batgrbproduct analysis for trigger=850231
batgrbproduct Analysis for Trigger=850231
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 Jul 28 11:19:02 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger850231/batgroup_hand_proc
======================================================================
Trigger: 00850231 Segment: 000
BAT Trigger Time: 554393750.016 [s; MET]
Trigger Stop: 554393751.04 [s; MET]
UTC: 2018-07-27T14:15:28.684460 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 346.638589844321 Dec: -63.0635521810573 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 18.03
Image Trigger?: NO
Rate S/N Ratio: 49.2138191974571 [ if not an image trigger ]
Image S/N Ratio: 18.03
Flight Position: [ source = BAT ]
RA: 346.638589844321 Dec: -63.0635521810573 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 346.638682341704 Dec: -63.066072614268 [deg; J2000]
{ 23h 06m 33.3s , -63d 03' 57.9" }
+/- 1.11315718085439 [arcmin] (estimated 90% radius based on SNR)
+/- 0.378013336151439 [arcmin] (formal 1-sigma fit error)
SNR: 26.0981128886752
Angular difference between Flight and Ground position is 0.151247 arcmin
Partial Coding Fraction: 0.859375 [ including projection effects ]
Duration
T90: 1.05599999427795 +/- 0.229120086267606
Measured from: 0.0239999294281006
to: 1.07999992370605 [s; relative to TRIGTIME]
T50: 0.452000021934509 +/- 0.0707672428107233
Measured from: 0.25599992275238
to: 0.70799994468689 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0520000457763672
to: 0.947999954223633 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0520000457763672
to: 1.33200001716614 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.148990 0.193082 0.134374 0.018533
0.009851 0.010739 0.009288 0.006924 [error]
Peak 0.129810 0.175371 0.126329 0.017944
0.008712 0.009849 0.008540 0.006074 [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 4.40e-08 7.62e-08 1.01e-07 2.71e-07 2.94e-07 4.91e-07 erg/cm2
Error 4.37e-09 4.87e-09 8.74e-09 4.82e-08 2.11e-08 5.61e-08 erg/cm2
Peak flux Power-law 1.23e+00 1.21e+00 8.29e-01 8.98e-01 3.62e+00 4.16e+00 ph/cm2/s
Error 1.24e-01 7.89e-02 6.78e-02 1.43e-01 2.30e-01 2.67e-01 ph/cm2/s
Fluence Cutoff-PL 3.78e-08 8.48e-08 1.05e-07 7.65e-08 2.74e-07 3.05e-07 erg/cm2
Error 5.25e-09 6.45e-09 1.01e-08 -------- 2.27e-08 4.73e-08 erg/cm2
Peak flux Cutoff-PL 1.02e+00 1.34e+00 9.00e-01 3.21e-01 3.50e+00 3.59e+00 ph/cm2/s
Error 1.49e-01 1.01e-01 8.08e-02 1.40e-01 2.37e-01 2.72e-01 ph/cm2/s
Fluence Band 3.75e-08 8.44e-08 1.05e-07 7.81e-08 2.75e-07 3.06e-07 erg/cm2
Error 4.87e-09 6.20e-09 9.40e-09 -------- 2.21e-08 -------- erg/cm2
Peak flux Band 1.04e+00 1.33e+00 9.00e-01 3.62e-01 3.52e+00 3.64e+00 ph/cm2/s
Error 1.48e-01 1.04e-01 7.90e-02 -------- 2.41e-01 -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.599 0.106 - - 2.27e-02 1.51e-03 57.460 57
CPL 0.588 0.515 67.6 14.8 7.58e-02 5.01e-02 43.230 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 1.540 0.102 - - 2.87e-02 1.88e-03 69.570 57
CPL 0.449 0.511 69.7 14.0 1.05e-01 6.78e-02 52.330 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: 0.832000 sec.
T50 in the 50-300 keV band: 0.384000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 1.384 -0.052 1.332
T90 1.056 0.024 1.080
T50 0.452 0.256 0.708
Peak 1.000 -0.052 0.948
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
346.6387 -63.0661 0.0074 16.9953 53.7999 0.5245691 26.098 TRIG_00850231
Foreground time interval of the image:
-0.052 1.332 (delta_t = 1.384 [sec])
Background time interval of the image:
-239.016 -0.052 (delta_t = 238.964 [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 -0.052 sec. to 1.332 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.59876 ( -0.104776 0.106402 )
Norm@50keV : 2.27103E-02 ( -0.00151234 0.00150414 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.46 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 57 degrees of freedom
# Null hypothesis probability = 4.580432e-01
Photon flux (15-150 keV) in 1.384 sec: 2.91726 ( -0.185247 0.185356 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.93993e-07 ( -2.10039e-08 2.11478e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.052 sec. to 1.332 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.588052 ( -0.545776 0.484203 )
Epeak [keV] : 67.6269 ( -9.58309 20.0558 )
Norm@50keV : 7.57856E-02 ( -0.0326753 0.0674652 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.23 using 59 PHA bins.
# Reduced chi-squared = 0.7720 for 56 degrees of freedom
# Null hypothesis probability = 8.940943e-01
Photon flux (15-150 keV) in 1.384 sec: 2.80694 ( -0.19247 0.1923 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.74473e-07 ( -2.25578e-08 2.2908e-08 ) ergs/cm2
Band function
Time interval is from -0.052 sec. to 1.332 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.587968 ( -0.349313 0.752311 )
beta : -10.0000 ( 10 3.55271e-14 )
Epeak [keV] : 67.6135 ( -9.5802 20.0536 )
Norm@50keV : 7.57941E-02 ( -0.0326806 0.0674967 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.23 using 59 PHA bins.
# Reduced chi-squared = 0.7860 for 55 degrees of freedom
# Null hypothesis probability = 8.747634e-01
Photon flux (15-150 keV) in 1.384 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.74822e-07 ( -2.74813e-07 -2.31003e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.9844 (-0.958851 1.03298)
R^2/D10^2 : 0.432203 (-0.0975403 0.124789)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.16 using 59 PHA bins.
# Reduced chi-squared = 1.248 for 57 degrees of freedom
# Null hypothesis probability = 9.827517e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.471e-08 2.733e-09
25- 50 9.181e-08 7.522e-09
50-150 1.182e-07 1.591e-08
15-150 2.347e-07 1.675e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 158.672 (-39.0815 -158.868)
Norm : 12.1290 (-0.842095 0.899479)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.88 using 59 PHA bins.
# Reduced chi-squared = 0.8576 for 57 degrees of freedom
# Null hypothesis probability = 7.692299e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.290e-08 3.605e-09
25- 50 8.015e-08 1.156e-08
50-150 1.618e-07 6.143e-08
15-150 2.849e-07 7.100e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.82493 (-1.38644 2.4656)
R1^2/D10^2 : 8.51027 (-6.41697 28.9402)
kT2 [keV] : 17.3506 (-1.95278 3.62683)
R2^2/D10^2 : 0.174571 (-0.0984789 0.0876741)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.24 using 59 PHA bins.
# Reduced chi-squared = 0.7861 for 55 degrees of freedom
# Null hypothesis probability = 8.746339e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.951e-08 1.540e-08
25- 50 8.103e-08 1.626e-08
50-150 1.437e-07 2.655e-08
15-150 2.643e-07 4.740e-08
Peak spectrum fit
Power-law model
Time interval is from -0.052 sec. to 0.948 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.54038 ( -0.101711 0.103043 )
Norm@50keV : 2.86945E-02 ( -0.00188634 0.00187848 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.57 using 59 PHA bins.
# Reduced chi-squared = 1.220 for 57 degrees of freedom
# Null hypothesis probability = 1.227152e-01
Photon flux (15-150 keV) in 1 sec: 3.62252 ( -0.230116 0.230241 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.70508e-07 ( -1.92571e-08 1.93715e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.052 sec. to 0.948 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.449360 ( -0.541507 0.479801 )
Epeak [keV] : 69.6771 ( -9.46611 18.4737 )
Norm@50keV : 0.104544 ( -0.0445468 0.0910979 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.33 using 59 PHA bins.
# Reduced chi-squared = 0.9344 for 56 degrees of freedom
# Null hypothesis probability = 6.146787e-01
Photon flux (15-150 keV) in 1 sec: 3.49766 ( -0.23698 0.23669 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.53175e-07 ( -2.0491e-08 2.0748e-08 ) ergs/cm2
Band function
Time interval is from -0.052 sec. to 0.948 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.449252 ( -0.343974 0.72479 )
beta : -10.0000 ( 10 1.77636e-15 )
Epeak [keV] : 69.6633 ( -9.46517 18.4733 )
Norm@50keV : 0.104560 ( -0.0445584 0.091146 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.33 using 59 PHA bins.
# Reduced chi-squared = 0.9514 for 55 degrees of freedom
# Null hypothesis probability = 5.773752e-01
Photon flux (15-150 keV) in 1 sec: 3.52074 ( 3.47926 -0.26659 ) 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] : 14.4569 (-0.973068 1.04748)
R^2/D10^2 : 0.489903 (-0.108146 0.137158)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.49 using 59 PHA bins.
# Reduced chi-squared = 1.359 for 57 degrees of freedom
# Null hypothesis probability = 3.683538e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.155e-08 2.510e-09
25- 50 8.271e-08 6.460e-09
50-150 1.157e-07 1.471e-08
15-150 2.199e-07 1.720e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 188.446 (-51.5239 -190.109)
Norm : 14.9433 (-0.960912 1.01694)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.72 using 59 PHA bins.
# Reduced chi-squared = 1.065 for 57 degrees of freedom
# Null hypothesis probability = 3.432992e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.748e-08 3.200e-09
25- 50 7.161e-08 1.474e-08
50-150 1.541e-07 7.634e-08
15-150 2.632e-07 8.160e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.05757 (-1.53525 3.27708)
R1^2/D10^2 : 8.03717 (-6.30952 28.8357)
kT2 [keV] : 17.7664 (-2.01784 4.86941)
R2^2/D10^2 : 0.206171 (-0.136689 0.105412)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.94 using 59 PHA bins.
# Reduced chi-squared = 0.9625 for 55 degrees of freedom
# Null hypothesis probability = 5.538890e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.354e-08 1.342e-08
25- 50 7.366e-08 1.556e-08
50-150 1.374e-07 2.440e-08
15-150 2.446e-07 4.380e-08
Plot creation:
Sat Jul 28 11:25:05 EDT 2018