batgrbproduct analysis for trigger=921722
batgrbproduct Analysis for Trigger=921722
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): Sat Aug 24 10:20:10 EDT 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger921722/batgroup_hand_proc
======================================================================
Trigger: 00921722 Segment: 000
BAT Trigger Time: 588100227.328 [s; MET]
Trigger Stop: 588100228.736 [s; MET]
UTC: 2019-08-21T17:10:03.878460 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 250.076946712462 Dec: -34.0215900580302 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.8
Image Trigger?: NO
Rate S/N Ratio: 11.2694276695846 [ if not an image trigger ]
Image S/N Ratio: 8.8
Flight Position: [ source = BAT ]
RA: 250.076946712462 Dec: -34.0215900580302 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 250.070237619109 Dec: -34.02651502907 [deg; J2000]
{ 16h 40m 16.9s , -34d 01' 35.5" }
+/- 1.32633082701023 [arcmin] (estimated 90% radius based on SNR)
+/- 0.501644267740459 [arcmin] (formal 1-sigma fit error)
SNR: 20.318957959727
Angular difference between Flight and Ground position is 0.445678 arcmin
Partial Coding Fraction: 0.8359375 [ including projection effects ]
Duration
T90: 57.095999956131 +/- 2.59615098282311
Measured from: -1.07199990749359
to: 56.0240000486374 [s; relative to TRIGTIME]
T50: 32.6839998960495 +/- 2.39003606412485
Measured from: 12.2800000905991
to: 44.9639999866486 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 29.9840000867844
to: 30.9840000867844 [s; relative to TRIGTIME]
Total Fluence
Measured from: -3.30799996852875
to: 59.4920001029968 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.675078 1.744593 0.888540 0.179323
0.075674 0.068286 0.055942 0.045411 [error]
Peak 0.111102 0.146155 0.068012 0.007259
0.011115 0.011109 0.008806 0.006062 [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 5.44e-07 7.26e-07 7.13e-07 1.25e-06 2.39e-06 3.24e-06 erg/cm2
Error 4.35e-08 3.55e-08 5.61e-08 2.06e-07 1.28e-07 2.56e-07 erg/cm2
Peak flux Power-law 1.22e+00 9.47e-01 4.94e-01 3.72e-01 2.83e+00 3.03e+00 ph/cm2/s
Error 1.65e-01 8.94e-02 7.02e-02 9.89e-02 2.69e-01 2.87e-01 ph/cm2/s
Fluence Cutoff-PL 5.13e-07 7.55e-07 7.09e-07 6.47e-07 2.30e-06 2.62e-06 erg/cm2
Error 5.21e-08 4.48e-08 6.01e-08 4.20e-07 1.55e-07 4.54e-07 erg/cm2
Peak flux Cutoff-PL 1.03e+00 1.12e+00 4.93e-01 7.45e-02 2.71e+00 2.72e+00 ph/cm2/s
Error 1.92e-01 1.29e-01 8.95e-02 6.99e-02 2.76e-01 2.83e-01 ph/cm2/s
Fluence Band 4.98e-07 7.63e-07 6.89e-07 9.59e-07 2.30e-06 2.92e-06 erg/cm2
Error 5.56e-08 -------- -------- -------- 1.49e-07 -------- erg/cm2
Peak flux Band 1.02e+00 1.14e+00 4.77e-01 1.33e-01 2.71e+00 2.76e+00 ph/cm2/s
Error 1.98e-01 1.37e-01 9.48e-02 1.39e-01 2.75e-01 3.02e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 2.027 0.097 - - 4.13e-03 2.32e-04 60.350 57
CPL 1.608 0.418 42.1 27.3 6.93e-03 3.79e-03 57.070 56
The chi2 of BB fit is Chi-Squared Chi-Squared 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 1.940 0.160 - - 1.94e-02 2.14e-03 63.380 57
CPL 0.382 0.925 44.3 7.4 1.48e-01 2.88e-01 51.090 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: 49.536000 sec.
T50 in the 50-300 keV band: 33.792000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 62.800 -3.308 59.492
T90 57.096 -1.072 56.024
T50 32.684 12.280 44.964
Peak 1.000 29.984 30.984
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
250.0702 -34.0265 0.0095 22.2724 -122.7599 1.7398844 20.319 TRIG_00921722
Foreground time interval of the image:
-3.308 23.973 (delta_t = 27.281 [sec])
Background time interval of the image:
-239.328 -3.308 (delta_t = 236.020 [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 -3.308 sec. to 59.492 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.02673 ( -0.0962104 0.0980763 )
Norm@50keV : 4.12568E-03 ( -0.000233417 0.000231205 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.35 using 59 PHA bins.
# Reduced chi-squared = 1.059 for 57 degrees of freedom
# Null hypothesis probability = 3.557613e-01
Photon flux (15-150 keV) in 62.8 sec: 0.626583 ( -0.0322153 0.0323162 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.39306e-06 ( -1.27411e-07 1.28184e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.308 sec. to 59.492 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.60842 ( -0.438543 0.39779 )
Epeak [keV] : 42.0943 ( -36.8756 17.6681 )
Norm@50keV : 6.93460E-03 ( -0.00263748 0.004947 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.07 using 59 PHA bins.
# Reduced chi-squared = 1.019 for 56 degrees of freedom
# Null hypothesis probability = 4.349613e-01
Photon flux (15-150 keV) in 62.8 sec: 0.609647 ( -0.035652 0.035789 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.29705e-06 ( -1.54639e-07 1.55826e-07 ) ergs/cm2
Band function
Time interval is from -3.308 sec. to 59.492 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.33027 ( -0.624697 1.80971 )
beta : -2.27449 ( 2.27517 0.246944 )
Epeak [keV] : 38.3572 ( -13.1901 13.7843 )
Norm@50keV : 1.03887E-02 ( -0.00455033 0.260757 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.41 using 59 PHA bins.
# Reduced chi-squared = 1.026 for 55 degrees of freedom
# Null hypothesis probability = 4.221634e-01
Photon flux (15-150 keV) in 62.8 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.30435e-06 ( -2.30391e-06 -1.49992e-07 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 10.7378 ( )
R^2/D10^2 : 0.209768 ( )
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 133.78 using 59 PHA bins.
# Reduced chi-squared = 2.3470 for 57 degrees of freedom
# Null hypothesis probability = 4.088459e-08
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.157e-07 2.989e-08
25- 50 8.651e-07 4.679e-08
50-150 5.529e-07 6.965e-08
15-150 1.734e-06 9.263e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 68.9239 (-10.0418 12.8766)
Norm : 3.02673 (-0.260198 0.290958)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.30 using 59 PHA bins.
# Reduced chi-squared = 1.023 for 57 degrees of freedom
# Null hypothesis probability = 4.273311e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.868e-07 3.595e-08
25- 50 7.713e-07 3.956e-08
50-150 9.793e-07 1.102e-07
15-150 2.238e-06 1.319e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.32648 (-1.22627 1.20974)
R1^2/D10^2 : 1.13785 (-0.503312 1.3424)
kT2 [keV] : 20.3047 (-3.96876 6.7733)
R2^2/D10^2 : 1.24434E-02 (-0.00839222 0.0190325)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.50 using 59 PHA bins.
# Reduced chi-squared = 1.136 for 55 degrees of freedom
# Null hypothesis probability = 2.272110e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.702e-07 8.038e-08
25- 50 7.667e-07 1.368e-07
50-150 1.003e-06 2.985e-07
15-150 2.240e-06 5.426e-07
Peak spectrum fit
Power-law model
Time interval is from 29.984 sec. to 30.984 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.93977 ( -0.156313 0.162955 )
Norm@50keV : 1.93847E-02 ( -0.00215598 0.00212568 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.38 using 59 PHA bins.
# Reduced chi-squared = 1.112 for 57 degrees of freedom
# Null hypothesis probability = 2.615063e-01
Photon flux (15-150 keV) in 1 sec: 2.83008 ( -0.269132 0.269281 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78337e-07 ( -1.91855e-08 1.94181e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 29.984 sec. to 30.984 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.381677 ( -1.02725 0.82367 )
Epeak [keV] : 44.3446 ( -6.13236 8.66744 )
Norm@50keV : 0.148105 ( -0.148107 0.428273 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.09 using 59 PHA bins.
# Reduced chi-squared = 0.9123 for 56 degrees of freedom
# Null hypothesis probability = 6.609753e-01
Photon flux (15-150 keV) in 1 sec: 2.70857 ( -0.27556 0.27598 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.60211e-07 ( -1.9592e-08 2.0734e-08 ) ergs/cm2
Band function
Time interval is from 29.984 sec. to 30.984 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.382526 ( -0.767117 1.0082 )
beta : -10.0000 ( 10 1.77636e-15 )
Epeak [keV] : 44.3400 ( -6.06033 8.64695 )
Norm@50keV : 0.147944 ( -0.147944 0.429172 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.09 using 59 PHA bins.
# Reduced chi-squared = 0.9288 for 55 degrees of freedom
# Null hypothesis probability = 6.249198e-01
Photon flux (15-150 keV) in 1 sec: 2.71294 ( 4.28706 -0.27539 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.62623e-07 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 10.7385 (-0.994475 1.10764)
R^2/D10^2 : 1.06631 (-0.336267 0.480962)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.26 using 59 PHA bins.
# Reduced chi-squared = 1.040 for 57 degrees of freedom
# Null hypothesis probability = 3.930815e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.556e-08 3.815e-09
25- 50 7.004e-08 8.170e-09
50-150 4.477e-08 1.040e-08
15-150 1.404e-07 1.540e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 71.8049 (-16.693 25.4622)
Norm : 14.0346 (-1.90946 2.22471)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.58 using 59 PHA bins.
# Reduced chi-squared = 0.9576 for 57 degrees of freedom
# Null hypothesis probability = 5.663567e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.610e-08 4.515e-09
25- 50 5.783e-08 5.775e-09
50-150 7.568e-08 1.690e-08
15-150 1.696e-07 2.135e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.63077 (-3.78787 3.31047)
R1^2/D10^2 : 3.51109 (-2.2401 76.7026)
kT2 [keV] : 15.8339 (-4.51196 28.1695)
R2^2/D10^2 : 0.159808 (-0.155741 0.644025)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.47 using 59 PHA bins.
# Reduced chi-squared = 0.9357 for 55 degrees of freedom
# Null hypothesis probability = 6.104408e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.166e-08 1.710e-08
25- 50 6.336e-08 3.253e-08
50-150 6.433e-08 3.526e-08
15-150 1.594e-07 8.145e-08
Plot creation:
Sat Aug 24 10:28:37 EDT 2019