batgrbproduct analysis for trigger=883818
batgrbproduct Analysis for Trigger=883818
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): Tue Jan 15 10:36:46 EST 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger883818/batgroup_hand_proc
======================================================================
Trigger: 00883818 Segment: 000
BAT Trigger Time: 569187094.336 [s; MET]
Trigger Stop: 569187110.72 [s; MET]
UTC: 2019-01-14T19:31:12.086340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 174.882937593776 Dec: 18.8766590141854 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.12
Image Trigger?: NO
Rate S/N Ratio: 9.48683298050514 [ if not an image trigger ]
Image S/N Ratio: 7.12
Flight Position: [ source = BAT ]
RA: 174.882937593776 Dec: 18.8766590141854 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 174.867924180737 Dec: 18.8815145168024 [deg; J2000]
{ 11h 39m 28.3s , +18d 52' 53.5" }
+/- 2.29215061472112 [arcmin] (estimated 90% radius based on SNR)
+/- 1.20730014153505 [arcmin] (formal 1-sigma fit error)
SNR: 9.3000504991092
Angular difference between Flight and Ground position is 0.900758 arcmin
Partial Coding Fraction: 0.6328125 [ including projection effects ]
Duration
T90: 26.4919999837875 +/- 6.69042210499976
Measured from: 0.167999982833862
to: 26.6599999666214 [s; relative to TRIGTIME]
T50: 13.0479999780655 +/- 4.12861484108176
Measured from: 4.44400000572205
to: 17.4919999837875 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 3.62400007247925
to: 4.62400007247925 [s; relative to TRIGTIME]
Total Fluence
Measured from: -1.16399991512299
to: 27.8999999761581 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.309884 0.423022 0.143154 0.045916
0.046547 0.049057 0.044696 0.043927 [error]
Peak 0.028981 0.013750 0.017731 0.025360
0.008819 0.009573 0.008593 0.008429 [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 1.11e-07 1.53e-07 1.56e-07 2.88e-07 5.12e-07 7.08e-07 erg/cm2
Error 2.27e-08 2.33e-08 4.15e-08 1.51e-07 9.59e-08 1.98e-07 erg/cm2
Peak flux Power-law 2.38e-01 1.78e-01 8.88e-02 6.31e-02 5.35e-01 5.68e-01 ph/cm2/s
Error 1.99e-01 8.27e-02 8.35e-02 1.31e-01 2.31e-01 2.55e-01 ph/cm2/s
Fluence Cutoff-PL 1.08e-07 1.66e-07 1.43e-07 7.93e-08 4.67e-07 4.97e-07 erg/cm2
Error 2.45e-08 3.73e-08 6.48e-08 2.19e-07 1.28e-07 2.74e-07 erg/cm2
Peak flux Cutoff-PL 2.54e-01 1.75e-01 7.87e-02 4.94e-02 5.32e-01 5.56e-01 ph/cm2/s
Error 1.99e-01 8.33e-02 -------- -------- 2.31e-01 1.82e-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 1.977 0.283 - - 1.91e-03 3.73e-04 54.720 57
CPL 1.327 1.756 39.2 0.0 4.82e-03 0.00e+00 54.120 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 2.004 1.199 - - 3.56e-03 2.82e-03 60.730 57
CPL 3.248 2.797 353.7 0.0 8.78e-04 0.00e+00 59.830 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 29.064 -1.164 27.900
T90 26.492 0.168 26.660
T50 13.048 4.444 17.492
Peak 1.000 3.624 4.624
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
174.8679 18.8815 0.0207 35.8443 2.3629 0.9408183 9.300 TRIG_00883818
Foreground time interval of the image:
-1.164 27.900 (delta_t = 29.064 [sec])
Background time interval of the image:
-239.336 -1.164 (delta_t = 238.172 [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 -1.164 sec. to 27.900 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.97693 ( -0.272865 0.293731 )
Norm@50keV : 1.91405E-03 ( -0.00037894 0.000367713 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.72 using 59 PHA bins.
# Reduced chi-squared = 0.9599 for 57 degrees of freedom
# Null hypothesis probability = 5.612851e-01
Photon flux (15-150 keV) in 29.06 sec: 0.284104 ( -0.0424034 0.0424035 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.12377e-07 ( -9.41285e-08 9.76788e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.164 sec. to 27.900 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.32666 ( -2.69413 0.817233 )
Epeak [keV] : 39.2459 ( )
Norm@50keV : 4.81791E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.12 using 59 PHA bins.
# Reduced chi-squared = 0.9664 for 56 degrees of freedom
# Null hypothesis probability = 5.464997e-01
Photon flux (15-150 keV) in 29.06 sec: 0.277153 ( -0.046133 0.045091 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.67049e-07 ( -1.24897e-07 1.31188e-07 ) ergs/cm2
Band function
Time interval is from -1.164 sec. to 27.900 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.345434 ( -0.162546 4.82824 )
beta : -2.36941 ( 2.50093 0.630162 )
Epeak [keV] : 32.7138 ( -32.7488 18.5479 )
Norm@50keV : 2.29633E-02 ( -0.0524258 245.875 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.32 using 59 PHA bins.
# Reduced chi-squared = 0.9512 for 55 degrees of freedom
# Null hypothesis probability = 5.778092e-01
Photon flux (15-150 keV) in 29.06 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] : 8.83387 (-1.28067 1.54299)
R^2/D10^2 : 0.216824 (-0.101554 0.183079)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.24 using 59 PHA bins.
# Reduced chi-squared = 1.004 for 57 degrees of freedom
# Null hypothesis probability = 4.660455e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 9.479e-08 2.334e-08
25- 50 1.956e-07 4.575e-08
50-150 7.047e-08 3.201e-08
15-150 3.609e-07 7.717e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 61.7582 (-22.9818 49.8641)
Norm : 1.47487 (-0.335659 0.449011)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.06 using 59 PHA bins.
# Reduced chi-squared = 0.9485 for 57 degrees of freedom
# Null hypothesis probability = 5.859981e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.082e-07 2.161e-08
25- 50 1.661e-07 3.140e-08
50-150 1.936e-07 8.897e-08
15-150 4.679e-07 1.209e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 7.66453 (-1.38522 1.68159)
R1^2/D10^2 : 0.340959 (-0.161694 0.387606)
kT2 [keV] : 55.7694 (-51.7863 -72.5108)
R2^2/D10^2 : 2.27081E-04 (-0.000119553 0.00396642)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.80 using 59 PHA bins.
# Reduced chi-squared = 0.9055 for 55 degrees of freedom
# Null hypothesis probability = 6.729472e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.038e-07 3.997e-08
25- 50 1.803e-07 6.637e-08
50-150 2.431e-07 1.411e-07
15-150 5.272e-07 2.061e-07
Peak spectrum fit
Power-law model
Time interval is from 3.624 sec. to 4.624 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.00433 ( -1.03696 1.3614 )
Norm@50keV : 3.55813E-03 ( -0.00355692 0.00208544 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.73 using 59 PHA bins.
# Reduced chi-squared = 1.065 for 57 degrees of freedom
# Null hypothesis probability = 3.431013e-01
Photon flux (15-150 keV) in 1 sec: 0.534781 ( -0.230992 0.230964 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.28101e-08 ( -1.82067e-08 2.05444e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.624 sec. to 4.624 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.24793 ( -5.21666 0.377941 )
Epeak [keV] : 353.703 ( )
Norm@50keV : 8.77877E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.83 using 59 PHA bins.
# Reduced chi-squared = 1.068 for 56 degrees of freedom
# Null hypothesis probability = 3.386208e-01
Photon flux (15-150 keV) in 1 sec: 0.532139 ( -0.230105 0.231592 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.18824e-08 ( -1.86565e-08 2.24822e-08 ) ergs/cm2
Band function
Time interval is from 3.624 sec. to 4.624 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.53708 ( 1.53878 1.53878 )
beta : -2.00240 ( 2.00403 1.037 )
Epeak [keV] : 12.8104 ( -11.3321 -11.3321 )
Norm@50keV : 1.06606E-02 ( -0.0109914 0.756233 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.73 using 59 PHA bins.
# Reduced chi-squared = 1.104 for 55 degrees of freedom
# Null hypothesis probability = 2.771323e-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] : 5.93491 (-2.24917 4.25007)
R^2/D10^2 : 1.88348 (-1.88348 13.9162)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.44 using 59 PHA bins.
# Reduced chi-squared = 1.095 for 57 degrees of freedom
# Null hypothesis probability = 2.891786e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.676e-09 5.140e-09
25- 50 8.448e-09 6.015e-09
50-150 7.397e-10 7.375e-10
15-150 1.787e-08 1.244e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 72.7090 (-75.8231 -75.8231)
Norm : 2.50652 (-1.29552 11.4664)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.76 using 59 PHA bins.
# Reduced chi-squared = 1.084 for 57 degrees of freedom
# Null hypothesis probability = 3.099257e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.455e-09 4.102e-09
25- 50 1.037e-08 6.665e-09
50-150 1.370e-08 1.316e-08
15-150 3.053e-08 2.133e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.35665 (-2.18124 1.96621)
R1^2/D10^2 : 2.68260 (-2.27494 25.6449)
kT2 [keV] : 84.8824 (-161.63 -183.027)
R2^2/D10^2 : 3.67566E-04 (-8.38342e-05 0.0102177)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.48 using 59 PHA bins.
# Reduced chi-squared = 1.045 for 55 degrees of freedom
# Null hypothesis probability = 3.834173e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.714e-09 5.565e-09
25- 50 8.051e-09 5.115e-09
50-150 2.704e-08 1.581e-08
15-150 4.380e-08 2.373e-08
Plot creation:
Tue Jan 15 10:52:31 EST 2019