batgrbproduct Analysis for Trigger=668879
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 10 downlinks after the trigger.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time (local time): Thu Dec 31 13:02:59 EST 2015
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger668879/batgroup_hand_proc
======================================================================
Trigger: 00668879 Segment: 000
BAT Trigger Time: 473208307.136 [s; MET]
Trigger Stop: 473208315.328 [s; MET]
UTC: 2015-12-30T22:44:51.507520 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 306.015689590842 Dec: 33.8501595497677 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 7.91
Image Trigger?: NO
Rate S/N Ratio: 10.1488915650922 [ if not an image trigger ]
Image S/N Ratio: 7.91
Flight Position: [ source = BAT ]
RA: 306.015689590842 Dec: 33.8501595497677 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 305.988635553082 Dec: 33.8524042654816 [deg; J2000]
{ 20h 23m 57.3s , +33d 51' 08.7" }
+/- 1.63467657021393 [arcmin] (estimated 90% radius based on SNR)
+/- 0.577473419716386 [arcmin] (formal 1-sigma fit error)
SNR: 15.0735572365866
Angular difference between Flight and Ground position is 1.354792 arcmin
Partial Coding Fraction: 1 [ including projection effects ]
Duration
T90: 64 +/- 22.6274169979695
Measured from: -15.1359999775887
to: 48.8640000224113 [s; relative to TRIGTIME]
T50: 16 +/- 16
Measured from: 0.864000022411346
to: 16.8640000224113 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 8.36400002241135
to: 9.36400002241135 [s; relative to TRIGTIME]
Total Fluence
Measured from: -15.1359999775887
to: 48.8640000224113 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.487726 0.505166 0.439835 0.093683
0.052146 0.051250 0.044527 0.039591 [error]
Peak 0.007931 0.014022 0.011441 -0.000785
0.006541 0.006432 0.005675 0.005002 [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 1.13e-07 2.16e-07 3.19e-07 1.01e-06 9.01e-07 1.66e-06 erg/cm2
Error 2.04e-08 2.31e-08 4.32e-08 3.02e-07 1.04e-07 3.33e-07 erg/cm2
Peak flux Power-law 7.45e-02 7.97e-02 6.06e-02 7.50e-02 2.43e-01 2.90e-01 ph/cm2/s
Error 7.61e-02 6.45e-02 4.28e-02 1.24e-01 1.44e-01 1.77e-01 ph/cm2/s
Fluence Cutoff-PL 1.13e-07 2.17e-07 3.17e-07 9.95e-07 8.96e-07 1.57e-06 erg/cm2
Error 1.56e-08 2.30e-08 4.26e-08 4.19e-07 1.03e-07 4.46e-07 erg/cm2
Peak flux Cutoff-PL 6.44e-02 8.88e-02 6.46e-02 2.72e-02 2.36e-01 2.46e-01 ph/cm2/s
Error 7.39e-02 4.94e-02 5.88e-02 6.87e-02 1.43e-01 1.79e-01 ph/cm2/s
Fluence Band -------- -------- -------- -------- -------- -------- erg/cm2
Error -------- -------- -------- -------- -------- -------- erg/cm2
Peak flux Band 6.57e-02 8.70e-02 6.48e-02 3.29e-02 2.38e-01 2.50e-01 ph/cm2/s
Error 7.40e-02 -------- -------- -------- 1.43e-01 1.82e-01 ph/cm2/s
=== Time-averaged spectral analysis ===
Model Ph_index Ph_90err Epeak Epeak_90err Norm Nomr_90err chi2 dof
PL 1.440 0.185 - - 1.47e-03 1.51e-04 55.390 57
CPL 1.432 0.186 9999.3 0.0 1.47e-03 1.20e-03 55.410 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 1.397 1.085 - - 2.00e-03 1.59e-03 59.220 57
CPL 0.439 6.814 78.2 0.0 6.37e-03 0.00e+00 58.930 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: 36.928000 sec.
T50 in the 50-300 keV band: 19.008000 sec.
=== Table of the duration information ==
Value tstart tstop
T100 64.000 -15.136 48.864
T90 64.000 -15.136 48.864
T50 16.000 0.864 16.864
Peak 1.000 8.364 9.364
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
305.9886 33.8524 0.0128 0.0452 143.4648 1.5512219 15.074 TRIG_00668879
Foreground time interval of the image:
-15.136 48.864 (delta_t = 64.000 [sec])
Background time interval of the image:
-239.136 -15.136 (delta_t = 224.000 [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 -15.136 sec. to 48.864 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.44034 ( -0.185362 0.185315 )
Norm@50keV : 1.46824E-03 ( -0.000151789 0.000150906 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.39 using 59 PHA bins.
# Reduced chi-squared = 0.9718 for 57 degrees of freedom
# Null hypothesis probability = 5.355693e-01
Photon flux (15-150 keV) in 64 sec: 0.180511 ( -0.0185054 0.0185506 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.00819e-07 ( -1.03761e-07 1.04954e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.136 sec. to 48.864 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.43229 ( -0.184848 0.188088 )
Epeak [keV] : 9999.30 ( -9999.36 -9999.36 )
Norm@50keV : 1.47291E-03 ( -0.00147334 0.00092458 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.41 using 59 PHA bins.
# Reduced chi-squared = 0.9894 for 56 degrees of freedom
# Null hypothesis probability = 4.972466e-01
Photon flux (15-150 keV) in 64 sec: 0.180717 ( -0.018713 0.0183 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.96224e-07 ( -9.94176e-08 1.07354e-07 ) ergs/cm2
Band function
Time interval is from -15.136 sec. to 48.864 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.96467 ( -4.96467 -4.96467 )
beta : -1.49450 ( -0.23641 0.201935 )
Epeak [keV] : 22.5139 ( -22.5139 6.25179 )
Norm@50keV : 266.127 ( -26.6642 666471 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.55 using 59 PHA bins.
# Reduced chi-squared = 0.9918 for 55 degrees of freedom
# Null hypothesis probability = 4.917759e-01
Photon flux (15-150 keV) in 64 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] : 15.3019 (-2.30734 2.83047)
R^2/D10^2 : 1.84788E-02 (-0.00813213 0.0142171)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 91.75 using 59 PHA bins.
# Reduced chi-squared = 1.610 for 57 degrees of freedom
# Null hypothesis probability = 2.405578e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.778e-08 1.161e-08
25- 50 2.338e-07 4.032e-08
50-150 3.758e-07 8.512e-08
15-150 6.673e-07 9.939e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 (-53.1245 -200)
Norm : 0.738896 (-0.0745087 0.0745087)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.91 using 59 PHA bins.
# Reduced chi-squared = 1.016 for 57 degrees of freedom
# Null hypothesis probability = 4.413838e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.178e-07 2.534e-08
25- 50 2.265e-07 1.221e-07
50-150 4.968e-07 2.697e-07
15-150 8.412e-07 4.246e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.85561 (-1.52511 1.91364)
R1^2/D10^2 : 0.226954 (-0.130417 0.346808)
kT2 [keV] : 34.8006 (-10.0796 28.1341)
R2^2/D10^2 : 1.02020E-03 (-0.00080333 0.00200736)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.96 using 59 PHA bins.
# Reduced chi-squared = 0.9629 for 55 degrees of freedom
# Null hypothesis probability = 5.529593e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.185e-07 4.853e-08
25- 50 2.144e-07 7.482e-08
50-150 6.050e-07 3.174e-07
15-150 9.379e-07 3.606e-07
Peak spectrum fit
Power-law model
Time interval is from 8.364 sec. to 9.364 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.39705 ( -1.09191 1.07784 )
Norm@50keV : 1.99890E-03 ( -0.00199905 0.00118851 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.22 using 59 PHA bins.
# Reduced chi-squared = 1.039 for 57 degrees of freedom
# Null hypothesis probability = 3.943890e-01
Photon flux (15-150 keV) in 1 sec: 0.243249 ( -0.14307 0.144375 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.93299e-08 ( -1.21408e-08 1.30862e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.364 sec. to 9.364 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.439216 ( -6.39255 7.23571 )
Epeak [keV] : 78.2138 ( -78.0902 -78.0902 )
Norm@50keV : 6.37159E-03 ( -0.00645095 -0.00645095 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.93 using 59 PHA bins.
# Reduced chi-squared = 1.052 for 56 degrees of freedom
# Null hypothesis probability = 3.689409e-01
Photon flux (15-150 keV) in 1 sec: 0.236133 ( -0.14051 0.145064 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.79201e-08 ( -1.31816e-08 1.37811e-08 ) ergs/cm2
Band function
Time interval is from 8.364 sec. to 9.364 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.435625 ( -5.17427 0.805793 )
beta : -10.0000 ( 10 10 )
Epeak [keV] : 76.4162 ( -56.8817 -76.5507 )
Norm@50keV : 6.55270E-03 ( -0.0065316 22.6972 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.93 using 59 PHA bins.
# Reduced chi-squared = 1.071 for 55 degrees of freedom
# Null hypothesis probability = 3.338964e-01
Photon flux (15-150 keV) in 1 sec: 0.238376 ( 6.76162 -0.142572 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.86653e-08 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 15.3794 (-15.4256 26.1613)
R^2/D10^2 : 2.63011E-02 (-0.025897 0.701866)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.51 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 57 degrees of freedom
# Null hypothesis probability = 3.843191e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.297e-09 9.170e-10
25- 50 5.271e-09 3.557e-09
50-150 8.577e-09 6.425e-09
15-150 1.514e-08 1.159e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 199.360 (-199.362 -199.362)
Norm : 1.00896 (-0.587244 0.917423)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.13 using 59 PHA bins.
# Reduced chi-squared = 1.037 for 57 degrees of freedom
# Null hypothesis probability = 3.976468e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.512e-09 1.806e-09
25- 50 4.833e-09 3.500e-09
50-150 1.060e-08 7.265e-09
15-150 1.794e-08 1.247e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.91648 (-7.14814 87.0057)
R1^2/D10^2 : 0.263371 (-0.258499 -0.258499)
kT2 [keV] : 25.8930 (-26.2518 -26.2518)
R2^2/D10^2 : 3.42295E-03 (-0.00329479 0.374776)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.53 using 59 PHA bins.
# Reduced chi-squared = 1.064 for 55 degrees of freedom
# Null hypothesis probability = 3.473030e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.390e-09 1.819e-09
25- 50 4.932e-09 3.340e-09
50-150 1.159e-08 9.040e-09
15-150 1.891e-08 1.029e-08
Plot creation:
Thu Dec 31 13:10:32 EST 2015