batgrbproduct Analysis for Trigger=731887
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 15 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time (local time): Wed Jan 11 16:53:27 EST 2017
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger731887/batgroup_hand_proc
======================================================================
Trigger: 00731887 Segment: 000
BAT Trigger Time: 505787626.624 [s; MET]
Trigger Stop: 505787630.72 [s; MET]
UTC: 2017-01-11T00:33:28.182060 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 20.7174783857572 Dec: -32.540066578583 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.62
Image Trigger?: NO
Rate S/N Ratio: 12.5299640861417 [ if not an image trigger ]
Image S/N Ratio: 8.62
Flight Position: [ source = BAT ]
RA: 20.7174783857572 Dec: -32.540066578583 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 20.6864648869253 Dec: -32.5430137370688 [deg; J2000]
{ 01h 22m 44.8s , -32d 32' 34.8" }
+/- 1.95001389359198 [arcmin] (estimated 90% radius based on SNR)
+/- 1.02304371761089 [arcmin] (formal 1-sigma fit error)
SNR: 11.7159848242223
Angular difference between Flight and Ground position is 1.578601 arcmin
Partial Coding Fraction: 0.4492188 [ including projection effects ]
Duration
T90: 33.4119999408722 +/- 14.4345220603801
Measured from: -12.3000000119209
to: 21.1119999289513 [s; relative to TRIGTIME]
T50: 10.7319999337196 +/- 3.0019966833292
Measured from: -5.41600000858307
to: 5.31599992513657 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 2.08399999141693
to: 3.08399999141693 [s; relative to TRIGTIME]
Total Fluence
Measured from: -13.5879999995232
to: 35.1559999585152 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.470843 0.496165 0.328647 0.081114
0.056300 0.056872 0.050789 0.046066 [error]
Peak 0.036880 0.035334 0.028466 0.004041
0.008356 0.009087 0.007698 0.006589 [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 1.35e-07 2.18e-07 2.64e-07 6.30e-07 7.97e-07 1.25e-06 erg/cm2
Error 2.55e-08 2.67e-08 5.02e-08 2.47e-07 1.17e-07 2.94e-07 erg/cm2
Peak flux Power-law 3.44e-01 3.12e-01 1.95e-01 1.86e-01 9.28e-01 1.04e+00 ph/cm2/s
Error 1.16e-01 7.08e-02 6.14e-02 1.14e-01 2.09e-01 2.38e-01 ph/cm2/s
Fluence Cutoff-PL 1.36e-07 2.18e-07 2.64e-07 6.18e-07 7.94e-07 1.15e-06 erg/cm2
Error 2.55e-08 2.66e-08 5.03e-08 3.97e-07 1.26e-07 4.13e-07 erg/cm2
Peak flux Cutoff-PL 3.28e-01 3.30e-01 2.00e-01 1.09e-01 9.21e-01 9.66e-01 ph/cm2/s
Error 1.28e-01 9.02e-02 6.79e-02 1.53e-01 2.10e-01 2.65e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band 3.30e-01 3.27e-01 2.00e-01 1.17e-01 9.20e-01 9.77e-01 ph/cm2/s
Error -------- -------- -------- -------- -------- -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.719 0.225 - - 1.77e-03 2.46e-04 70.660 57
CPL 1.664 0.774 262.0 0.0 1.90e-03 0.00e+00 70.690 56
The chi2 of BB fit is Chi-Squared Chi-Squared 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 1.678 0.382 - - 7.04e-03 1.75e-03 47.230 57
CPL 1.247 1.459 80.3 -0.1 1.22e-02 5.46e-02 46.940 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: 18.048000 sec.
T50 in the 50-300 keV band: 9.280000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 48.744 -13.588 35.156
T90 33.412 -12.300 21.112
T50 10.732 -5.416 5.316
Peak 1.000 2.084 3.084
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
20.6865 -32.5430 0.0163 30.1162 -112.4604 1.3509198 11.716 TRIG_00731887
Foreground time interval of the image:
-13.588 35.156 (delta_t = 48.744 [sec])
Background time interval of the image:
-239.624 -13.588 (delta_t = 226.036 [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 -13.588 sec. to 35.156 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.71936 ( -0.221584 0.227998 )
Norm@50keV : 1.76925E-03 ( -0.000249069 0.000243557 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.66 using 59 PHA bins.
# Reduced chi-squared = 1.240 for 57 degrees of freedom
# Null hypothesis probability = 1.055707e-01
Photon flux (15-150 keV) in 48.74 sec: 0.236588 ( -0.029071 0.0290859 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.9725e-07 ( -1.15991e-07 1.18454e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -13.588 sec. to 35.156 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.66385 ( -0.817053 0.731366 )
Epeak [keV] : 261.964 ( )
Norm@50keV : 1.90283E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.69 using 59 PHA bins.
# Reduced chi-squared = 1.262 for 56 degrees of freedom
# Null hypothesis probability = 8.937546e-02
Photon flux (15-150 keV) in 48.74 sec: 0.236607 ( -0.029147 0.028991 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.94462e-07 ( -1.325e-07 1.20066e-07 ) ergs/cm2
Band function
Time interval is from -13.588 sec. to 35.156 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.95427 ( -14.3445 -4.95427 )
beta : -1.87284 ( -0.302907 0.267764 )
Epeak [keV] : 23.4547 ( -7.12097 4.59521 )
Norm@50keV : 326.933 ( -39.6151 3235.21 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.65 using 59 PHA bins.
# Reduced chi-squared = 1.230 for 55 degrees of freedom
# Null hypothesis probability = 1.177183e-01
Photon flux (15-150 keV) in 48.74 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] : 10.7978 (-1.74092 2.15827)
R^2/D10^2 : 8.24413E-02 (-0.0402578 0.0763813)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 89.94 using 59 PHA bins.
# Reduced chi-squared = 1.578 for 57 degrees of freedom
# Null hypothesis probability = 3.521382e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.750e-08 2.315e-08
25- 50 2.691e-07 4.608e-08
50-150 1.747e-07 5.895e-08
15-150 5.414e-07 9.875e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 124.724 (-52.4626 -123.019)
Norm : 0.992603 (-0.144412 0.204967)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.51 using 59 PHA bins.
# Reduced chi-squared = 1.255 for 57 degrees of freedom
# Null hypothesis probability = 9.350041e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.258e-07 2.352e-08
25- 50 2.265e-07 7.433e-08
50-150 4.119e-07 2.412e-07
15-150 7.643e-07 3.109e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.98960 (-1.74516 2.17945)
R1^2/D10^2 : 0.336880 (-0.203209 0.590843)
kT2 [keV] : 36.0726 (-16.0713 -36.0805)
R2^2/D10^2 : 8.95554E-04 (-0.000870746 0.00339353)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.05 using 59 PHA bins.
# Reduced chi-squared = 1.237 for 55 degrees of freedom
# Null hypothesis probability = 1.112355e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.365e-07 4.518e-08
25- 50 2.277e-07 8.607e-08
50-150 4.640e-07 2.509e-07
15-150 8.283e-07 3.484e-07
Peak spectrum fit
Power-law model
Time interval is from 2.084 sec. to 3.084 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.67807 ( -0.370437 0.394341 )
Norm@50keV : 7.04279E-03 ( -0.00177886 0.00172248 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.23 using 59 PHA bins.
# Reduced chi-squared = 0.8286 for 57 degrees of freedom
# Null hypothesis probability = 8.184910e-01
Photon flux (15-150 keV) in 1 sec: 0.928309 ( -0.209208 0.209286 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.53247e-08 ( -1.69387e-08 1.73532e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.084 sec. to 3.084 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.24684 ( -1.73961 1.17917 )
Epeak [keV] : 80.2648 ( -80.1515 -80.2648 )
Norm@50keV : 1.21736E-02 ( -0.0121736 0.096969 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.94 using 59 PHA bins.
# Reduced chi-squared = 0.8382 for 56 degrees of freedom
# Null hypothesis probability = 8.005507e-01
Photon flux (15-150 keV) in 1 sec: 0.920543 ( -0.210265 0.210637 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.33464e-08 ( -1.79084e-08 1.83925e-08 ) ergs/cm2
Band function
Time interval is from 2.084 sec. to 3.084 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.26252 ( -1.02252 1.30697 )
beta : -9.37167 ( 9.37127 19.3713 )
Epeak [keV] : 83.1856 ( -49.1328 -83.1575 )
Norm@50keV : 1.18412E-02 ( -0.00607946 0.0120342 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.94 using 59 PHA bins.
# Reduced chi-squared = 0.8534 for 55 degrees of freedom
# Null hypothesis probability = 7.719716e-01
Photon flux (15-150 keV) in 1 sec: 0.920299 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 6.41621e-08 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 12.5855 (-3.52255 4.5505)
R^2/D10^2 : 0.195609 (-0.13136 0.437394)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.44 using 59 PHA bins.
# Reduced chi-squared = 0.9199 for 57 degrees of freedom
# Null hypothesis probability = 6.467005e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.570e-09 3.004e-09
25- 50 2.184e-08 8.338e-09
50-150 2.145e-08 1.247e-08
15-150 4.985e-08 1.972e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 139.152 (-78.8053 -136.826)
Norm : 3.88386 (-0.947879 1.37312)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.94 using 59 PHA bins.
# Reduced chi-squared = 0.8235 for 57 degrees of freedom
# Null hypothesis probability = 8.265327e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.003e-08 5.615e-09
25- 50 1.839e-08 1.040e-08
50-150 3.516e-08 2.243e-08
15-150 6.358e-08 3.840e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.04546 (-2.7567 4.45445)
R1^2/D10^2 : 1.87579 (-1.57291 17.766)
kT2 [keV] : 22.9353 (-10.1405 82.3543)
R2^2/D10^2 : 1.67209E-02 (-0.0163491 0.105701)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.26 using 59 PHA bins.
# Reduced chi-squared = 0.8411 for 55 degrees of freedom
# Null hypothesis probability = 7.932233e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.080e-08 6.500e-09
25- 50 1.798e-08 9.720e-09
50-150 3.486e-08 2.041e-08
15-150 6.364e-08 3.421e-08
Plot creation:
Wed Jan 11 17:58:19 EST 2017