batgrbproduct analysis for trigger=828953
batgrbproduct Analysis for Trigger=828953
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): Fri Apr 27 11:13:31 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger828953/GCN5_download_cron
======================================================================
Trigger: 00828953 Segment: 000
BAT Trigger Time: 546414968 [s; MET]
Trigger Stop: 546415032 [s; MET]
UTC: 2018-04-26T05:55:47.154240 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 245.196714165135 Dec: -15.5934318368212 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 16.77
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 16.77
Flight Position: [ source = BAT ]
RA: 245.196714165135 Dec: -15.5934318368212 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 245.126422707076 Dec: -15.6167506367183 [deg; J2000]
{ 16h 20m 30.3s , -15d 37' 00.3" }
+/- 1.07006035277647 [arcmin] (estimated 90% radius based on SNR)
+/- 0.331680312873389 [arcmin] (formal 1-sigma fit error)
SNR: 27.6125529198975
Angular difference between Flight and Ground position is 4.296232 arcmin
Partial Coding Fraction: 1 [ including projection effects ]
Duration
T90: 170.139999985695 +/- 27.8999458414072
Measured from: -23.3679999113083
to: 146.772000074387 [s; relative to TRIGTIME]
T50: 103.15600001812 +/- 14.2008185292169
Measured from: 15.7080000638962
to: 118.864000082016 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 124.516000032425
to: 125.516000032425 [s; relative to TRIGTIME]
Total Fluence
Measured from: -48.3480000495911
to: 159.184000015259 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 6.811072 0.537395 -0.128074 0.066913
0.097326 0.089393 0.075046 0.062764 [error]
Peak 0.052524 0.010531 0.009207 0.005607
0.006863 0.006285 0.005143 0.004142 [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 2.18e-06 2.62e-07 1.36e-08 7.38e-10 2.45e-06 2.45e-06 erg/cm2
Error 1.94e-07 3.92e-08 5.10e-09 4.74e-10 1.94e-07 1.94e-07 erg/cm2
Peak flux Power-law 5.09e-01 1.41e-01 2.11e-02 3.58e-03 6.73e-01 6.75e-01 ph/cm2/s
Error 1.21e-01 6.99e-02 2.74e-02 9.13e-03 1.56e-01 1.57e-01 ph/cm2/s
Fluence Cutoff-PL 2.14e-06 1.80e-07 1.20e-10 1.51e-17 2.32e-06 2.32e-06 erg/cm2
Error 2.18e-07 4.86e-08 6.91e-10 7.36e-14 2.21e-07 2.21e-07 erg/cm2
Peak flux Cutoff-PL 5.14e-01 1.31e-01 1.75e-02 2.64e-03 6.66e-01 6.64e-01 ph/cm2/s
Error 1.22e-01 -------- -------- -------- 1.57e-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 6.272 0.335 - - 7.36e-05 2.27e-05 78.700 57
CPL 1.000 0.000 50.0 0.0 1.38e-03 0.00e+00 493.760 56
The chi2 of BB fit is 65.42 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 3.744 1.024 - - 1.36e-03 1.23e-03 59.500 57
CPL 1.862 0.000 1.4 0.0 5.41e-02 0.00e+00 61.090 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: 0.000000 sec.
T50 in the 50-300 keV band: 0.000000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 207.532 -48.348 159.184
T90 170.140 -23.368 146.772
T50 103.156 15.708 118.864
Peak 1.000 124.516 125.516
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
245.1264 -15.6168 0.0070 17.8 -172.0 3.4965 27.6 TRIG_00828953
------------------------------------------
Foreground time interval of the image:
-15.799 71.401 (delta_t = 87.200 [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
Time interval is from -48.348 sec. to 159.184 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 6.27182 ( -0.332552 0.337658 )
Norm@50keV : 7.36063E-05 ( -1.98552e-05 2.54529e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 78.70 using 59 PHA bins.
# Reduced chi-squared = 1.381 for 57 degrees of freedom
# Null hypothesis probability = 3.001480e-02
Photon flux (15-150 keV) in 207.5 sec: 0.398529 ( -0.0339286 0.034174 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.45219e-06 ( -1.93289e-07 1.94299e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -48.348 sec. to 159.184 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.00000 ( )
Epeak [keV] : 50.0000 ( )
Norm@50keV : 1.37679E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 493.76 using 59 PHA bins.
# Reduced chi-squared = 8.8172 for 56 degrees of freedom
# Null hypothesis probability = 2.460857e-71
Photon flux (15-150 keV) in 207.5 sec: 0.379674 ( -0.039817 0.038745 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.32309e-06 ( -2.23644e-07 2.1773e-07 ) ergs/cm2
Band function
Time interval is from -48.348 sec. to 159.184 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -8.68219 ( 5.68971 8.68219 )
beta : -6.30758 ( -0.311656 0.361649 )
Epeak [keV] : 531.892 ( -531.892 -531.892 )
Norm@50keV : 9.67031E-03 ( -0.00251029 0.00366317 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 78.73 using 59 PHA bins.
# Reduced chi-squared = 1.431 for 55 degrees of freedom
# Null hypothesis probability = 1.959345e-02
Photon flux (15-150 keV) in 207.5 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] : 2.56535 (-0.150363 0.166508)
R^2/D10^2 : 155.701 (-62.6963 103.225)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.42 using 59 PHA bins.
# Reduced chi-squared = 1.148 for 57 degrees of freedom
# Null hypothesis probability = 2.076745e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.133e-06 3.201e-07
25- 50 1.739e-07 3.311e-08
50-150 7.051e-11 4.399e-11
15-150 2.307e-06 3.148e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 4.39809 (-0.371457 0.431074)
Norm : 146.404 (-51.102 78.2322)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.30 using 59 PHA bins.
# Reduced chi-squared = 1.163 for 57 degrees of freedom
# Null hypothesis probability = 1.869559e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.172e-06 2.876e-07
25- 50 2.023e-07 4.005e-08
50-150 5.265e-10 3.262e-10
15-150 2.374e-06 3.095e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 2.56814 (-0.179976 0.198119)
R1^2/D10^2 : 154.279 (-62.3173 105.966)
kT2 [keV] : 199.363 (-200 -200)
R2^2/D10^2 : 1.64678E-20 (-2.10447e-06 -2.10447e-06)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.42 using 59 PHA bins.
# Reduced chi-squared = 1.189 for 55 degrees of freedom
# Null hypothesis probability = 1.587528e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.130e-06 3.247e-07
25- 50 1.744e-07 3.296e-08
50-150 7.144e-11 4.215e-11
15-150 2.305e-06 3.170e-07
Peak spectrum fit
Power-law model
Time interval is from 124.516 sec. to 125.516 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.74366 ( -0.865512 1.18284 )
Norm@50keV : 1.36102E-03 ( -0.000953767 0.00150035 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.50 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 57 degrees of freedom
# Null hypothesis probability = 3.848769e-01
Photon flux (15-150 keV) in 1 sec: 0.673461 ( -0.155974 0.156295 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.50458e-08 ( -7.49484e-09 9.00121e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 124.516 sec. to 125.516 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.86231 ( )
Epeak [keV] : 1.44243 ( )
Norm@50keV : 5.41460E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.09 using 59 PHA bins.
# Reduced chi-squared = 1.091 for 56 degrees of freedom
# Null hypothesis probability = 2.981078e-01
Photon flux (15-150 keV) in 1 sec: 0.665929 ( -0.150189 0.164528 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.51864e-08 ( -7.6601e-09 8.8848e-09 ) ergs/cm2
Band function
Time interval is from 124.516 sec. to 125.516 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -9.98066 ( 9.98066 9.98066 )
beta : -3.74453 ( -1.1828 0.866229 )
Epeak [keV] : 2.19893 ( -2.19893 -2.19893 )
Norm@50keV : 0.184835 ( -0.129618 0.203932 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.50 using 59 PHA bins.
# Reduced chi-squared = 1.082 for 55 degrees of freedom
# Null hypothesis probability = 3.153624e-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] : 3.50240 (-0.808737 1.01466)
R^2/D10^2 : 34.6612 (-34.6612 133.425)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.99 using 59 PHA bins.
# Reduced chi-squared = 1.087 for 57 degrees of freedom
# Null hypothesis probability = 3.029132e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.594e-08 8.975e-09
25- 50 3.872e-09 2.437e-09
50-150 1.993e-11 2.241e-11
15-150 1.983e-08 1.121e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 8.38461 (-3.16289 7.15558)
Norm : 32.5432 (-32.5432 82.4384)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.25 using 59 PHA bins.
# Reduced chi-squared = 1.075 for 57 degrees of freedom
# Null hypothesis probability = 3.259988e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.559e-08 8.880e-09
25- 50 5.209e-09 3.313e-09
50-150 2.133e-10 2.357e-10
15-150 2.101e-08 1.238e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.16574 (-0.879179 1.02372)
R1^2/D10^2 : 57.9099 (-45.0699 90.2286)
kT2 [keV] : 21.6069 (-12.1418 -21.59)
R2^2/D10^2 : 7.06800E-03 (-0.00706674 0.0605075)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.76 using 59 PHA bins.
# Reduced chi-squared = 1.032 for 55 degrees of freedom
# Null hypothesis probability = 4.091327e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.562e-08 8.760e-09
25- 50 5.849e-09 3.215e-09
50-150 1.123e-08 8.315e-09
15-150 3.270e-08 1.740e-08
Plot creation:
Fri Apr 27 11:18:47 EDT 2018