batgrbproduct analysis for trigger=975998
batgrbproduct Analysis for Trigger=975998
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 v2.47
Process Start Time (local time): Fri Jun 5 09:14:28 EDT 2020
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger975998/GCN5_download_cron
======================================================================
Trigger: 00975998 Segment: 000
BAT Trigger Time: 612962346.276 [s; MET]
Trigger Stop: 612962346.34 [s; MET]
UTC: 2020-06-04T11:18:41.219420 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 257.19483619524 Dec: -40.127019493857 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 16.03
Image Trigger?: NO
Rate S/N Ratio: 78.2496006379585 [ if not an image trigger ]
Image S/N Ratio: 16.03
Flight Position: [ source = BAT ]
RA: 257.19483619524 Dec: -40.127019493857 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 257.08921095358 Dec: -40.1341335113953 [deg; J2000]
{ 17h 08m 21.4s , -40d 08' 02.9" }
+/- 2.39859394376899 [arcmin] (estimated 90% radius based on SNR)
+/- 1.29736760837517 [arcmin] (formal 1-sigma fit error)
SNR: 8.71611692174575
Angular difference between Flight and Ground position is 4.864285 arcmin
Partial Coding Fraction: 0.890625 [ including projection effects ]
Duration
T90: 52 +/- 15.0332963783729
Measured from: -0.275999903678894
to: 51.7240000963211 [s; relative to TRIGTIME]
T50: 21 +/- 13
Measured from: -0.275999903678894
to: 20.7240000963211 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.276000022888184
to: 0.723999977111816 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.276000022888184
to: 59.7239999771118 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.624746 0.596951 0.059609 0.038299
0.056003 0.053356 0.044848 0.040967 [error]
Peak 0.134089 0.215273 0.060797 -0.002175
0.009450 0.010328 0.007043 0.005499 [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 1.90e-07 1.96e-07 1.43e-07 1.66e-07 5.94e-07 6.95e-07 erg/cm2
Error 2.62e-08 2.50e-08 3.51e-08 7.56e-08 8.37e-08 1.28e-07 erg/cm2
Peak flux Power-law 1.50e+00 1.10e+00 5.39e-01 3.73e-01 3.32e+00 3.52e+00 ph/cm2/s
Error -------- -------- -------- -------- -------- -------- ph/cm2/s
Fluence Cutoff-PL 1.71e-07 2.54e-07 6.17e-08 9.48e-10 4.87e-07 4.87e-07 erg/cm2
Error 3.02e-08 3.62e-08 3.78e-08 4.35e-09 6.53e-08 6.53e-08 erg/cm2
Peak flux Cutoff-PL 1.17e+00 1.60e+00 4.46e-01 1.20e-02 3.23e+00 3.23e+00 ph/cm2/s
Error 1.62e-01 1.29e-01 8.23e-02 -------- 2.30e-01 2.30e-01 ph/cm2/s
Fluence Band 1.63e-07 2.25e-07 7.24e-08 1.45e-08 4.72e-07 4.77e-07 erg/cm2
Error 2.84e-08 -------- -------- -------- 8.37e-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 2.461 0.233 - - 1.00e-03 1.82e-04 57.440 57
CPL -0.866 1.958 28.5 4.0 1.52e-01 3.43e+00 41.220 56
The chi2 of BB fit is 41.28 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 2.034 0.000 - - 2.18e-02 0.00e+00 133.520 57
CPL -1.474 0.921 38.5 2.3 2.79e+00 5.59e+00 54.220 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: 0.320000 sec.
T50 in the 50-300 keV band: 0.192000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 60.000 -0.276 59.724
T90 52.000 -0.276 51.724
T50 21.000 -0.276 20.724
Peak 1.000 -0.276 0.724
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
257.0892 -40.1341 0.0221 14.5 119.0 1.5136 8.7 TRIG_00975998
------------------------------------------
Foreground time interval of the image:
-0.276 59.724 (delta_t = 60.000 [sec])
Background time interval of the image:
-28.975 -0.276 (delta_t = 28.699 [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 -0.276 sec. to 59.724 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.46094 ( -0.224119 0.242878 )
Norm@50keV : 9.99723E-04 ( -0.000181704 0.000182297 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.44 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 57 degrees of freedom
# Null hypothesis probability = 4.588468e-01
Photon flux (15-150 keV) in 60 sec: 0.191786 ( -0.0216434 0.0216456 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.93698e-07 ( -8.20536e-08 8.53548e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.276 sec. to 59.724 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.865644 ( -2.45908 1.45644 )
Epeak [keV] : 28.4660 ( -4.38811 3.59064 )
Norm@50keV : 0.151632 ( -0.185761 6.67968 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.22 using 59 PHA bins.
# Reduced chi-squared = 0.7360 for 56 degrees of freedom
# Null hypothesis probability = 9.303605e-01
Photon flux (15-150 keV) in 60 sec: 0.179686 ( -0.021198 0.021311 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.87135e-07 ( -6.25278e-08 6.80232e-08 ) ergs/cm2
Band function
Time interval is from -0.276 sec. to 59.724 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.10426 ( -1.84277 -0.866056 )
beta : -9.99866 ( 9.99866 0.0013684 )
Epeak [keV] : 28.6635 ( -3.02539 3.34911 )
Norm@50keV : 0.218441 ( -0.023748 6.45711 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.15 using 59 PHA bins.
# Reduced chi-squared = 0.7483 for 55 degrees of freedom
# Null hypothesis probability = 9.170812e-01
Photon flux (15-150 keV) in 60 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 4.72282e-07 ( -4.71862e-07 -7.338e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 7.46775 (-0.731013 0.802545)
R^2/D10^2 : 0.291507 (-0.101309 0.1562)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.28 using 59 PHA bins.
# Reduced chi-squared = 0.7242 for 57 degrees of freedom
# Null hypothesis probability = 9.419122e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.668e-07 3.210e-08
25- 50 2.581e-07 3.939e-08
50-150 5.374e-08 2.069e-08
15-150 4.786e-07 7.368e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 30.7898 (-6.56968 9.1474)
Norm : 1.53141 (-0.312947 0.405961)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.56 using 59 PHA bins.
# Reduced chi-squared = 0.8345 for 57 degrees of freedom
# Null hypothesis probability = 8.090474e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.895e-07 2.766e-08
25- 50 2.196e-07 3.288e-08
50-150 1.244e-07 4.716e-08
15-150 5.335e-07 8.541e-08
Double BB
# Reduced chi-squared = 0.7156 for 55 degrees of freedom
# Reduced chi-squared = 0.7146 for 55 degrees of freedom
# Reduced chi-squared = 0.7140 for 55 degrees of freedom
# Reduced chi-squared = 0.7137 for 55 degrees of freedom
# Reduced chi-squared = 0.7135 for 55 degrees of freedom
# Null hypothesis probability = 9.382481e-01
# Null hypothesis probability = 9.414330e-01
# Null hypothesis probability = 9.435312e-01
# Null hypothesis probability = 9.448590e-01
# Null hypothesis probability = 9.456104e-01
# Null hypothesis probability = 9.460309e-01
# Null hypothesis probability = 9.462544e-01
# Null hypothesis probability = 9.463912e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.660e-07 3.555e-08
25- 50 2.566e-07 4.902e-08
50-150 5.853e-08 2.413e-08
15-150 4.811e-07 8.616e-08
Peak spectrum fit
Power-law model
Time interval is from -0.276 sec. to 0.724 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.03425 ( )
Norm@50keV : 2.17751E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 133.52 using 59 PHA bins.
# Reduced chi-squared = 2.3425 for 57 degrees of freedom
# Null hypothesis probability = 4.419054e-08
Photon flux (15-150 keV) in 1 sec: 3.31875 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.0124e-07 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.276 sec. to 0.724 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.47362 ( -0.991564 0.850221 )
Epeak [keV] : 38.4625 ( -2.15648 2.38841 )
Norm@50keV : 2.78864 ( -2.78929 8.39163 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.22 using 59 PHA bins.
# Reduced chi-squared = 0.9682 for 56 degrees of freedom
# Null hypothesis probability = 5.425751e-01
Photon flux (15-150 keV) in 1 sec: 3.22620 ( -0.22934 0.22982 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.74059e-07 ( -1.3292e-08 1.3756e-08 ) ergs/cm2
Band function
Time interval is from -0.276 sec. to 0.724 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 2.43045 ( -1.19871 2.51407 )
beta : -3.65620 ( 3.84762 0.732211 )
Epeak [keV] : 36.2934 ( -2.73657 3.15632 )
Norm@50keV : 12.4073 ( -11.2527 212.192 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.60 using 59 PHA bins.
# Reduced chi-squared = 0.9564 for 55 degrees of freedom
# Null hypothesis probability = 5.668829e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.83399e-07 ( -1.83392e-07 -1.7812e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 9.88263 (-0.546227 0.578469)
R^2/D10^2 : 1.86273 (-0.380017 0.469661)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.82 using 59 PHA bins.
# Reduced chi-squared = 0.9618 for 57 degrees of freedom
# Null hypothesis probability = 5.571444e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.690e-08 3.990e-09
25- 50 9.021e-08 6.315e-09
50-150 4.550e-08 7.720e-09
15-150 1.726e-07 1.280e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 56.8551 (-8.58813 10.3177)
Norm : 18.7198 (-1.90601 1.98044)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 95.96 using 59 PHA bins.
# Reduced chi-squared = 1.684 for 57 degrees of freedom
# Null hypothesis probability = 9.530390e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.661e-08 4.445e-09
25- 50 6.976e-08 4.810e-09
50-150 7.583e-08 1.271e-08
15-150 1.922e-07 1.515e-08
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.66700 (-9.45268 0.844813)
R1^2/D10^2 : 1.99668 (-0.546539 0.902219)
kT2 [keV] : 193.098 (-190.782 -190.782)
R2^2/D10^2 : 5.52590E-05 (-5.59448e-05 2.33669)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.14 using 59 PHA bins.
#Fit statistic : Chi-Squared = 52.98 using 59 PHA bins.
# Reduced chi-squared = 0.9661 for 55 degrees of freedom
# Reduced chi-squared = 0.9633 for 55 degrees of freedom
# Null hypothesis probability = 5.460859e-01
# Null hypothesis probability = 5.520693e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.807e-08 4.600e-09
25- 50 8.882e-08 1.787e-08
50-150 5.570e-08 2.217e-08
15-150 1.826e-07 4.050e-08
Plot creation:
Fri Jun 5 09:18:37 EDT 2020