batgrbproduct analysis for trigger=868849
batgrbproduct Analysis for Trigger=868849
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 Oct 27 10:08:11 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger868849/GCN5_download_cron
======================================================================
Trigger: 00868849 Segment: 000
BAT Trigger Time: 562217496 [s; MET]
Trigger Stop: 562217584 [s; MET]
UTC: 2018-10-26T03:31:14.185360 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 244.793202416147 Dec: -16.0004710572437 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 22.15
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 22.15
Flight Position: [ source = BAT ]
RA: 244.793202416147 Dec: -16.0004710572437 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 244.793665050616 Dec: -15.9990347082876 [deg; J2000]
{ 16h 19m 10.5s , -15d 59' 56.5" }
+/- 0.85788146921818 [arcmin] (estimated 90% radius based on SNR)
+/- 0.273503656984285 [arcmin] (formal 1-sigma fit error)
SNR: 37.8636307202119
Angular difference between Flight and Ground position is 0.090217 arcmin
Partial Coding Fraction: 0.5859375 [ including projection effects ]
Duration
T90: 209.799999952316 +/- 54.1532267120429
Measured from: -41.6479998826981
to: 168.152000069618 [s; relative to TRIGTIME]
T50: 101.34399998188 +/- 18.7059055300247
Measured from: -4.5479998588562
to: 96.796000123024 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 47.5920000076294
to: 48.5920000076294 [s; relative to TRIGTIME]
Total Fluence
Measured from: -49.5640000104904
to: 221.539999961853 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 14.385761 0.850834 -0.115922 0.014639
0.179722 0.154828 0.127356 0.107846 [error]
Peak 0.076457 0.013778 0.014796 0.008943
0.011219 0.009370 0.007493 0.006432 [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 5.00e-06 5.34e-07 2.37e-08 1.10e-09 5.55e-06 5.55e-06 erg/cm2
Error 4.32e-07 7.20e-08 8.11e-09 6.41e-10 4.30e-07 4.30e-07 erg/cm2
Peak flux Power-law 8.52e-01 1.58e-01 1.41e-02 1.37e-03 1.02e+00 1.03e+00 ph/cm2/s
Error 2.03e-01 9.17e-02 2.13e-02 4.20e-03 2.57e-01 2.57e-01 ph/cm2/s
Fluence Cutoff-PL 4.88e-06 3.54e-07 9.25e-11 8.17e-19 5.23e-06 5.23e-06 erg/cm2
Error 5.01e-07 8.38e-08 4.83e-10 3.27e-15 5.04e-07 5.04e-07 erg/cm2
Peak flux Cutoff-PL 8.51e-01 1.56e-01 1.38e-02 1.33e-03 1.02e+00 1.02e+00 ph/cm2/s
Error 2.01e-01 -------- 2.13e-02 4.18e-03 2.57e-01 2.57e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band 5.90e-01 4.59e-01 1.15e-01 4.47e-03 1.17e+00 1.17e+00 ph/cm2/s
Error 4.73e-01 2.92e-01 -------- -------- 5.96e-01 -------- ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 6.495 0.310 - - 1.03e-04 2.91e-05 72.440 57
CPL 1.000 0.000 50.0 0.0 1.92e-03 0.00e+00 544.390 56
The chi2 of BB fit is 52.45 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 4.481 1.084 - - 1.08e-03 1.32e-03 53.360 57
CPL 1.000 0.000 50.0 0.0 1.39e-02 0.00e+00 81.900 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 271.104 -49.564 221.540
T90 209.800 -41.648 168.152
T50 101.344 -4.548 96.796
Peak 1.000 47.592 48.592
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
244.7937 -15.9990 0.0051 28.2 -55.6 14.3382 37.9 TRIG_00868849
------------------------------------------
Foreground time interval of the image:
-16.799 45.870 (delta_t = 62.669 [sec])
47.000 221.540 (delta_t = 174.540 [sec])
Background time interval of the image:
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
-49.564000 45.870000
47.000000 221.540000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 6.49459 ( -0.309458 0.311515 )
Norm@50keV : 1.03085E-04 ( -2.57241e-05 3.24197e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.44 using 59 PHA bins.
# Reduced chi-squared = 1.271 for 57 degrees of freedom
# Null hypothesis probability = 8.161100e-02
Photon flux (15-150 keV) in 270 sec: 0.700245 ( -0.0582565 0.0586928 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.55387e-06 ( -4.28433e-07 4.31017e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-49.564000 45.870000
47.000000 221.540000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( )
Epeak [keV] : 50.0000 ( )
Norm@50keV : 1.91735E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 544.39 using 59 PHA bins.
# Reduced chi-squared = 9.7212 for 56 degrees of freedom
# Null hypothesis probability = 3.451815e-81
Photon flux (15-150 keV) in 270 sec: 0.660677 ( -0.070635 0.068624 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.23417e-06 ( -5.11488e-07 4.9734e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-49.564000 45.870000
47.000000 221.540000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.50184 ( -3.20741 3.7064 )
beta : -10.0000 ( 10 10 )
Epeak [keV] : 9.29441 ( -0.877441 2.96074 )
Norm@50keV : 338.458 ( -338.414 121703 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.83 using 59 PHA bins.
# Reduced chi-squared = 0.9605 for 55 degrees of freedom
# Null hypothesis probability = 5.581279e-01
Photon flux (15-150 keV) in 270 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] : 2.50085 (-0.131428 0.144586)
R^2/D10^2 : 329.712 (-125.38 197.933)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.45 using 59 PHA bins.
# Reduced chi-squared = 0.9202 for 57 degrees of freedom
# Null hypothesis probability = 6.461904e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.895e-06 7.330e-07
25- 50 3.604e-07 6.384e-08
50-150 1.142e-10 6.580e-11
15-150 5.256e-06 7.519e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 4.19428 (-0.312503 0.357874)
Norm : 314.176 (-103.826 152.956)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.92 using 59 PHA bins.
# Reduced chi-squared = 0.9634 for 57 degrees of freedom
# Null hypothesis probability = 5.536890e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.999e-06 6.251e-07
25- 50 4.127e-07 7.709e-08
50-150 8.137e-10 4.471e-10
15-150 5.413e-06 6.574e-07
Double BB
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.45 using 59 PHA bins.
#Fit statistic : Chi-Squared = 52.32 using 59 PHA bins.
#Fit statistic : Chi-Squared = 52.29 using 59 PHA bins.
#Fit statistic : Chi-Squared = 52.28 using 59 PHA bins.
# Reduced chi-squared = 0.9537 for 55 degrees of freedom
# Reduced chi-squared = 0.9513 for 55 degrees of freedom
# Reduced chi-squared = 0.9507 for 55 degrees of freedom
# Reduced chi-squared = 0.9505 for 55 degrees of freedom
# Null hypothesis probability = 5.724792e-01
# Null hypothesis probability = 5.775294e-01
# Null hypothesis probability = 5.788406e-01
# Null hypothesis probability = 5.792334e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.895e-06 5.524e+01
25- 50 3.610e-07 4.784e+02
50-150 1.165e-10 9.335e+03
15-150 5.256e-06 1.179e+04
Peak spectrum fit
Power-law model
Time interval is from 47.592 sec. to 48.592 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 4.48078 ( -0.94386 1.22361 )
Norm@50keV : 1.08012E-03 ( -0.00108012 0.00155709 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.36 using 59 PHA bins.
# Reduced chi-squared = 0.9361 for 57 degrees of freedom
# Null hypothesis probability = 6.125943e-01
Photon flux (15-150 keV) in 1 sec: 1.02482 ( -0.25639 0.257585 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.44503e-08 ( -1.00757e-08 1.12947e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 47.592 sec. to 48.592 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( )
Epeak [keV] : 50.0000 ( )
Norm@50keV : 1.38922E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 81.90 using 59 PHA bins.
# Reduced chi-squared = 1.463 for 56 degrees of freedom
# Null hypothesis probability = 1.359880e-02
Photon flux (15-150 keV) in 1 sec: 1.02337 1.01551 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.06554e-15 ( 0 0 ) ergs/cm2
Band function
Time interval is from 47.592 sec. to 48.592 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.75910 ( 1.78083 1.78083 )
beta : -5.94403 ( 5.79078 14.5017 )
Epeak [keV] : 1.78747 ( -1.90943 4.1341 )
Norm@50keV : 0.210105 ( -0.211875 4.27814e+07 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.95 using 59 PHA bins.
# Reduced chi-squared = 0.9627 for 55 degrees of freedom
# Null hypothesis probability = 5.533652e-01
Photon flux (15-150 keV) in 1 sec: 1.16856 ( 5.83144 -0.724514 ) 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] : 3.12123 (-0.671355 0.816323)
R^2/D10^2 : 113.246 (-113.246 424.981)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.96 using 59 PHA bins.
# Reduced chi-squared = 0.9291 for 57 degrees of freedom
# Null hypothesis probability = 6.273682e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.697e-08 1.527e-08
25- 50 4.504e-09 2.937e-09
50-150 9.943e-12 1.151e-11
15-150 3.148e-08 1.857e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 6.57377 (-2.1521 3.60191)
Norm : 97.4950 (-97.495 242.195)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.02 using 59 PHA bins.
# Reduced chi-squared = 0.9301 for 57 degrees of freedom
# Null hypothesis probability = 6.252182e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.614e-08 1.487e-08
25- 50 5.791e-09 3.725e-09
50-150 1.011e-10 1.206e-10
15-150 3.203e-08 1.861e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.02868 (-0.683252 0.80709)
R1^2/D10^2 : 133.115 (-133.128 569.69)
kT2 [keV] : 29.7889 (-29.7525 -29.7525)
R2^2/D10^2 : 2.20061E-03 (-0.00220615 0.154785)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.24 using 59 PHA bins.
# Reduced chi-squared = 0.9317 for 55 degrees of freedom
# Null hypothesis probability = 6.189952e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.670e-08 1.532e-08
25- 50 5.863e-09 3.152e-09
50-150 1.187e-08 8.900e-09
15-150 4.443e-08 2.374e-08
Plot creation:
Sat Oct 27 10:11:57 EDT 2018