batgrbproduct Analysis for Trigger=361831
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 v2.45
Process Start Time (local time): Mon Sep 7 10:34:43 EDT 2009
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger361831/SDC
======================================================================
Trigger: 00361831 Segment: 000
BAT Trigger Time: 273720263.168 [s; MET]
Trigger Stop: 273720267.264 [s; MET]
UTC: 2009-09-04T01:24:18.112980 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 264.191456096339 Dec: -25.2122851571245 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.98
Image Trigger?: NO
Rate S/N Ratio: 16.7332005306815 [ if not an image trigger ]
Image S/N Ratio: 7.98
Flight Position: [ source = BAT ]
RA: 264.191456096339 Dec: -25.2122851571245 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 264.193564814367 Dec: -25.2155784165271 [deg; J2000]
{ 17h 36m 46.5s , -25d 12' 56.1" }
+/- 1.23086590109822 [arcmin] (estimated 90% radius based on SNR)
+/- 0.476100405465506 [arcmin] (formal 1-sigma fit error)
SNR: 22.6071540417896
Angular difference between Flight and Ground position is 0.228357 arcmin
Partial Coding Fraction: 0.08886719 [ including projection effects ]
Duration
T90: 64 +/- 16
Measured from: -15.1679999828339
to: 48.8320000171661 [s; relative to TRIGTIME]
T50: 32 +/- 16
Measured from: 0.832000017166138
to: 32.8320000171661 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 8.33200001716614
to: 9.33200001716614 [s; relative to TRIGTIME]
Total Fluence
Measured from: -15.1679999828339
to: 64.8320000171661 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 4.594385 6.382555 5.093929 1.760963
0.238829 0.232768 0.210293 0.187847 [error]
Peak 1.334668 2.192807 1.627650 0.667192
0.110706 0.112111 0.101308 0.086635 [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 1.89e-06 3.22e-06 4.17e-06 1.09e-05 1.23e-05 2.02e-05 erg/cm2
Error 1.52e-07 1.50e-07 2.18e-07 1.28e-06 5.30e-07 1.41e-06 erg/cm2
Peak flux Power-law 1.22e+00 1.15e+00 7.52e-01 7.65e-01 3.43e+00 3.88e+00 ph/cm2/s
Error 1.34e-01 7.65e-02 5.43e-02 1.15e-01 2.20e-01 2.29e-01 ph/cm2/s
Fluence Cutoff-PL 1.89e-06 3.22e-06 4.18e-06 1.09e-05 1.23e-05 2.01e-05 erg/cm2
Error 1.52e-07 1.51e-07 2.18e-07 1.27e-06 5.30e-07 1.40e-06 erg/cm2
Peak flux Cutoff-PL 1.16e+00 1.17e+00 7.69e-01 6.08e-01 3.39e+00 3.70e+00 ph/cm2/s
Error 1.67e-01 6.43e-02 6.33e-02 2.72e-01 2.29e-01 3.48e-01 ph/cm2/s
Fluence Band 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 erg/cm2
Error 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.00e+00 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 1.626 0.078 - - 1.65e-02 6.83e-04 44.270 57
CPL 1.628 0.078 9999.4 0.0 1.65e-02 2.53e-03 44.290 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.609 0.105 - - 2.66e-02 1.58e-03 44.230 57
CPL 1.390 0.360 147.2 0.0 3.40e-02 0.00e+00 43.420 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: 52.736000 sec.
T50 in the 50-300 keV band: 31.680000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 80.000 -15.168 64.832
T90 64.000 -15.168 48.832
T50 32.000 0.832 32.832
Peak 1.000 8.332 9.332
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
264.1936 -25.2156 0.0085 52.6 166.9 17.5037 22.6 TRIG_00361831
------------------------------------------
Foreground time interval of the image:
-15.168 50.733 (delta_t = 65.901 [sec])
Background time interval of the image:
-56.467 -15.168 (delta_t = 41.299 [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 -15.168 sec. to 64.832 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.62565 ( -0.0775055 0.0776991 )
Norm@50keV : 1.64634E-02 ( -0.000682957 0.000682499 )
------------------------------------------------------------
# Chi-Squared = 44.27 using 59 PHA bins.
# Reduced chi-squared = 0.7766 for 57 degrees of freedom
# Null hypothesis probability = 8.908779e-01
Photon flux (15-150 keV) in 80 sec: 2.13277 ( -0.0985092 0.0989457 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22807e-05 ( -5.29098e-07 5.30202e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.168 sec. to 64.832 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.62769 ( -0.0806486 0.0756201 )
Epeak [keV] : 9999.36 ( -10000 -10000 )
Norm@50keV : 1.64739E-02 ( -0.000675067 0.00438271 )
------------------------------------------------------------
# Chi-Squared = 44.29 using 59 PHA bins.
# Reduced chi-squared = 0.7909 for 56 degrees of freedom
# Null hypothesis probability = 8.708552e-01
Photon flux (15-150 keV) in 80 sec: 2.13167 ( -0.09846 0.0989 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22827e-05 ( -5.2928e-07 5.304e-07 ) ergs/cm2
Band function
Time interval is from -15.168 sec. to 64.832 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.464806 ( 1.09867 1.09867 )
beta : -1.63776 ( 1.6394 0.0873053 )
Epeak [keV] : 26.2471 ( -38.3501 373.032 )
Norm@50keV : 0.732124 ( -0.732123 1968.74 )
------------------------------------------------------------
# Chi-Squared = 43.94 using 59 PHA bins.
# Reduced chi-squared = 0.7990 for 55 degrees of freedom
# Null hypothesis probability = 8.576130e-01
Photon flux (15-150 keV) in 80 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Peak spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.832 sec. to 16.832 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.60893 ( -0.10445 0.105037 )
Norm@50keV : 2.66141E-02 ( -0.00158582 0.00158294 )
------------------------------------------------------------
# Chi-Squared = 44.23 using 59 PHA bins.
# Reduced chi-squared = 0.7760 for 57 degrees of freedom
# Null hypothesis probability = 8.916071e-01
Photon flux (15-150 keV) in 16 sec: 3.42957 ( -0.219198 0.220013 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.97813e-06 ( -2.47674e-07 2.48234e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.832 sec. to 16.832 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.38993 ( -0.446768 0.273487 )
Epeak [keV] : 147.184 ( )
Norm@50keV : 3.39581E-02 ( )
------------------------------------------------------------
# Chi-Squared = 43.42 using 59 PHA bins.
# Reduced chi-squared = 0.7754 for 56 degrees of freedom
# Null hypothesis probability = 8.900824e-01
Photon flux (15-150 keV) in 16 sec: 3.38911 ( -0.229 0.22925 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.93274e-06 ( -2.65536e-07 1.99184e-07 ) ergs/cm2
Band function
Time interval is from 0.832 sec. to 16.832 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.581719 ( 0.875509 0.875509 )
beta : -1.73478 ( 1.74144 0.185355 )
Epeak [keV] : 51.6949 ( -52.5552 260.229 )
Norm@50keV : 0.107628 ( -0.0732444 1053.64 )
------------------------------------------------------------
# Chi-Squared = 42.00 using 59 PHA bins.
# Reduced chi-squared = 0.7636 for 55 degrees of freedom
# Null hypothesis probability = 9.011766e-01
Photon flux (15-150 keV) in 16 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Plot creation:
Mon Sep 7 12:00:45 EDT 2009