batgrbproduct Analysis for Trigger=655451
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): Mon Sep 14 09:38:51 EDT 2015
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger655451/GCN5_download_cron
======================================================================
Trigger: 00655451 Segment: 000
BAT Trigger Time: 463837072 [s; MET]
Trigger Stop: 463837136 [s; MET]
UTC: 2015-09-13T11:37:36.871420 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 256.018892334412 Dec: -38.0690195677566 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.79
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 8.79
Flight Position: [ source = BAT ]
RA: 256.018892334412 Dec: -38.0690195677566 [deg; J2000]
Ground Position: [ source = BAT pre-slew burst ]
RA: 255.979563773502 Dec: -38.0789676340444 [deg; J2000]
{ 17h 03m 55.1s , -38d 04' 44.3" }
+/- 4.49484036625321 [arcmin] (estimated 90% radius based on SNR)
+/- 2.59544836047304 [arcmin] (formal 1-sigma fit error)
SNR: 3.55360718566004
Angular difference between Flight and Ground position is 1.951142 arcmin
Partial Coding Fraction: 0.75 [ including projection effects ]
Duration
T90: 278.879999935627 +/- 114.963144253513
Measured from: 67.6560001373291
to: 346.536000072956 [s; relative to TRIGTIME]
T50: 146.811999976635 +/- 199.213848729796
Measured from: 172.528000116348
to: 319.340000092983 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 24.0360000133514
to: 25.0360000133514 [s; relative to TRIGTIME]
Total Fluence
Measured from: -28.4639999866486
to: 352.351999998093 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.885938 1.232973 0.301435 0.098287
0.128229 0.114916 0.093061 0.076009 [error]
Peak 0.024622 0.014409 0.014604 0.002973
0.007643 0.006999 0.005604 0.004677 [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 6.19e-07 5.10e-07 2.85e-07 2.35e-07 1.52e-06 1.65e-06 erg/cm2
Error 7.27e-08 6.02e-08 7.01e-08 1.06e-07 1.75e-07 2.26e-07 erg/cm2
Peak flux Power-law 2.19e-01 1.67e-01 8.54e-02 6.26e-02 5.01e-01 5.35e-01 ph/cm2/s
Error 1.13e-01 5.64e-02 4.74e-02 7.94e-02 1.70e-01 1.81e-01 ph/cm2/s
Fluence Cutoff-PL 5.96e-07 5.73e-07 9.77e-08 1.28e-09 1.27e-06 1.27e-06 erg/cm2
Error 7.91e-08 7.85e-08 9.68e-08 1.65e-08 1.71e-07 1.72e-07 erg/cm2
Peak flux Cutoff-PL 2.23e-01 1.67e-01 8.39e-02 5.92e-02 5.02e-01 5.35e-01 ph/cm2/s
Error 1.15e-01 4.73e-02 5.24e-02 7.89e-02 1.70e-01 1.80e-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 2.840 0.231 - - 4.13e-04 7.52e-05 57.070 57
CPL 0.040 2.437 20.6 0.0 3.67e-02 0.00e+00 49.030 56
The chi2 of BB fit is 50.08 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 1.971 0.711 - - 3.38e-03 1.44e-03 41.170 57
CPL 1.967 1.768 233.8 -0.1 3.41e-03 0.00e+00 41.170 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 380.816 -28.464 352.352
T90 278.880 67.656 346.536
T50 146.812 172.528 319.340
Peak 1.000 24.036 25.036
Image
Pre-slew 15-350 keV image (Event data; bkg subtracted)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
255.9796 -38.0790 0.0542 24.3 150.3 0.5847 3.6 TRIG_00655451
------------------------------------------
Foreground time interval of the image:
-28.464 74.401 (delta_t = 102.865 [sec])
Background time interval of the image:
-239.000 -28.464 (delta_t = 210.536 [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
Multiple GTIs in the spectrum
tstart tstop
-28.464000 187.970000
241.000000 352.352000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.83966 ( -0.221649 0.239612 )
Norm@50keV : 4.13181E-04 ( -7.44515e-05 7.59849e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.07 using 59 PHA bins.
# Reduced chi-squared = 1.001 for 57 degrees of freedom
# Null hypothesis probability = 4.724176e-01
Photon flux (15-150 keV) in 327.8 sec: 0.101383 ( -0.00979601 0.00979724 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.51855e-06 ( -1.72092e-07 1.77296e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-28.464000 187.970000
241.000000 352.352000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 4.00571E-02 ( -3.02129 1.85366 )
Epeak [keV] : 20.6268 ( )
Norm@50keV : 3.66664E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.03 using 59 PHA bins.
# Reduced chi-squared = 0.8756 for 56 degrees of freedom
# Null hypothesis probability = 7.337528e-01
Photon flux (15-150 keV) in 327.8 sec: 9.53844E-02 ( -0.0102356 0.0102236 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.26882e-06 ( -1.57469e-07 1.85125e-07 ) ergs/cm2
Band function
Multiple GTIs in the spectrum
tstart tstop
-28.464000 187.970000
241.000000 352.352000
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 1.79415 ( -1.81317 -0.667605 )
beta : -3.87363 ( 3.84291 0.730295 )
Epeak [keV] : 22.4774 ( -6.95837 3.72066 )
Norm@50keV : 0.874103 ( -0.85419 95.7876 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.09 using 59 PHA bins.
# Reduced chi-squared = 0.8381 for 55 degrees of freedom
# Null hypothesis probability = 7.982752e-01
Photon flux (15-150 keV) in 327.8 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] : 5.96032 (-0.532254 0.587737)
R^2/D10^2 : 0.379543 (-0.132048 0.203941)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.08 using 59 PHA bins.
# Reduced chi-squared = 0.8786 for 57 degrees of freedom
# Null hypothesis probability = 7.300787e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.817e-07 9.588e-08
25- 50 5.717e-07 9.785e-08
50-150 5.095e-08 2.225e-08
15-150 1.204e-06 1.632e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 21.0486 (-3.83279 5.00334)
Norm : 1.15211 (-0.257567 0.34772)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.33 using 59 PHA bins.
# Reduced chi-squared = 0.8830 for 57 degrees of freedom
# Null hypothesis probability = 7.215916e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.109e-07 7.671e-08
25- 50 5.560e-07 7.752e-08
50-150 1.812e-07 7.616e-08
15-150 1.348e-06 1.775e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.55499 (-0.952037 0.748364)
R1^2/D10^2 : 0.492605 (-0.203751 0.460687)
kT2 [keV] : 24.5093 (-15.9197 -24.6216)
R2^2/D10^2 : 2.97133E-04 (-0.000291888 0.0300442)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.53 using 59 PHA bins.
# Reduced chi-squared = 0.8279 for 55 degrees of freedom
# Null hypothesis probability = 8.148439e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.979e-07 1.292e-07
25- 50 5.508e-07 1.468e-07
50-150 2.901e-07 1.908e-07
15-150 1.439e-06 3.329e-07
Peak spectrum fit
Power-law model
Time interval is from 24.036 sec. to 25.036 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.97106 ( -0.651896 0.770061 )
Norm@50keV : 3.38467E-03 ( -0.00151516 0.00137216 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.17 using 59 PHA bins.
# Reduced chi-squared = 0.7224 for 57 degrees of freedom
# Null hypothesis probability = 9.432894e-01
Photon flux (15-150 keV) in 1 sec: 0.501061 ( -0.170356 0.170588 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.11711e-08 ( -1.22305e-08 1.28894e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 24.036 sec. to 25.036 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.96736 ( -2.53884 0.996169 )
Epeak [keV] : 233.801 ( -9962.85 -9963.06 )
Norm@50keV : 3.41208E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.17 using 59 PHA bins.
# Reduced chi-squared = 0.7353 for 56 degrees of freedom
# Null hypothesis probability = 9.310256e-01
Photon flux (15-150 keV) in 1 sec: 0.502000 ( -0.171316 0.16947 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.13659e-08 ( -1.29268e-08 1.24869e-08 ) ergs/cm2
Band function
Time interval is from 24.036 sec. to 25.036 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.73450 ( 1.73937 1.73937 )
beta : -1.95988 ( 1.97584 0.656046 )
Epeak [keV] : 29.4423 ( -26.1714 -26.1714 )
Norm@50keV : 4.99018E-03 ( -0.00267286 0.542948 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.17 using 59 PHA bins.
# Reduced chi-squared = 0.7486 for 55 degrees of freedom
# Null hypothesis probability = 9.167500e-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] : 11.0500 (-5.52807 7.93146)
R^2/D10^2 : 0.151817 (-0.14784 2.06437)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.21 using 59 PHA bins.
# Reduced chi-squared = 0.7931 for 57 degrees of freedom
# Null hypothesis probability = 8.702756e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.877e-09 2.434e-09
25- 50 1.103e-08 6.910e-09
50-150 7.631e-09 5.960e-09
15-150 2.253e-08 1.434e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 77.7467 (-77.7598 -77.7598)
Norm : 2.34073 (-0.997879 2.23491)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.63 using 59 PHA bins.
# Reduced chi-squared = 0.7303 for 57 degrees of freedom
# Null hypothesis probability = 9.370217e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.062e-09 3.829e-09
25- 50 9.910e-09 6.200e-09
50-150 1.372e-08 1.145e-08
15-150 2.969e-08 2.147e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.27439 (-2.36513 4.71178)
R1^2/D10^2 : 5.14325 (-4.88561 15.8114)
kT2 [keV] : 19.6588 (-9.23296 -19.6407)
R2^2/D10^2 : 1.43178E-02 (-0.0141709 0.147516)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.60 using 59 PHA bins.
# Reduced chi-squared = 0.7382 for 55 degrees of freedom
# Null hypothesis probability = 9.265085e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.467e-09 4.444e-09
25- 50 8.066e-09 4.196e-09
50-150 1.516e-08 1.090e-08
15-150 3.069e-08 1.585e-08
Plot creation:
Mon Sep 14 09:43:00 EDT 2015