Analysis Summary
Notes:
- 1) No attempt has been made to eliminate the non-significant decimal places.
- 2) This batgrbproduct analysis is done using the HEASARC data.
- 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.
======================================================================
BAT GRB EVENT DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.46
Process Start Time: Sun Mar 13 22:07:59 EDT 2016
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger666931
======================================================================
Trigger: 00666931 Segment: 000
BAT Trigger Time: 471409992 [s; MET]
Trigger Stop: 471410072 [s; MET]
UTC: 2015-12-10T03:12:56.468160 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 65.1823076169024 Dec: -71.2304208518608 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.24
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 10.24
Analysis Position: [ source = BAT ]
RA: 65.1823076169024 Dec: -71.2304208518608 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 65.0855808894804 Dec: -71.2265738004778 [deg; J2000]
{ 04h 20m 20.5s , -71d 13' 35.7" }
+/- 1.72137678433548 [arcmin] (estimated 90% radius based on SNR)
+/- 0.710358999811928 [arcmin] (formal 1-sigma fit error)
SNR: 14.0007966958866
Angular difference between the analysis and refined position is 1.881780 arcmin
Partial Coding Fraction: 0.609375 [ including projection effects ]
Duration
T90: 86.9599999785423 +/- 10.6712423189293
Measured from: -38.7200000286102
to: 48.2399999499321 [s; relative to TRIGTIME]
T50: 60.539999961853 +/- 4.92299257607087
Measured from: -21.2960000038147
to: 39.2439999580383 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 38.8199999928474
to: 39.8199999928474 [s; relative to TRIGTIME]
Total Fluence
Measured from: -57.1959999799728
to: 52.8000000119209 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.907443 1.084534 0.555872 0.165159
0.072375 0.075570 0.065892 0.058099 [error]
Peak 0.023274 0.035441 0.035147 0.016641
0.007689 0.008245 0.007455 0.006179 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 109.996 -57.196 52.800
T90 86.960 -38.720 48.240
T50 60.540 -21.296 39.244
Peak 1.000 38.820 39.820
====== Spectral Analysis Summary =====================================
Model : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index : photon index: E^{Ph_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 both the PL model and CPL model
Nomr_90err : 90% error of the normalization
chi2 : Chi-Squared
dof : degree of freedo
=== Time-averaged spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.839 -0.151 0.146 - - - 1.46e-03 -1.43e-04 1.41e-04 58.210 57
CPL -1.052 -0.661 0.799 50.834 -10.019 46.669 4.13e-03 -2.37e-03 7.77e-03 53.970 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: PL)
Model Ph_index Ph_90err_low Ph_90err_hi Epeak Epeak_90err_low Epeak_90err_hi Norm Nomr_90err_low Norm_90err_hi chi2 dof
PL -1.166 -0.375 0.398 - - - 6.90e-03 -1.54e-03 1.54e-03 39.240 57
CPL -0.919 -2.016 1.724 234.083 -234.083 -234.083 9.09e-03 -3.63e-03 4.90e-02 39.140 56
=== 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 PL 2.83e-07 4.23e-07 4.73e-07 1.00e-06 1.48e-06 2.18e-06 erg/cm2
90%_error_low -3.37e-08 -3.46e-08 -6.22e-08 -2.41e-07 -1.44e-07 -3.10e-07 erg/cm2
90%_error_hi 3.44e-08 3.46e-08 6.29e-08 2.88e-07 1.47e-07 3.47e-07 erg/cm2
Peak flux PL 2.06e-01 2.53e-01 2.26e-01 3.48e-01 8.06e-01 1.03e+00 ph/cm2/s
90%_error_low -8.35e-02 -6.92e-02 -5.71e-02 -1.54e-01 -1.86e-01 -2.39e-01 ph/cm2/s
90%_error_hi 9.46e-02 6.69e-02 5.60e-02 2.18e-01 1.87e-01 2.47e-01 ph/cm2/s
Fluence CPL 2.63e-07 4.64e-07 4.58e-07 2.83e-07 1.36e-06 1.47e-06 erg/cm2
90%_error_low -3.84e-08 -4.83e-08 -7.70e-08 -1.78e-07 -1.67e-07 -2.48e-07 erg/cm2
90%_error_hi 3.84e-08 5.02e-08 7.18e-08 5.02e-07 1.75e-07 5.22e-07 erg/cm2
Peak flux CPL 1.96e-01 2.59e-01 2.32e-01 2.63e-01 8.00e-01 9.51e-01 ph/cm2/s
90%_error_low -9.78e-02 -7.31e-02 -6.05e-02 -2.63e-01 -1.89e-01 -2.97e-01 ph/cm2/s
90%_error_hi 9.60e-02 7.91e-02 6.82e-02 1.98e-01 1.90e-01 3.10e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 65.0856 -71.2266 0.0137 24.1221 -87.4798 1.7895174 14.001 TRIG_00666931 Foreground time interval of the image: -10.499 52.800 (delta_t = 63.299 [sec]) Background time interval of the image:
Light Curves
Note: The mask-weighted lightcurves have units of either count/det or counts/sec/det, where a det is 0.4 x 0.4 = 0.16 sq cm.
Full-time range; 1 s binning
Other quick-look light curves:
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
- 64 ms binning (zoomed)
- 16 ms binning (zoomed)
- 8 ms binning (zoomed)
- 2 ms binning (zoomed)
- SN=5 or 10 s binning (full-time range)
- Raw light curve
Spectra
Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using 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.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from -57.196 sec. to 52.800 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.8391 ( -0.151105 0.146357 ) Norm@50keV : 1.46385E-03 ( -0.000142808 0.000140708 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 58.21 using 59 PHA bins. # Reduced chi-squared = 1.021 for 57 degrees of freedom # Null hypothesis probability = 4.306591e-01 Photon flux (15-150 keV) in 110 sec: 0.204866 ( -0.016841 0.016846 ) ph/cm2/s Energy fluence (15-150 keV) : 1.48106e-06 ( -1.4412e-07 1.46556e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -57.196 sec. to 52.800 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.05199 ( -0.660999 0.798868 ) Epeak [keV] : 50.8344 ( -10.0178 46.6702 ) Norm@50keV : 4.12787E-03 ( -0.00236886 0.00776921 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 53.97 using 59 PHA bins. # Reduced chi-squared = 0.9638 for 56 degrees of freedom # Null hypothesis probability = 5.520648e-01 Photon flux (15-150 keV) in 110 sec: 0.198449 ( -0.01765 0.017649 ) ph/cm2/s Energy fluence (15-150 keV) : 1.35989e-06 ( -1.66797e-07 1.75094e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 38.820 sec. to 39.820 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.16568 ( -0.374986 0.397692 ) Norm@50keV : 6.90131E-03 ( -0.0015438 0.00154176 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 39.24 using 59 PHA bins. # Reduced chi-squared = 0.6885 for 57 degrees of freedom # Null hypothesis probability = 9.650001e-01 Photon flux (15-150 keV) in 1 sec: 0.806380 ( -0.186257 0.18707 ) ph/cm2/s Energy fluence (15-150 keV) : 7.07213e-08 ( -1.70478e-08 1.72255e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 38.820 sec. to 39.820 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.919487 ( -2.01579 1.72428 ) Epeak [keV] : 234.083 ( -234.11 -234.11 ) Norm@50keV : 9.08545E-03 ( -0.00363005 0.0489876 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 39.14 using 59 PHA bins. # Reduced chi-squared = 0.6990 for 56 degrees of freedom # Null hypothesis probability = 9.576153e-01 Photon flux (15-150 keV) in 1 sec: 0.800281 ( -0.189388 0.189632 ) ph/cm2/s Energy fluence (15-150 keV) : 6.97028e-08 ( -1.84686e-08 1.76305e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 86.96 sec. Hardness ratio (energy fluence ratio) = 1.11802112891
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 7.059866e-07 S(50-150 keV) = 7.750982e-07
The dash-dotted line and the dashed line traces the fluences calculated from the Band function with Epeak = 15 and 150 keV, respectively. Both lines assume a canonical values of alpha = -1 and beta = -2.5.
Mask shadow pattern
IMX = 1.969010630520137E-02, IMY = 4.473512407426649E-01
Spacecraft aspect plot
Bright source in the pre-burst/pre-slew/post-slew images
Pre-burst image of 15-350 keV band
Time interval of the image:
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -10.499410 52.800000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5104 -40.5548 12.3 46.7 -163.6 0.1815 0.9 0.8 Vela X-1 10.6577 -29.1311 2.7 48.3 -0.7 0.8453 4.2 ------ UNKNOWN 65.0856 -71.2266 0.8 24.1 -87.5 1.7897 14.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 134.500600 963.085500 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.4676 -40.4474 6.8 45.8 166.9 -2.2223 -1.7 7.0 Vela X-1 170.5281 -60.4900 12.0 38.6 -150.0 -0.8794 -1.0 10.1 Cen X-3 186.8396 -62.8769 116.5 40.1 -137.5 0.1055 0.1 8.1 GX 301-2 91.1064 -32.5657 3.0 41.1 113.7 9.4285 3.9 ------ UNKNOWN 145.0184 -42.1137 4.5 47.4 176.8 3.2396 2.6 ------ UNKNOWN 174.1095 -39.3265 4.6 58.7 -159.3 12.1267 2.5 ------ UNKNOWN 317.3837 -47.5726 3.9 50.8 -44.4 8.8640 3.0 ------ UNKNOWN 203.5183 -57.5415 2.7 48.0 -129.1 13.3340 4.3 ------ UNKNOWN