batgrbproduct analysis for trigger=831810
batgrbproduct Analysis for Trigger=831810
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): Fri May 11 19:36:35 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger831810/GCN5_download_cron
======================================================================
Trigger: 00831810 Segment: 000
BAT Trigger Time: 547673095.232 [s; MET]
Trigger Stop: 547673096.256 [s; MET]
UTC: 2018-05-10T19:24:34.309920 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 276.318496902141 Dec: -31.9109448076993 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 11.84
Image Trigger?: NO
Rate S/N Ratio: 22.9128784747792 [ if not an image trigger ]
Image S/N Ratio: 11.84
Flight Position: [ source = BAT ]
RA: 276.318496902141 Dec: -31.9109448076993 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 276.335305593463 Dec: -31.9169214987739 [deg; J2000]
{ 18h 25m 20.5s , -31d 55' 00.9" }
+/- 0.787917673267213 [arcmin] (estimated 90% radius based on SNR)
+/- 0.338227895230039 [arcmin] (formal 1-sigma fit error)
SNR: 42.7565732808827
Angular difference between Flight and Ground position is 0.928150 arcmin
Partial Coding Fraction: 0.3789062 [ including projection effects ]
Duration
T90: 40.4319999217987 +/- 10.4113009605627
Measured from: -2.77199983596802
to: 37.6600000858307 [s; relative to TRIGTIME]
T50: 12.7759999036789 +/- 0.856728620326423
Measured from: 5.2480001449585
to: 18.0240000486374 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 5.26400005817413
to: 6.26400005817413 [s; relative to TRIGTIME]
Total Fluence
Measured from: -6.20799994468689
to: 65.7560000419617 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.328876 3.443901 2.965140 0.748155
0.090970 0.091925 0.079237 0.057970 [error]
Peak 0.177400 0.352341 0.436359 0.148642
0.016456 0.019236 0.020018 0.014400 [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 8.30e-07 1.55e-06 2.23e-06 6.79e-06 6.33e-06 1.14e-05 erg/cm2
Error 4.98e-08 5.48e-08 8.03e-08 5.51e-07 2.00e-07 5.94e-07 erg/cm2
Peak flux Power-law 1.97e+00 2.67e+00 2.67e+00 4.81e+00 8.87e+00 1.21e+01 ph/cm2/s
Error 2.15e-01 1.80e-01 1.54e-01 5.85e-01 4.94e-01 7.11e-01 ph/cm2/s
Fluence Cutoff-PL 7.48e-07 1.59e-06 2.32e-06 4.12e-06 6.20e-06 8.78e-06 erg/cm2
Error 6.38e-08 6.00e-08 9.46e-08 1.06e-06 2.14e-07 1.06e-06 erg/cm2
Peak flux Cutoff-PL 1.56e+00 2.75e+00 2.95e+00 2.60e+00 8.64e+00 9.87e+00 ph/cm2/s
Error 2.78e-01 2.00e-01 2.11e-01 7.67e-01 5.08e-01 9.25e-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 1.475 0.055 - - 9.24e-03 2.80e-04 65.540 57
CPL 1.058 0.229 126.7 52.0 1.42e-02 3.34e-03 54.920 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.003 0.090 - - 7.71e-02 4.21e-03 56.740 57
CPL 0.213 0.422 136.8 52.1 1.66e-01 6.84e-02 44.400 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: 50.496000 sec.
T50 in the 50-300 keV band: 10.688000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 71.964 -6.208 65.756
T90 40.432 -2.772 37.660
T50 12.776 5.248 18.024
Peak 1.000 5.264 6.264
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
276.3353 -31.9169 0.0045 34.4 45.1 5.7004 42.8 TRIG_00831810
------------------------------------------
Foreground time interval of the image:
-6.208 8.769 (delta_t = 14.977 [sec])
Background time interval of the image:
-239.232 -6.208 (delta_t = 233.024 [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 -6.208 sec. to 65.756 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.47546 ( -0.0547428 0.0547122 )
Norm@50keV : 9.24071E-03 ( -0.000280078 0.000280075 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.54 using 59 PHA bins.
# Reduced chi-squared = 1.150 for 57 degrees of freedom
# Null hypothesis probability = 2.048402e-01
Photon flux (15-150 keV) in 71.96 sec: 1.14616 ( -0.0385331 0.0386523 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.33429e-06 ( -2.00076e-07 2.00278e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.208 sec. to 65.756 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.05834 ( -0.234538 0.223009 )
Epeak [keV] : 126.746 ( -26.4079 77.5344 )
Norm@50keV : 1.42497E-02 ( -0.00287427 0.00380103 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.92 using 59 PHA bins.
# Reduced chi-squared = 0.9808 for 56 degrees of freedom
# Null hypothesis probability = 5.157003e-01
Photon flux (15-150 keV) in 71.96 sec: 1.11443 ( -0.04156 0.04179 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.20074e-06 ( -2.14599e-07 2.1398e-07 ) ergs/cm2
Band function
Time interval is from -6.208 sec. to 65.756 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.05832 ( -0.18857 0.280679 )
beta : -10.0000 ( 10 1.77636e-15 )
Epeak [keV] : 126.723 ( -20.2178 77.4284 )
Norm@50keV : 1.42487E-02 ( -0.00287367 0.00380305 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.92 using 59 PHA bins.
# Reduced chi-squared = 0.9986 for 55 degrees of freedom
# Null hypothesis probability = 4.775895e-01
Photon flux (15-150 keV) in 71.96 sec: 1.11585 ( ) 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] : 17.5405 ( )
R^2/D10^2 : 7.47484E-02 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 246.17 using 59 PHA bins.
# Reduced chi-squared = 4.3187 for 57 degrees of freedom
# Null hypothesis probability = 2.377152e-25
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.340e-07 2.116e-08
25- 50 1.515e-06 6.440e-08
50-150 3.359e-06 1.709e-07
15-150 5.208e-06 1.835e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-8.7979 -200)
Norm : 4.75193 (-0.144053 0.144053)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.39 using 59 PHA bins.
# Reduced chi-squared = 1.182 for 57 degrees of freedom
# Null hypothesis probability = 1.631868e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.515e-07 2.770e-08
25- 50 1.638e-06 5.505e-08
50-150 3.593e-06 1.115e-07
15-150 6.082e-06 2.083e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.84905 (-0.855815 0.975591)
R1^2/D10^2 : 1.11583 (-0.409673 0.709184)
kT2 [keV] : 25.2785 (-2.02464 2.64333)
R2^2/D10^2 : 1.74842E-02 (-0.00548572 0.00654653)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.22 using 59 PHA bins.
# Reduced chi-squared = 1.022 for 55 degrees of freedom
# Null hypothesis probability = 4.290254e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.301e-07 9.574e-08
25- 50 1.568e-06 1.209e-07
50-150 3.866e-06 2.706e-07
15-150 6.164e-06 3.774e-07
Peak spectrum fit
Power-law model
Time interval is from 5.264 sec. to 6.264 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00266 ( -0.0904473 0.0896834 )
Norm@50keV : 7.70689E-02 ( -0.00421447 0.00420792 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.74 using 59 PHA bins.
# Reduced chi-squared = 0.9954 for 57 degrees of freedom
# Null hypothesis probability = 4.847979e-01
Photon flux (15-150 keV) in 1 sec: 8.87425 ( -0.49357 0.493915 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.32572e-07 ( -4.82779e-08 4.84216e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.264 sec. to 6.264 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.212591 ( -0.443101 0.400654 )
Epeak [keV] : 136.816 ( -28.4014 75.7078 )
Norm@50keV : 0.166444 ( -0.0524773 0.0843861 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.40 using 59 PHA bins.
# Reduced chi-squared = 0.7929 for 56 degrees of freedom
# Null hypothesis probability = 8.681843e-01
Photon flux (15-150 keV) in 1 sec: 8.63609 ( -0.50734 0.50809 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.17901e-07 ( -5.0349e-08 5.0191e-08 ) ergs/cm2
Band function
Time interval is from 5.264 sec. to 6.264 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.212390 ( 0.794742 0.794742 )
beta : -10.0000 ( 10 20 )
Epeak [keV] : 136.782 ( -28.3984 75.709 )
Norm@50keV : 0.166479 ( -0.0524934 0.084443 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.40 using 59 PHA bins.
# Reduced chi-squared = 0.8074 for 55 degrees of freedom
# Null hypothesis probability = 8.458663e-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] : 22.8029 (-1.46316 1.60565)
R^2/D10^2 : 0.295256 (-0.0570055 0.0689001)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.33 using 59 PHA bins.
# Reduced chi-squared = 1.234 for 57 degrees of freedom
# Null hypothesis probability = 1.104787e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.794e-08 3.105e-09
25- 50 1.508e-07 1.195e-08
50-150 5.860e-07 5.020e-08
15-150 7.648e-07 5.330e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.363 ( )
Norm : 36.0241 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 151.95 using 59 PHA bins.
# Reduced chi-squared = 2.6658 for 57 degrees of freedom
# Null hypothesis probability = 1.428037e-10
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.970e-08 5.425e-09
25- 50 1.726e-07 1.380e-08
50-150 3.785e-07 7.945e-08
15-150 6.407e-07 1.138e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.53464 (-1.77226 2.7779)
R1^2/D10^2 : 10.1423 (-7.67644 43.3274)
kT2 [keV] : 26.6055 (-2.52001 3.71804)
R2^2/D10^2 : 0.169413 (-0.0624916 0.0676498)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.74 using 59 PHA bins.
# Reduced chi-squared = 0.7408 for 55 degrees of freedom
# Null hypothesis probability = 9.241366e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.655e-08 2.151e-08
25- 50 1.481e-07 2.325e-08
50-150 6.132e-07 6.550e-08
15-150 8.178e-07 8.725e-08
Plot creation:
Fri May 11 19:43:25 EDT 2018