins.
Reduced chi-squared = 0.5483476 for 57 degrees of freedom
Null hypothesis probability = 0.998
Photon flux (15-150 keV) in 3.000 sec: 0.563507 ( -0.100596 0.101236 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.35136e-07 ( -2.58621e-08 2.62905e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.824 sec. to 2.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.31799 ( )
Epeak [keV] : 499.569 ( -146.253 9853.74 )
Norm@50keV : 4.951682E-03 ( -1.231304E-03 1.618789E-02) )
------------------------------------------------------------
Chi-Squared = 31.32630 using 59 PHA bins.
Reduced chi-squared = 0.5593981 for 56 degrees of freedom
Null hypothesis probability = 0.997
Photon flux (15-150 keV) in 3.000 sec: 0.563291 ( -0.100558 0.101199 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.35132e-07 ( -2.58531e-08 2.63133e-08 ) ergs/cm2
Band function
Time interval is from -0.824 sec. to 2.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.960503 ( -9.03950 4.17949 )
beta : -1.43702 ( -8.56298 0.380103 )
Epeak [keV] : 89.7952 ( -89.6952 9892.77 )
Norm@50keV : 8.349413E-03 ( -8.349413E-03 0.242145 )
------------------------------------------------------------
Chi-Squared = 31.25533 using 59 PHA bins.
Reduced chi-squared = 0.5682787 for 55 degrees of freedom
Null hypothesis probability = 0.996
Photon flux (15-150 keV) in 3.000 sec: 0.560930 ( -0.107418 0.111165 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.34348e-07 ( -2.47497e-08 2.51502e-08 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.176 sec. to 1.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.50188 ( -0.351800 0.354773 )
Norm@50keV : 7.164343E-03 ( -1.470945E-03 1.454103E-03) )
------------------------------------------------------------
Chi-Squared = 62.25362 using 59 PHA bins.
Reduced chi-squared = 1.092169 for 57 degrees of freedom
Null hypothesis probability = 0.295
Photon flux (15-150 keV) in 1.000 sec: 0.894844 ( -0.182111 0.182926 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.79601e-08 ( -1.4998e-08 1.5325e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.176 sec. to 1.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.331686 ( -2.66831 2.07417 )
Epeak [keV] : 58.8683 ( -14.4877 9941.13 )
Norm@50keV : 6.552024E-02 ( -6.552024E-02 0.980734 )
------------------------------------------------------------
Chi-Squared = 60.83581 using 59 PHA bins.
Reduced chi-squared = 1.086354 for 56 degrees of freedom
Null hypothesis probability = 0.306
Photon flux (15-150 keV) in 1.000 sec: 0.811807 ( -0.213645 0.219493 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.67769e-08 ( -1.65241e-08 2.1588e-08 ) ergs/cm2
Band function
Time interval is from 0.176 sec. to 1.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.537887 ( -10.5379 4.11979 )
beta : -2.50400 ( -7.49600 1.10526 )
Epeak [keV] : 56.0975 ( -55.9975 9943.90 )
Norm@50keV : 8.670297E-02 ( -7.710013E-02 24.4546 )
------------------------------------------------------------
Chi-Squared = 59.90295 using 59 PHA bins.
Reduced chi-squared = 1.089145 for 55 degrees of freedom
Null hypothesis probability = 0.302
Photon flux (15-150 keV) in 1.000 sec: 0.818281 ( -0.185357 0.179898 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.90623e-08 ( -1.64352e-08 1.67979e-08 ) ergs/cm2
Plot creation:
Tue Mar 10 11:22:28 EDT 2009