batgrbproduct analysis for trigger=868851
batgrbproduct Analysis for Trigger=868851
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): Sat Oct 27 16:15:16 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger868851/GCN5_download_cron
======================================================================
Trigger: 00868851 Segment: 000
BAT Trigger Time: 562218640 [s; MET]
Trigger Stop: 562218704 [s; MET]
UTC: 2018-10-26T03:50:18.185300 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 244.794626082559 Dec: -16.0636294274481 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 26.21
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 26.21
Flight Position: [ source = BAT ]
RA: 244.794626082559 Dec: -16.0636294274481 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 244.803295082385 Dec: -16.0866716000422 [deg; J2000]
{ 16h 19m 12.8s , -16d 05' 12.0" }
+/- 1.02470791726461 [arcmin] (estimated 90% radius based on SNR)
+/- 0.469365488817438 [arcmin] (formal 1-sigma fit error)
SNR: 29.3748320212728
Angular difference between Flight and Ground position is 1.470099 arcmin
Partial Coding Fraction: 0.765625 [ including projection effects ]
Duration
T90: 346.611999869347 +/- 6.87028149940324
Measured from: -16.3079998493195
to: 330.304000020027 [s; relative to TRIGTIME]
T50: 203.363999962807 +/- 6.51453637075698
Measured from: 62.4280000925064
to: 265.792000055313 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 231.175999999046
to: 232.175999999046 [s; relative to TRIGTIME]
Total Fluence
Measured from: -64.7960000038147
to: 344.55999994278 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 43.740049 3.737382 -0.104241 0.023520
0.218980 0.173461 0.139586 0.119659 [error]
Peak 0.150116 0.041993 0.004565 0.010239
0.010930 0.008267 0.006530 0.005656 [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 1.64e-05 1.65e-06 6.73e-08 2.86e-09 1.81e-05 1.81e-05 erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Power-law 1.58e+00 3.48e-01 3.90e-02 4.83e-03 1.97e+00 1.97e+00 ph/cm2/s
Error 2.41e-01 8.88e-02 2.33e-02 5.14e-03 2.69e-01 2.69e-01 ph/cm2/s
Fluence Cutoff-PL 1.47e-05 1.39e-06 1.30e-09 3.52e-16 1.61e-05 1.61e-05 erg/cm2
Error 1.41e-06 1.21e-07 1.92e-09 1.44e-14 1.42e-06 1.42e-06 erg/cm2
Peak flux Cutoff-PL 1.58e+00 3.47e-01 3.40e-02 2.68e-03 1.96e+00 1.96e+00 ph/cm2/s
Error 2.43e-01 9.86e-02 3.32e-02 5.92e-03 2.03e-01 2.55e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band -------- -------- -------- -------- -------- -------- 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 6.612 0.000 - - 1.99e-04 0.00e+00 114.450 57
CPL 1.000 0.000 50.0 0.0 2.34e-03 0.00e+00 1210.450 56
The chi2 of BB fit is 64.50 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 4.158 0.523 - - 2.78e-03 1.32e-03 51.380 57
CPL 1.000 0.000 50.0 0.0 2.27e-02 0.00e+00 129.800 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 409.356 -64.796 344.560
T90 346.612 -16.308 330.304
T50 203.364 62.428 265.792
Peak 1.000 231.176 232.176
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
244.8033 -16.0867 0.0065 24.1 -46.7 16.0898 29.4 TRIG_00868851
------------------------------------------
Foreground time interval of the image:
-64.796 68.560 (delta_t = 133.356 [sec])
70.000 205.240 (delta_t = 135.240 [sec])
206.000 273.501 (delta_t = 67.501 [sec])
Background time interval of the image:
-239.000 -64.796 (delta_t = 174.204 [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
Multiple GTIs in the spectrum
tstart tstop
-64.796000 68.560000
70.000000 205.240000
206.000000 344.560000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 6.61158 ( )
Norm@50keV : 1.98531E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 114.45 using 59 PHA bins.
# Reduced chi-squared = 2.0078 for 57 degrees of freedom
# Null hypothesis probability = 9.896501e-06
Photon flux (15-150 keV) in 407.2 sec: 1.52027 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.81017e-05 ( 0 0 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-64.796000 68.560000
70.000000 205.240000
206.000000 344.560000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( )
Epeak [keV] : 50.0000 ( )
Norm@50keV : 2.34072E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 1210.45 using 59 PHA bins.
# Reduced chi-squared = 21.6152 for 56 degrees of freedom
# Null hypothesis probability = 1.772243e-216
Photon flux (15-150 keV) in 407.2 sec: 1.32741 ( -0.13025 0.12838 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.60517e-05 ( -1.42658e-06 1.40386e-06 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-64.796000 68.560000
70.000000 205.240000
206.000000 344.560000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.81461 ( )
beta : -6.63211 ( )
Epeak [keV] : 382.437 ( )
Norm@50keV : 2.65169E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 114.48 using 59 PHA bins.
# Reduced chi-squared = 2.0815 for 55 degrees of freedom
# Null hypothesis probability = 4.567153e-06
Photon flux (15-150 keV) in 407.2 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] : 2.67457 (-0.0911884 0.0978274)
R^2/D10^2 : 398.739 (-109.467 147.674)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.50 using 59 PHA bins.
# Reduced chi-squared = 1.132 for 57 degrees of freedom
# Null hypothesis probability = 2.308553e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.434e-05 1.450e-06
25- 50 1.375e-06 1.142e-07
50-150 8.229e-10 2.710e-10
15-150 1.572e-05 1.435e-06
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 4.43081 (-0.207813 0.228555)
Norm : 513.622 (-118.925 151.941)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.19 using 59 PHA bins.
# Reduced chi-squared = 1.179 for 57 degrees of freedom
# Null hypothesis probability = 1.673469e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.540e-05 1.509e-06
25- 50 1.461e-06 1.165e-07
50-150 3.967e-09 1.273e-09
15-150 1.686e-05 1.218e-06
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.67449 (-0.0973606 0.0923189)
R1^2/D10^2 : 398.842 (-101.898 155.648)
kT2 [keV] : 1.00000E-04 (-0.0001 -0.0001)
R2^2/D10^2 : 6.04935E-16 (-6.04935e-16 -6.04935e-16)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.52 using 59 PHA bins.
#Fit statistic : Chi-Squared = 64.50 using 59 PHA bins.
# Reduced chi-squared = 1.173 for 55 degrees of freedom
# Reduced chi-squared = 1.173 for 55 degrees of freedom
# Null hypothesis probability = 1.780997e-01
# Null hypothesis probability = 1.783990e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.430e-05 1.431e-06
25- 50 1.382e-06 1.224e-07
50-150 8.438e-10 3.085e-10
15-150 1.568e-05 1.450e-06
Peak spectrum fit
Power-law model
Time interval is from 231.176 sec. to 232.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 4.15844 ( -0.490008 0.555356 )
Norm@50keV : 2.77511E-03 ( -0.00115166 0.00148511 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.38 using 59 PHA bins.
# Reduced chi-squared = 0.9014 for 57 degrees of freedom
# Null hypothesis probability = 6.849927e-01
Photon flux (15-150 keV) in 1 sec: 1.96769 ( -0.269197 0.269206 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.87573e-08 ( -1.02775e-08 1.05705e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 231.176 sec. to 232.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( )
Epeak [keV] : 50.0000 ( )
Norm@50keV : 2.26750E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 129.80 using 59 PHA bins.
# Reduced chi-squared = 2.3178 for 56 degrees of freedom
# Null hypothesis probability = 8.600002e-08
Photon flux (15-150 keV) in 1 sec: 1.96081 ( -0.26851 0.13731 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.79147e-08 ( -1.1666e-08 1.12913e-08 ) ergs/cm2
Band function
Time interval is from 231.176 sec. to 232.176 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 3.76307 ( 1.66549 1.66549 )
beta : -4.29814 ( 4.38296 0.688946 )
Epeak [keV] : 12.6670 ( -2.71831 2.63167 )
Norm@50keV : 3.43176E+04 ( -34321.9 5.44695e+07 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.03 using 59 PHA bins.
# Reduced chi-squared = 0.9278 for 55 degrees of freedom
# Null hypothesis probability = 6.270310e-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] : 3.55337 (-0.4811 0.56994)
R^2/D10^2 : 96.2238 (-55.5825 138.203)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.26 using 59 PHA bins.
# Reduced chi-squared = 0.9694 for 57 degrees of freedom
# Null hypothesis probability = 5.407670e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.784e-08 1.670e-08
25- 50 1.215e-08 4.810e-09
50-150 6.910e-11 5.776e-11
15-150 6.007e-08 1.781e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 8.30532 (-1.84356 2.60651)
Norm : 100.353 (-46.4347 95.3964)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.59 using 59 PHA bins.
# Reduced chi-squared = 0.9227 for 57 degrees of freedom
# Null hypothesis probability = 6.409656e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.710e-08 1.109e-08
25- 50 1.551e-08 5.147e-09
50-150 6.166e-10 4.701e-10
15-150 6.323e-08 1.758e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.94334 (-1.34806 0.749115)
R1^2/D10^2 : 254.471 (-184.84 9984.03)
kT2 [keV] : 8.75683 (-7.17593 -8.77033)
R2^2/D10^2 : 0.366447 (-0.370253 2.64568)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.70 using 59 PHA bins.
# Reduced chi-squared = 0.9219 for 55 degrees of freedom
# Null hypothesis probability = 6.393372e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.761e-08 2.535e-08
25- 50 1.672e-08 8.870e-09
50-150 3.854e-09 3.040e-09
15-150 6.819e-08 3.521e-08
Plot creation:
Sat Oct 27 16:19:08 EDT 2018