batgrbproduct analysis for trigger=840853
batgrbproduct Analysis for Trigger=840853
Analysis Summary
Special note:
- This trigger occurred when BAT was in the
process of resuming to normal operation from the recent reboot.
The LLD for some detectors was set to higher energy levels.
Therefore, the spectral fits here use only energy channels from 22 keV to 150 keV.
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 Jun 13 19:40:30 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger840853/GCN5_download_cron
======================================================================
Trigger: 00840853 Segment: 000
BAT Trigger Time: 550597000 [s; MET]
Trigger Stop: 550597080 [s; MET]
UTC: 2018-06-13T15:36:18.900460 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 211.562192886621 Dec: -43.0756203733291 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.59
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 10.59
Flight Position: [ source = BAT ]
RA: 211.562192886621 Dec: -43.0756203733291 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 211.543917497897 Dec: -43.0645738270669 [deg; J2000]
{ 14h 06m 10.5s , -43d 03' 52.5" }
+/- 1.96666109266687 [arcmin] (estimated 90% radius based on SNR)
+/- 0.930876823575038 [arcmin] (formal 1-sigma fit error)
SNR: 11.574567484212
Angular difference between Flight and Ground position is 1.039685 arcmin
Partial Coding Fraction: 0.96875 [ including projection effects ]
Duration
T90: 51.3600001335144 +/- 9.14108445629786
Measured from: 27.9120000600815
to: 79.2720001935959 [s; relative to TRIGTIME]
T50: 24.0800000429153 +/- 9.47427007997982
Measured from: 37.5920001268387
to: 61.672000169754 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 42.9880000352859
to: 43.9880000352859 [s; relative to TRIGTIME]
Total Fluence
Measured from: 24.8400000333786
to: 82.7280000448227 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.340545 0.491443 0.213493 0.043966
0.043857 0.046821 0.042193 0.042132 [error]
Peak 0.018336 0.015603 0.011941 0.006142
0.005802 0.006276 0.005606 0.005665 [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 9.33e-08 1.62e-07 2.15e-07 5.82e-07 6.27e-07 1.05e-06 erg/cm2
Error 1.64e-08 2.00e-08 3.94e-08 2.11e-07 9.52e-08 2.52e-07 erg/cm2
Peak flux Power-law 1.24e-01 1.15e-01 7.36e-02 7.28e-02 3.42e-01 3.85e-01 ph/cm2/s
Error 6.72e-02 4.62e-02 4.26e-02 9.24e-02 1.38e-01 1.65e-01 ph/cm2/s
Fluence Cutoff-PL 8.58e-08 2.08e-07 1.63e-07 2.54e-08 4.80e-07 4.82e-07 erg/cm2
Error 1.85e-08 3.42e-08 6.46e-08 7.26e-08 1.01e-07 1.23e-07 erg/cm2
Peak flux Cutoff-PL 1.14e-01 1.61e-01 4.78e-02 1.36e-03 3.24e-01 3.24e-01 ph/cm2/s
Error 7.53e-02 7.82e-02 5.72e-02 5.57e-02 1.32e-01 1.49e-01 ph/cm2/s
Fluence Band 8.90e-08 2.07e-07 1.78e-07 2.53e-07 5.67e-07 7.29e-07 erg/cm2
Error 1.90e-08 3.10e-08 4.35e-08 -------- 9.77e-08 -------- 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 1.593 0.202 - - 1.16e-03 1.61e-04 74.150 57
CPL -0.546 1.608 44.9 12.6 2.40e-02 1.80e-01 65.820 56
The chi2 of BB fit is 67.18 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 1.638 0.680 - - 2.63e-03 1.22e-03 55.270 57
CPL -1.064 1.048 40.8 0.0 1.38e-01 0.00e+00 53.710 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 57.888 24.840 82.728
T90 51.360 27.912 79.272
T50 24.080 37.592 61.672
Peak 1.000 42.988 43.988
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
211.5439 -43.0646 0.0167 17.9 165.9 1.1083 11.6 TRIG_00840853
------------------------------------------
Foreground time interval of the image:
24.840 82.728 (delta_t = 57.888 [sec])
Background time interval of the image:
-239.000 24.840 (delta_t = 263.840 [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 24.840 sec. to 82.728 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.59283 ( -0.200022 0.20384 )
Norm@50keV : 1.15748E-03 ( -0.000161922 0.000159772 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 74.15 using 59 PHA bins.
# Reduced chi-squared = 1.301 for 57 degrees of freedom
# Null hypothesis probability = 6.308187e-02
Photon flux (15-150 keV) in 57.89 sec: 0.148413 ( -0.0183396 0.01834 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.27215e-07 ( -9.38918e-08 9.64691e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 24.840 sec. to 82.728 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.545672 ( -1.84874 1.36719 )
Epeak [keV] : 44.9075 ( -7.23699 17.9904 )
Norm@50keV : 2.40329E-02 ( -0.0242175 0.335254 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.82 using 59 PHA bins.
# Reduced chi-squared = 1.175 for 56 degrees of freedom
# Null hypothesis probability = 1.735090e-01
Photon flux (15-150 keV) in 57.89 sec: 0.139180 ( -0.018274 0.018635 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.80312e-07 ( -8.74185e-08 1.1456e-07 ) ergs/cm2
Band function
Time interval is from 24.840 sec. to 82.728 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.98349 ( -3.3463 -4.98349 )
beta : -2.23543 ( -0.575996 0.364686 )
Epeak [keV] : 30.2676 ( -3.95157 3.6685 )
Norm@50keV : 48.7795 ( -5.77749 68.1413 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.49 using 59 PHA bins.
# Reduced chi-squared = 1.064 for 55 degrees of freedom
# Null hypothesis probability = 3.483787e-01
Photon flux (15-150 keV) in 57.89 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 5.67222e-07 ( -5.66817e-07 -9.45934e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 10.7101 (-1.26267 1.49541)
R^2/D10^2 : 5.85348E-02 (-0.0225378 0.0345225)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.18 using 59 PHA bins.
# Reduced chi-squared = 1.179 for 57 degrees of freedom
# Null hypothesis probability = 1.676481e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.074e-08 1.734e-08
25- 50 2.205e-07 3.580e-08
50-150 1.399e-07 4.067e-08
15-150 4.411e-07 7.343e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 135.143 (-55.4392 -133.118)
Norm : 0.625876 (-0.0800363 0.106966)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.06 using 59 PHA bins.
# Reduced chi-squared = 1.247 for 57 degrees of freedom
# Null hypothesis probability = 9.974771e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.379e-08 2.641e-08
25- 50 1.711e-07 7.437e-08
50-150 3.229e-07 2.021e-07
15-150 5.878e-07 2.670e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.52265 (-1.18818 1.3725)
R1^2/D10^2 : 8.29309E-02 (-0.0384087 0.0241731)
kT2 [keV] : 199.363 (-199.363 -199.363)
R2^2/D10^2 : 1.40417E-05 (-7.0558e-06 0.000616776)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.72 using 59 PHA bins.
# Reduced chi-squared = 1.068 for 55 degrees of freedom
# Null hypothesis probability = 3.406662e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.807e-08 2.517e-08
25- 50 2.104e-07 5.879e-08
50-150 3.064e-07 7.950e-08
15-150 6.049e-07 1.608e-07
Peak spectrum fit
Power-law model
Time interval is from 42.988 sec. to 43.988 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.63846 ( -0.648451 0.710651 )
Norm@50keV : 2.63177E-03 ( -0.00124611 0.00120098 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.27 using 59 PHA bins.
# Reduced chi-squared = 0.9697 for 57 degrees of freedom
# Null hypothesis probability = 5.401403e-01
Photon flux (15-150 keV) in 1 sec: 0.342329 ( -0.137982 0.138138 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.44934e-08 ( -1.15737e-08 1.26844e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 42.988 sec. to 43.988 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.06351 ( 1.11188 3.2086 )
Epeak [keV] : 40.7553 ( )
Norm@50keV : 0.137791 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.71 using 59 PHA bins.
# Reduced chi-squared = 0.9592 for 56 degrees of freedom
# Null hypothesis probability = 5.619103e-01
Photon flux (15-150 keV) in 1 sec: 0.324249 ( -0.129681 0.134794 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78108e-08 ( -8.67355e-09 1.48803e-08 ) ergs/cm2
Band function
Time interval is from 42.988 sec. to 43.988 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.90015 ( -4.90015 -4.90015 )
beta : -2.65202 ( 2.65202 1.2128 )
Epeak [keV] : 31.3782 ( -31.3782 11.0153 )
Norm@50keV : 88.6035 ( -33.1948 1.67407e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.69 using 59 PHA bins.
# Reduced chi-squared = 0.9579 for 55 degrees of freedom
# Null hypothesis probability = 5.635454e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.1312e-08 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 10.1193 (-3.24757 5.40188)
R^2/D10^2 : 0.171952 (-0.171952 0.529238)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.77 using 59 PHA bins.
# Reduced chi-squared = 0.9432 for 57 degrees of freedom
# Null hypothesis probability = 5.972026e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.600e-09 2.336e-09
25- 50 9.102e-09 5.750e-09
50-150 4.916e-09 4.094e-09
15-150 1.762e-08 1.177e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 99.8407 (-99.8816 -99.8816)
Norm : 1.54101 (-0.663586 1.05738)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.79 using 59 PHA bins.
# Reduced chi-squared = 0.9611 for 57 degrees of freedom
# Null hypothesis probability = 5.586326e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.028e-09 2.557e-09
25- 50 6.962e-09 4.571e-09
50-150 1.127e-08 9.060e-09
15-150 2.226e-08 1.588e-08
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 197.973 (-197.979 -197.979)
R1^2/D10^2 : 2.68190E-05 (-2.68272e-05 0.0205838)
kT2 [keV] : 9.30055 (-9.30054 5.46295)
R2^2/D10^2 : 0.220529 (-0.22057 5.06007)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.71 using 59 PHA bins.
#Fit statistic : Chi-Squared = 53.25 using 59 PHA bins.
# Reduced chi-squared = 0.9765 for 55 degrees of freedom
# Reduced chi-squared = 0.9682 for 55 degrees of freedom
# Null hypothesis probability = 5.240160e-01
# Null hypothesis probability = 5.418054e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.587e-09 2.439e-06
25- 50 8.526e-09 2.299e-05
50-150 5.618e-09 6.085e-04
15-150 1.773e-08 6.330e-04
Plot creation:
Wed Jun 13 19:45:12 EDT 2018