batgrbproduct Analysis for Trigger=515375
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 batgrbproduct analysis is using the flight position for the mask-weighting calculation.
- 4) This page will be updated for up to 10 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time (local time): Mon Feb 20 03:38:42 EST 2012
Host Name: gcn5
Current Working Dir: /local/data/raid16/prebascript_archive/trigger515375/GCN5_download_cron
======================================================================
Trigger: 00515375 Segment: 000
BAT Trigger Time: 351354616 [s; MET]
Trigger Stop: 351354680 [s; MET]
UTC: 2012-02-19T14:30:08.092340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 129.792968291079 Dec: 51.0246599454996 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.92
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 8.92
Flight Position: [ source = BAT ]
RA: 129.792968291079 Dec: 51.0246599454996 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 129.861689754795 Dec: 51.0061653619813 [deg; J2000]
{ 08h 39m 26.8s , +51d 00' 22.2" }
+/- 2.24025598628151 [arcmin] (estimated 90% radius based on SNR)
+/- 1.16052172616541 [arcmin] (formal 1-sigma fit error)
SNR: 9.60933138714943
Angular difference between Flight and Ground position is 2.821392 arcmin
Partial Coding Fraction: 0.7734375 [ including projection effects ]
Duration
T90: 90.4559999704361 +/- 10.8813793587216
Measured from: -6.01199990510941
to: 84.4440000653267 [s; relative to TRIGTIME]
T50: 61.0639999508858 +/- 10.1761754863075
Measured from: 2.34400010108948
to: 63.4080000519753 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -2.2960000038147
to: -1.2960000038147 [s; relative to TRIGTIME]
Total Fluence
Measured from: -7.83200001716614
to: 90.0600000023842 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.327323 0.495714 0.233213 0.081600
0.051231 0.052856 0.047144 0.041993 [error]
Peak 0.007598 0.016130 0.013608 0.007791
0.005260 0.005529 0.004790 0.004302 [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 9.43e-08 1.67e-07 2.27e-07 6.35e-07 6.57e-07 1.12e-06 erg/cm2
Error 1.97e-08 2.35e-08 4.40e-08 2.49e-07 1.07e-07 2.91e-07 erg/cm2
Peak flux Power-law 9.50e-02 1.03e-01 7.92e-02 9.97e-02 3.15e-01 3.77e-01 ph/cm2/s
Error 5.97e-02 4.32e-02 3.75e-02 1.12e-01 1.25e-01 1.54e-01 ph/cm2/s
Fluence Cutoff-PL 7.55e-08 2.12e-07 2.08e-07 4.62e-08 5.42e-07 0.00e+00 erg/cm2
Error 2.37e-08 3.67e-08 6.26e-08 9.55e-08 1.42e-07 0.00e+00 erg/cm2
Peak flux Cutoff-PL 4.43e-02 1.37e-01 8.48e-02 4.72e-03 2.71e-01 2.71e-01 ph/cm2/s
Error 6.35e-02 6.61e-02 6.87e-02 5.43e-02 1.27e-01 1.30e-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 2.88e-01 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 1.559 0.226 - - 7.14e-04 1.07e-04 63.870 57
CPL -0.603 1.691 51.6 14.1 1.16e-02 8.20e-02 54.790 56
The chi2 of BB fit is 55.53 which shows a significant improvement in the fit over a PL.
Check the BB fit.
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.377 0.644 - - 2.60e-03 1.04e-03 44.330 57
CPL -2.341 0.717 55.0 4962.0 2.10e-01 1.56e+03 41.610 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: 15.168000 sec.
T50 in the 50-300 keV band: 8.448000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 97.892 -7.832 90.060
T90 90.456 -6.012 84.444
T50 61.064 2.344 63.408
Peak 1.000 -2.296 -1.296
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
129.8617 +51.0062 0.0200 20.2 130.8 1.0337 9.6 TRIG_00515375
------------------------------------------
Foreground time interval of the image:
-7.832 70.901 (delta_t = 78.733 [sec])
Background time interval of the image:
-239.000 -212.100 (delta_t = 26.900 [sec])
-211.000 -7.832 (delta_t = 203.168 [sec])
Lightcurves
Notes:
- 1) All plots contain as much data as has been downloaded to date.
- 2) The mask-weighted light curves are using the flight position.
- 3) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 4) 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.
- 5) 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.
- 6) 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 -7.832 sec. to 90.060 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.55939 ( -0.223454 0.227908 )
Norm@50keV : 7.13645E-04 ( -0.000107234 0.000106114 )
------------------------------------------------------------
# Chi-Squared = 63.87 using 59 PHA bins.
# Reduced chi-squared = 1.121 for 57 degrees of freedom
# Null hypothesis probability = 2.478461e-01
Photon flux (15-150 keV) in 97.89 sec: 9.05903E-02 ( -0.0126448 0.0126498 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.56814e-07 ( -1.05845e-07 1.08327e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -7.832 sec. to 90.060 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.602634 ( -2.02103 1.36004 )
Epeak [keV] : 51.5662 ( -8.50313 19.765 )
Norm@50keV : 1.16294E-02 ( -0.0121831 0.151754 )
------------------------------------------------------------
# Chi-Squared = 54.79 using 59 PHA bins.
# Reduced chi-squared = 0.9783 for 56 degrees of freedom
# Null hypothesis probability = 5.209051e-01
Photon flux (15-150 keV) in 97.89 sec: 8.40364E-02 ( -0.0131 0.0131762 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.41754e-07 ( -1.08586e-07 1.75529e-07 ) ergs/cm2
Band function
Time interval is from -7.832 sec. to 90.060 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.46309 ( -2.50205 -1.99153 )
beta : -2.80089 ( -6.35555 0.940579 )
Epeak [keV] : 46.2059 ( -14.5516 20.7466 )
Norm@50keV : 3.94481E-02 ( -0.0352716 6.81859 )
------------------------------------------------------------
# Chi-Squared = 53.62 using 59 PHA bins.
# Reduced chi-squared = 0.9749 for 55 degrees of freedom
# Null hypothesis probability = 5.274086e-01
Photon flux (15-150 keV) in 97.89 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 12.4201 (-1.60771 1.93438)
R^2/D10^2 : 2.10911E-02 (-0.00867324 0.0138286)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
# Chi-Squared = 55.53 using 59 PHA bins.
# Reduced chi-squared = 0.9743 for 57 degrees of freedom
# Null hypothesis probability = 5.302882e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.750e-08 1.785e-08
25- 50 2.211e-07 4.155e-08
50-150 2.097e-07 6.275e-08
15-150 4.982e-07 9.593e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 154.817 ( )
Norm : 0.379674 (-0.0550787 0.0681056)
------------------------------------------------------------
# Chi-Squared = 60.74 using 59 PHA bins.
# Reduced chi-squared = 1.066 for 57 degrees of freedom
# Null hypothesis probability = 3.425586e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.107e-08 5.012e-08
25- 50 1.748e-07 9.593e-08
50-150 3.809e-07 2.110e-07
15-150 6.467e-07 3.523e-07
Double BB
------------------------------------------------------------
# Chi-Squared = 53.88 using 59 PHA bins.
# Chi-Squared = 53.85 using 59 PHA bins.
# Chi-Squared = 53.80 using 59 PHA bins.
# Chi-Squared = 53.77 using 59 PHA bins.
# Reduced chi-squared = 0.9796 for 55 degrees of freedom
# Reduced chi-squared = 0.9790 for 55 degrees of freedom
# Reduced chi-squared = 0.9782 for 55 degrees of freedom
# Reduced chi-squared = 0.9776 for 55 degrees of freedom
# Null hypothesis probability = 5.174766e-01
# Null hypothesis probability = 5.187958e-01
# Null hypothesis probability = 5.204321e-01
# Null hypothesis probability = 5.217779e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.480e-08 4.262e-08
25- 50 2.152e-07 1.375e-07
50-150 2.850e-07 1.763e-07
15-150 5.750e-07 3.279e-07
Peak spectrum fit
Power-law model
Time interval is from -2.296 sec. to -1.296 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.37712 ( -0.64133 0.647383 )
Norm@50keV : 2.59603E-03 ( -0.00104327 0.00103297 )
------------------------------------------------------------
# Chi-Squared = 44.33 using 59 PHA bins.
# Reduced chi-squared = 0.7777 for 57 degrees of freedom
# Null hypothesis probability = 8.896379e-01
Photon flux (15-150 keV) in 1 sec: 0.314566 ( -0.124547 0.125194 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.52005e-08 ( -1.07903e-08 1.12758e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.296 sec. to -1.296 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.34120 ( 2.41717 3.85026 )
Epeak [keV] : 55.0126 ( -14.9534 9909.03 )
Norm@50keV : 0.210160 ( -0.266371 3112.21 )
------------------------------------------------------------
# Chi-Squared = 41.61 using 59 PHA bins.
# Reduced chi-squared = 0.7430 for 56 degrees of freedom
# Null hypothesis probability = 9.241197e-01
Photon flux (15-150 keV) in 1 sec: 0.270505 ( -0.118701 0.13442 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.93189e-08 ( -8.9137e-09 2.90272e-08 ) ergs/cm2
Band function
Time interval is from -2.296 sec. to -1.296 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 3.16700 ( -1.15736 4.69166 )
beta : -10.00000 ( 1.02488e+12 1.02488e+12 )
Epeak [keV] : 53.0090 ( -15.7402 -55.9778 )
Norm@50keV : 0.555922 ( -0.484559 2.9022 )
------------------------------------------------------------
# Chi-Squared = 41.58 using 59 PHA bins.
# Reduced chi-squared = 0.7560 for 55 degrees of freedom
# Null hypothesis probability = 9.092724e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 14.6579 (-4.29735 7.18844)
R^2/D10^2 : 4.37921E-02 (-0.043792 0.103417)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
# Chi-Squared = 41.75 using 59 PHA bins.
# Reduced chi-squared = 0.7325 for 57 degrees of freedom
# Null hypothesis probability = 9.352519e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.977e-09 1.256e-09
25- 50 7.687e-09 4.707e-09
50-150 1.112e-08 7.875e-09
15-150 2.079e-08 1.334e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 (-200 -200)
Norm : 1.31099 (-0.510599 0.58708)
------------------------------------------------------------
# Chi-Squared = 44.03 using 59 PHA bins.
# Reduced chi-squared = 0.7725 for 57 degrees of freedom
# Null hypothesis probability = 8.957141e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.265e-09 2.050e-09
25- 50 6.280e-09 4.012e-09
50-150 1.377e-08 8.435e-09
15-150 2.332e-08 1.416e-08
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 1.81166 ( )
R1^2/D10^2 : 67.1763 (-77.7979 -77.7979)
kT2 [keV] : 14.9017 (-4.49289 7.93766)
R2^2/D10^2 : 4.08817E-02 (-0.0409344 0.104096)
------------------------------------------------------------
# Chi-Squared = 41.75 using 59 PHA bins.
# Chi-Squared = 41.68 using 59 PHA bins.
# Reduced chi-squared = 0.7591 for 55 degrees of freedom
# Reduced chi-squared = 0.7579 for 55 degrees of freedom
# Null hypothesis probability = 9.060594e-01
# Null hypothesis probability = 9.073677e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 0.000e+00 0.000e+00
25- 50 0.000e+00 0.000e+00
50-150 0.000e+00 0.000e+00
15-150 0.000e+00 0.000e+00
Plot creation:
Mon Feb 20 04:16:12 EST 2012