batgrbproduct Analysis for Trigger=668877
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 12:54:56 EST 2015
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger668877/batgroup_hand_proc
======================================================================
Trigger: 00668877 Segment: 000
BAT Trigger Time: 473207176 [s; MET]
Trigger Stop: 473207240 [s; MET]
UTC: 2015-12-30T22:26:00.371600 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 305.94544097376 Dec: 33.8496900052084 [deg; J2000]
Catalogged Source?: YES
Point Source?: YES
GRB Indicated?: NO [ by BAT flight software ]
Image S/N Ratio: 6.06
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 6.06
Flight Position: [ source = BAT ]
RA: 305.94544097376 Dec: 33.8496900052084 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 305.947444489984 Dec: 33.8636997697425 [deg; J2000]
{ 20h 23m 47.4s , +33d 51' 49.3" }
+/- 3.77433238398305 [arcmin] (estimated 90% radius based on SNR)
+/- 1.62299917907958 [arcmin] (formal 1-sigma fit error)
SNR: 4.56101008298395
Angular difference between Flight and Ground position is 0.846493 arcmin
Partial Coding Fraction: 0.8671875 [ including projection effects ]
Duration
T90: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
T50: 64 +/-
Measured from: 0
to: 64 [s; relative to TRIGTIME]
WARNING: battblocks failed. Used TDRSS fore/background intervals
Fluence
Peak Flux (peak 64 second)
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Total Fluence
Measured from: 0
to: 64 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.193806 0.215377 0.013952 0.006963
0.052074 0.051003 0.043186 0.036369 [error]
Peak 0.193806 0.215377 0.013952 0.006963
0.052074 0.051003 0.043186 0.036369 [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 5.33e-08 6.23e-08 5.25e-08 7.49e-08 1.95e-07 2.43e-07 erg/cm2
Error 2.05e-08 2.25e-08 3.31e-08 1.01e-07 8.15e-08 1.40e-07 erg/cm2
Peak flux Power-law 2.73e-02 1.77e-02 7.47e-03 4.30e-03 5.46e-02 5.68e-02 ph/cm2/s
Error 1.07e-02 6.25e-03 4.56e-03 5.43e-03 1.80e-02 1.91e-02 ph/cm2/s
Fluence Cutoff-PL 4.65e-08 9.02e-08 2.73e-08 4.81e-10 1.64e-07 1.65e-07 erg/cm2
Error 3.55e-08 3.50e-08 3.58e-08 1.81e-08 6.14e-08 6.23e-08 erg/cm2
Peak flux Cutoff-PL 2.29e-02 2.56e-02 4.39e-03 4.29e-05 5.30e-02 5.31e-02 ph/cm2/s
Error 1.79e-02 9.71e-03 5.27e-03 1.25e-03 1.73e-02 1.73e-02 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 2.244 0.620 - - 3.22e-04 1.54e-04 67.640 57
CPL -1.330 5.176 32.7 22.1 6.17e-02 6.53e+02 63.950 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 2.244 0.620 - - 3.22e-04 1.54e-04 67.640 57
CPL -1.330 5.176 32.7 22.1 6.17e-02 6.53e+02 63.950 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 64.000 0.000 64.000
T90 64.000 0.000 64.000
T50 64.000 0.000 64.000
Peak 64.000 0.000 64.000
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
305.9474 33.8637 0.0421 14.3744 116.8273 0.4447515 4.561 TRIG_00668877
Foreground time interval of the image:
0.000 64.000 (delta_t = 64.000 [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 0.000 sec. to 64.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.24351 ( -0.554108 0.686415 )
Norm@50keV : 3.22319E-04 ( -0.00015364 0.000154966 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.64 using 59 PHA bins.
# Reduced chi-squared = 1.187 for 57 degrees of freedom
# Null hypothesis probability = 1.581219e-01
Photon flux (15-150 keV) in 64 sec: 5.46002E-02 ( -0.0180108 0.0180805 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.94941e-07 ( -7.71693e-08 8.5744e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.32966 ( -7.12311 3.22941 )
Epeak [keV] : 32.6838 ( -32.7238 11.4392 )
Norm@50keV : 6.16781E-02 ( -0.0738982 1306.06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.95 using 59 PHA bins.
# Reduced chi-squared = 1.142 for 56 degrees of freedom
# Null hypothesis probability = 2.176201e-01
Photon flux (15-150 keV) in 64 sec: 5.29642E-02 ( -0.0171796 0.0173597 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.64419e-07 ( -5.53715e-08 6.7504e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.52392 ( -2.37835 -1.00483 )
beta : -10.0000 ( 9.99375 19.9922 )
Epeak [keV] : 32.8261 ( -10.0623 12.0363 )
Norm@50keV : 8.14393E-02 ( -0.0776271 16.4993 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.93 using 59 PHA bins.
# Reduced chi-squared = 1.162 for 55 degrees of freedom
# Null hypothesis probability = 1.916564e-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] : 8.44883 (-2.12784 2.67588)
R^2/D10^2 : 5.45831E-02 (-0.0545832 0.114538)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.87 using 59 PHA bins.
# Reduced chi-squared = 1.121 for 57 degrees of freedom
# Null hypothesis probability = 2.478298e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.682e-08 2.879e-08
25- 50 8.989e-08 5.533e-08
50-150 2.816e-08 2.251e-08
15-150 1.649e-07 1.005e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 38.9382 (-19.1354 57.0721)
Norm : 0.374067 (-0.162555 0.300477)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.78 using 59 PHA bins.
# Reduced chi-squared = 1.154 for 57 degrees of freedom
# Null hypothesis probability = 1.989518e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.447e-08 3.159e-08
25- 50 7.082e-08 4.380e-08
50-150 5.319e-08 4.550e-08
15-150 1.785e-07 1.121e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.23787 (-3.17073 -3.17073)
R1^2/D10^2 : 0.203152 (-0.23621 -0.23621)
kT2 [keV] : 8.61330 (-8.66956 -8.66956)
R2^2/D10^2 : 4.92047E-02 (-0.0477084 0.120203)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.84 using 59 PHA bins.
# Reduced chi-squared = 1.161 for 55 degrees of freedom
# Null hypothesis probability = 1.936887e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.823e-08 3.354e-08
25- 50 8.868e-08 6.579e-08
50-150 2.929e-08 2.197e-08
15-150 1.662e-07 1.074e-07
Peak spectrum fit
Power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.24351 ( -0.554108 0.686415 )
Norm@50keV : 3.22319E-04 ( -0.00015364 0.000154966 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.64 using 59 PHA bins.
# Reduced chi-squared = 1.187 for 57 degrees of freedom
# Null hypothesis probability = 1.581219e-01
Photon flux (15-150 keV) in 64 sec: 5.46002E-02 ( -0.0180108 0.0180805 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.94941e-07 ( -7.71693e-08 8.5744e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.32966 ( -7.12311 3.22941 )
Epeak [keV] : 32.6838 ( -32.7238 11.439 )
Norm@50keV : 6.16781E-02 ( -0.0738982 1306.06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.95 using 59 PHA bins.
# Reduced chi-squared = 1.142 for 56 degrees of freedom
# Null hypothesis probability = 2.176201e-01
Photon flux (15-150 keV) in 64 sec: 5.29642E-02 ( -0.0171796 0.0173597 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.64419e-07 ( -5.53715e-08 6.7504e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 64.000 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.52392 ( -2.37835 -1.00483 )
beta : -10.0000 ( 9.99375 19.9922 )
Epeak [keV] : 32.8261 ( -10.0623 12.0363 )
Norm@50keV : 8.14393E-02 ( -0.0776272 16.4993 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.93 using 59 PHA bins.
# Reduced chi-squared = 1.162 for 55 degrees of freedom
# Null hypothesis probability = 1.916564e-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] : 8.44883 (-2.12784 2.67588)
R^2/D10^2 : 5.45831E-02 (-0.0545832 0.114538)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.87 using 59 PHA bins.
# Reduced chi-squared = 1.121 for 57 degrees of freedom
# Null hypothesis probability = 2.478298e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.682e-08 2.875e-08
25- 50 8.989e-08 5.466e-08
50-150 2.816e-08 2.310e-08
15-150 1.649e-07 9.898e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 38.9382 (-19.1354 57.0721)
Norm : 0.374067 (-0.162555 0.300477)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.78 using 59 PHA bins.
# Reduced chi-squared = 1.154 for 57 degrees of freedom
# Null hypothesis probability = 1.989518e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.447e-08 3.213e-08
25- 50 7.082e-08 4.278e-08
50-150 5.319e-08 4.531e-08
15-150 1.785e-07 1.136e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.23787 (-3.17073 -3.17073)
R1^2/D10^2 : 0.203152 (-0.23621 -0.23621)
kT2 [keV] : 8.61330 (-8.66956 -8.66956)
R2^2/D10^2 : 4.92047E-02 (-0.0477084 0.120203)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.84 using 59 PHA bins.
# Reduced chi-squared = 1.161 for 55 degrees of freedom
# Null hypothesis probability = 1.936887e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 4.823e-08 3.392e-08
25- 50 8.868e-08 5.843e-08
50-150 2.929e-08 2.133e-08
15-150 1.662e-07 1.074e-07
Plot creation:
Thu Dec 31 13:01:34 EST 2015