batgrbproduct analysis for trigger=894557
batgrbproduct Analysis for Trigger=894557
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): Sun Mar 24 18:44:18 EDT 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger894557/GCN5_download_cron
======================================================================
Trigger: 00894557 Segment: 000
BAT Trigger Time: 575065869.824 [s; MET]
Trigger Stop: 575065869.952 [s; MET]
UTC: 2019-03-23T20:30:47.204380 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 40.1528246982427 Dec: 61.245816597833 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.26
Image Trigger?: NO
Rate S/N Ratio: 11.13552872566 [ if not an image trigger ]
Image S/N Ratio: 7.26
Flight Position: [ source = BAT ]
RA: 40.1528246982427 Dec: 61.245816597833 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 40.1392757265374 Dec: 61.220942845234 [deg; J2000]
{ 02h 40m 33.4s , +61d 13' 15.4" }
+/- 1.77871274244497 [arcmin] (estimated 90% radius based on SNR)
+/- 0.968343020590824 [arcmin] (formal 1-sigma fit error)
SNR: 13.3605506165172
Angular difference between Flight and Ground position is 1.542850 arcmin
Partial Coding Fraction: 0.4375 [ including projection effects ]
Duration
T90: 16.5639998912811 +/- 1.27769318913387
Measured from: 0.128000140190125
to: 16.6920000314713 [s; relative to TRIGTIME]
T50: 9.64800000190735 +/- 3.46114666326306
Measured from: 0.992000102996826
to: 10.6400001049042 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 2.80400002002716
to: 3.80400002002716 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.567999958992004
to: 17.1280000209808 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.574593 0.632683 0.168122 -0.045444
0.053821 0.055342 0.045511 0.038258 [error]
Peak 0.159003 0.187983 0.015759 0.005149
0.015838 0.016699 0.012220 0.009033 [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 2.26e-07 2.43e-07 1.86e-07 2.33e-07 7.43e-07 8.89e-07 erg/cm2
Error 3.01e-08 2.82e-08 3.93e-08 9.06e-08 9.59e-08 1.49e-07 erg/cm2
Peak flux Power-law 2.10e+00 1.13e+00 3.79e-01 1.65e-01 3.70e+00 3.78e+00 ph/cm2/s
Error 3.00e-01 1.44e-01 8.73e-02 6.62e-02 4.39e-01 4.49e-01 ph/cm2/s
Fluence Cutoff-PL 2.02e-07 3.14e-07 1.21e-07 6.32e-09 6.44e-07 6.44e-07 erg/cm2
Error 3.44e-08 4.23e-08 5.23e-08 1.51e-08 8.47e-08 8.55e-08 erg/cm2
Peak flux Cutoff-PL 1.81e+00 1.64e+00 1.45e-01 2.83e-04 3.60e+00 3.60e+00 ph/cm2/s
Error 3.56e-01 2.40e-01 9.08e-02 1.76e-03 4.34e-01 4.34e-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 2.384 0.203 - - 4.32e-03 6.81e-04 60.300 57
CPL -0.241 1.446 30.4 4.9 1.96e-01 1.20e+00 43.730 56
The chi2 of BB fit is 45.75 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 2.576 0.221 - - 1.80e-02 3.24e-03 86.390 57
CPL -2.081 2.286 28.4 2.9 2.22e+01 9.58e+02 64.560 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 17.696 -0.568 17.128
T90 16.564 0.128 16.692
T50 9.648 0.992 10.640
Peak 1.000 2.804 3.804
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
40.1393 +61.2209 0.0144 40.1 -139.8 0.9516 13.4 TRIG_00894557
------------------------------------------
Foreground time interval of the image:
-0.568 8.777 (delta_t = 9.345 [sec])
Background time interval of the image:
-239.824 -117.685 (delta_t = 122.139 [sec])
-116.824 -0.568 (delta_t = 116.256 [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 -0.568 sec. to 17.128 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.38389 ( -0.195306 0.210192 )
Norm@50keV : 4.31972E-03 ( -0.000684057 0.00067793 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.30 using 59 PHA bins.
# Reduced chi-squared = 1.058 for 57 degrees of freedom
# Null hypothesis probability = 3.574881e-01
Photon flux (15-150 keV) in 17.7 sec: 0.791786 ( -0.0857431 0.0857471 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.43103e-07 ( -9.47642e-08 9.70399e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.568 sec. to 17.128 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.240813 ( -1.64994 1.24244 )
Epeak [keV] : 30.4299 ( -5.6185 4.13376 )
Norm@50keV : 0.195972 ( -0.208217 2.18785 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.73 using 59 PHA bins.
# Reduced chi-squared = 0.7810 for 56 degrees of freedom
# Null hypothesis probability = 8.834021e-01
Photon flux (15-150 keV) in 17.7 sec: 0.759386 ( -0.085125 0.08537 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.43579e-07 ( -8.13386e-08 8.80911e-08 ) ergs/cm2
Band function
Time interval is from -0.568 sec. to 17.128 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 0.350944 ( -1.44545 2.22061 )
beta : -9.15965 ( 9.9957 19.9936 )
Epeak [keV] : 30.5744 ( -3.52348 3.99981 )
Norm@50keV : 0.230863 ( -0.230863 11.3821 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.73 using 59 PHA bins.
# Reduced chi-squared = 0.7952 for 55 degrees of freedom
# Null hypothesis probability = 8.627947e-01
Photon flux (15-150 keV) in 17.7 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] : 8.07815 (-0.797142 0.871415)
R^2/D10^2 : 0.886558 (-0.304098 0.467992)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.75 using 59 PHA bins.
# Reduced chi-squared = 0.8027 for 57 degrees of freedom
# Null hypothesis probability = 8.572805e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.865e-07 3.287e-08
25- 50 3.319e-07 4.788e-08
50-150 8.998e-08 2.875e-08
15-150 6.084e-07 8.558e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 35.7727 (-7.33553 9.93279)
Norm : 5.68608 (-1.04253 1.29925)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.48 using 59 PHA bins.
# Reduced chi-squared = 0.8506 for 57 degrees of freedom
# Null hypothesis probability = 7.817125e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.218e-07 3.089e-08
25- 50 2.774e-07 3.744e-08
50-150 1.891e-07 6.315e-08
15-150 6.883e-07 1.003e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.05401 (-5.05401 -5.05401)
R1^2/D10^2 : 2.30291 (-2.30291 -2.30291)
kT2 [keV] : 9.89823 (-9.89823 -9.89823)
R2^2/D10^2 : 0.282167 (-0.282167 0.8114)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.72 using 59 PHA bins.
# Reduced chi-squared = 0.7948 for 55 degrees of freedom
# Null hypothesis probability = 8.632275e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.028e-07 1.107e-07
25- 50 3.127e-07 1.668e-07
50-150 1.263e-07 6.862e-08
15-150 6.417e-07 3.384e-07
Peak spectrum fit
Power-law model
Time interval is from 2.804 sec. to 3.804 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.57583 ( -0.210006 0.231459 )
Norm@50keV : 1.79866E-02 ( -0.00325955 0.00321859 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 86.39 using 59 PHA bins.
# Reduced chi-squared = 1.516 for 57 degrees of freedom
# Null hypothesis probability = 7.236690e-03
Photon flux (15-150 keV) in 1 sec: 3.70415 ( -0.439224 0.439234 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.83782e-07 ( -2.5093e-08 2.5509e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.804 sec. to 3.804 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.08114 ( -2.87961 1.69172 )
Epeak [keV] : 28.4389 ( -3.02422 2.80636 )
Norm@50keV : 22.2047 ( -24.1601 1891.56 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.56 using 59 PHA bins.
# Reduced chi-squared = 1.153 for 56 degrees of freedom
# Null hypothesis probability = 2.024488e-01
Photon flux (15-150 keV) in 1 sec: 3.59666 ( -0.4337 0.43494 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.58688e-07 ( -1.9824e-08 2.0556e-08 ) ergs/cm2
Band function
Time interval is from 2.804 sec. to 3.804 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 2.57985 ( -1.38381 -1.61787 )
beta : -5.51079 ( 4.94426 1.39986 )
Epeak [keV] : 28.6244 ( -3.11199 2.79866 )
Norm@50keV : 48.0911 ( -48.0829 1045.39 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.18 using 59 PHA bins.
# Reduced chi-squared = 1.167 for 55 degrees of freedom
# Null hypothesis probability = 1.858103e-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] : 7.22254 (-0.668871 0.716036)
R^2/D10^2 : 6.82854 (-2.26585 3.43609)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.69 using 59 PHA bins.
# Reduced chi-squared = 1.135 for 57 degrees of freedom
# Null hypothesis probability = 2.261112e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.905e-08 1.100e-08
25- 50 8.585e-08 1.457e-08
50-150 1.591e-08 6.483e-09
15-150 1.608e-07 2.505e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 27.9642 (-5.59915 7.40848)
Norm : 33.0002 (-6.89984 8.85777)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 75.68 using 59 PHA bins.
# Reduced chi-squared = 1.328 for 57 degrees of freedom
# Null hypothesis probability = 4.958023e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.468e-08 8.935e-09
25- 50 7.101e-08 1.107e-08
50-150 3.539e-08 1.398e-08
15-150 1.711e-07 2.460e-08
Double BB
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 200.000 (-200 -200)
R1^2/D10^2 : 1.12114E-04 (-7.21762e-05 0.000272654)
kT2 [keV] : 7.03340 (-0.635944 0.699781)
R2^2/D10^2 : 7.48534 (-2.49417 3.80598)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.69 using 59 PHA bins.
#Fit statistic : Chi-Squared = 58.37 using 59 PHA bins.
# Reduced chi-squared = 1.176 for 55 degrees of freedom
# Reduced chi-squared = 1.061 for 55 degrees of freedom
# Null hypothesis probability = 1.743591e-01
# Null hypothesis probability = 3.525593e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.904e-08 1.247e+00
25- 50 8.586e-08 9.580e+00
50-150 1.592e-08 2.374e+02
15-150 1.608e-07 2.396e+02
Plot creation:
Sun Mar 24 18:48:16 EDT 2019