batgrbproduct analysis for trigger=821881
batgrbproduct Analysis for Trigger=821881
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 Apr 4 23:21:49 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger821881/GCN5_download_cron
======================================================================
Trigger: 00821881 Segment: 000
BAT Trigger Time: 544495556.416 [s; MET]
Trigger Stop: 544495557.44 [s; MET]
UTC: 2018-04-04T00:45:35.686520 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 83.5636225759874 Dec: -37.1698540029188 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.76
Image Trigger?: NO
Rate S/N Ratio: 13.856406460551 [ if not an image trigger ]
Image S/N Ratio: 8.76
Flight Position: [ source = BAT ]
RA: 83.5636225759874 Dec: -37.1698540029188 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 83.5396414891862 Dec: -37.1681808482558 [deg; J2000]
{ 05h 34m 09.5s , -37d 10' 05.5" }
+/- 1.06439497529973 [arcmin] (estimated 90% radius based on SNR)
+/- 0.414172778282304 [arcmin] (formal 1-sigma fit error)
SNR: 27.8227511788413
Angular difference between Flight and Ground position is 1.150956 arcmin
Partial Coding Fraction: 0.8203125 [ including projection effects ]
Duration
T90: 701.359999895096 +/- 87.9465810827809
Measured from: -12.0559998750687
to: 689.304000020027 [s; relative to TRIGTIME]
T50: 422.899999976158 +/- 94.6472998413403
Measured from: 1.48400008678436
to: 424.384000062943 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.99199998378754
to: 2.99199998378754 [s; relative to TRIGTIME]
Total Fluence
Measured from: -20.7439999580383
to: 742.815999984741 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.806859 0.346702 0.399889 0.113636
0.147255 0.156285 0.138916 0.136138 [error]
Peak 0.046453 0.062457 0.037839 0.012006
0.006739 0.006803 0.005943 0.005112 [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 2.52e-07 2.40e-07 1.59e-07 1.63e-07 7.16e-07 8.14e-07 erg/cm2
Error 8.07e-08 9.55e-08 1.54e-07 2.93e-07 2.98e-07 4.77e-07 erg/cm2
Peak flux Power-law 4.94e-01 4.47e-01 2.79e-01 2.66e-01 1.33e+00 1.49e+00 ph/cm2/s
Error 9.91e-02 5.68e-02 4.95e-02 9.44e-02 1.67e-01 1.87e-01 ph/cm2/s
Fluence Cutoff-PL 2.52e-07 2.39e-07 1.57e-07 1.59e-07 7.14e-07 8.07e-07 erg/cm2
Error 8.01e-08 9.55e-08 8.41e-08 2.91e-07 2.95e-07 3.41e-07 erg/cm2
Peak flux Cutoff-PL 4.94e-01 4.47e-01 2.79e-01 2.64e-01 1.33e+00 1.48e+00 ph/cm2/s
Error 7.66e-02 6.35e-02 5.03e-02 1.84e-01 1.26e-01 2.23e-01 ph/cm2/s
Fluence Band 4.30e-06 6.11e-06 6.24e-06 1.03e-05 2.03e-05 2.71e-05 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 2.592 0.902 - - 9.38e-05 7.47e-05 51.950 57
CPL 1.818 0.000 13.7 0.0 2.25e-04 0.00e+00 53.510 56
=== 1-s peak spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.680 0.224 - - 1.01e-02 1.38e-03 53.860 57
CPL 1.678 0.547 9988.9 -0.0 1.01e-02 0.00e+00 53.860 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: 742.080000 sec.
T50 in the 50-300 keV band: 558.528000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 763.560 -20.744 742.816
T90 701.360 -12.056 689.304
T50 422.900 1.484 424.384
Peak 1.000 1.992 2.992
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
83.5396 -37.1682 0.0069 32.5 -8.8 2.2193 27.8 TRIG_00821881
------------------------------------------
Foreground time interval of the image:
-20.744 17.185 (delta_t = 37.929 [sec])
Background time interval of the image:
-168.915 -20.744 (delta_t = 148.171 [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
-20.744000 636.604000
641.584000 643.114000
646.584000 646.644000
653.584000 653.634000
656.584000 669.904000
670.584000 742.816000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.59153 ( -0.683507 1.12072 )
Norm@50keV : 9.38298E-05 ( -9.36899e-05 5.56582e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.95 using 59 PHA bins.
# Reduced chi-squared = 0.9114 for 57 degrees of freedom
# Null hypothesis probability = 6.645727e-01
Photon flux (15-150 keV) in 744.5 sec: 1.95132E-02 ( -0.0051665 0.00514291 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.16496e-07 ( -2.83075e-07 3.13269e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-20.744000 636.604000
641.584000 643.114000
646.584000 646.644000
653.584000 653.634000
656.584000 669.904000
670.584000 742.816000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.81812 ( )
Epeak [keV] : 13.6680 ( )
Norm@50keV : 2.25199E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.51 using 59 PHA bins.
# Reduced chi-squared = 0.9554 for 56 degrees of freedom
# Null hypothesis probability = 5.698751e-01
Photon flux (15-150 keV) in 744.5 sec: 1.94905E-02 ( -0.0051553 0.005154 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.1361e-07 ( -2.74534e-07 3.16309e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-20.744000 636.604000
641.584000 643.114000
646.584000 646.644000
653.584000 653.634000
656.584000 669.904000
670.584000 742.816000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -5.56476 ( 5.56476 5.56476 )
beta : -2.59373 ( -1.11835 0.684425 )
Epeak [keV] : 3.89574 ( -3.89574 -3.89574 )
Norm@50keV : 1.27327E-02 ( -0.0127315 0.00756704 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.95 using 59 PHA bins.
# Reduced chi-squared = 0.9445 for 55 degrees of freedom
# Null hypothesis probability = 5.919919e-01
Photon flux (15-150 keV) in 744.5 sec: 0.449854 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03014e-05 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 3.49897 (-1.01378 1.94981)
R^2/D10^2 : 0.836644 (-0.836967 5.67042)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.70 using 59 PHA bins.
# Reduced chi-squared = 1.030 for 57 degrees of freedom
# Null hypothesis probability = 4.129437e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.849e-07 1.691e-07
25- 50 6.900e-08 4.303e-08
50-150 3.528e-10 4.035e-10
15-150 3.543e-07 2.032e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 37.9204 (-38.2536 81.9688)
Norm : 0.128579 (-0.0563411 0.553666)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.91 using 59 PHA bins.
# Reduced chi-squared = 0.9633 for 57 degrees of freedom
# Null hypothesis probability = 5.539830e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.157e-07 1.051e-07
25- 50 2.772e-07 1.411e-07
50-150 2.021e-07 1.547e-07
15-150 6.950e-07 3.776e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.76514 (-0.913859 1.16601)
R1^2/D10^2 : 2.74520 (-2.39469 44.3442)
kT2 [keV] : 17.6925 (-6.18755 12.8835)
R2^2/D10^2 : 7.74530E-04 (-0.000665807 0.00288135)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.47 using 59 PHA bins.
# Reduced chi-squared = 0.8448 for 55 degrees of freedom
# Null hypothesis probability = 7.868476e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.625e-07 1.463e-07
25- 50 1.904e-07 1.162e-07
50-150 3.752e-07 2.541e-07
15-150 8.280e-07 4.437e-07
Peak spectrum fit
Power-law model
Time interval is from 1.992 sec. to 2.992 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.67951 ( -0.221772 0.226846 )
Norm@50keV : 1.01005E-02 ( -0.00138981 0.00136433 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.86 using 59 PHA bins.
# Reduced chi-squared = 0.9449 for 57 degrees of freedom
# Null hypothesis probability = 5.936665e-01
Photon flux (15-150 keV) in 1 sec: 1.33199 ( -0.167192 0.167372 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.36779e-08 ( -1.34864e-08 1.37123e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.992 sec. to 2.992 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.67802 ( -0.783977 0.310759 )
Epeak [keV] : 9988.85 ( -9992.38 -9992.39 )
Norm@50keV : 1.01201E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.86 using 59 PHA bins.
# Reduced chi-squared = 0.9618 for 56 degrees of freedom
# Null hypothesis probability = 5.563320e-01
Photon flux (15-150 keV) in 1 sec: 1.33165 ( -0.08515 0.16674 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.36784e-08 ( -1.5448e-08 1.36056e-08 ) ergs/cm2
Band function
Time interval is from 1.992 sec. to 2.992 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.93857 ( -4.93857 -4.93857 )
beta : -1.83343 ( -0.404889 0.271013 )
Epeak [keV] : 24.5365 ( -24.5365 5.75347 )
Norm@50keV : 1309.20 ( -161.336 6.61414e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.66 using 59 PHA bins.
# Reduced chi-squared = 0.9393 for 55 degrees of freedom
# Null hypothesis probability = 6.029329e-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] : 11.2843 (-1.85889 2.35379)
R^2/D10^2 : 0.396856 (-0.198573 0.378934)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.36 using 59 PHA bins.
# Reduced chi-squared = 1.287 for 57 degrees of freedom
# Null hypothesis probability = 7.117895e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.061e-08 2.666e-09
25- 50 3.098e-08 5.065e-09
50-150 2.272e-08 7.440e-09
15-150 6.431e-08 1.195e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 144.062 (-63.6708 -142.237)
Norm : 5.48982 (-0.76783 1.08017)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.51 using 59 PHA bins.
# Reduced chi-squared = 0.9564 for 57 degrees of freedom
# Null hypothesis probability = 5.689546e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.415e-08 7.360e-09
25- 50 2.606e-08 1.023e-08
50-150 5.058e-08 3.042e-08
15-150 9.079e-08 5.225e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.11907 (-1.55743 1.89287)
R1^2/D10^2 : 1.74366 (-0.98566 1.40905)
kT2 [keV] : 35.8250 (-13.9247 74.9468)
R2^2/D10^2 : 5.27724E-03 (-0.00479466 0.0215902)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.28 using 59 PHA bins.
# Reduced chi-squared = 0.9141 for 55 degrees of freedom
# Null hypothesis probability = 6.553904e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.539e-08 6.000e-09
25- 50 2.665e-08 9.908e-09
50-150 5.512e-08 2.967e-08
15-150 9.715e-08 4.063e-08
Plot creation:
Wed Apr 4 23:33:44 EDT 2018