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: Wed Jan 4 17:30:57 EST 2017
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger727541
======================================================================
Trigger: 00727541 Segment: 000
BAT Trigger Time: 503866136.64 [s; MET]
Trigger Stop: 503866137.152 [s; MET]
UTC: 2016-12-19T18:48:39.308260 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 91.7173166987563 Dec: -26.7900102183723 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.78
Image Trigger?: NO
Rate S/N Ratio: 14.5258390463339 [ if not an image trigger ]
Image S/N Ratio: 7.78
Analysis Position: [ source = BAT ]
RA: 91.7173166987563 Dec: -26.7900102183723 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 91.7159522110343 Dec: -26.8012583033771 [deg; J2000]
{ 06h 06m 51.8s , -26d 48' 04.5" }
+/- 0.877838125941531 [arcmin] (estimated 90% radius based on SNR)
+/- 0.269374713552316 [arcmin] (formal 1-sigma fit error)
SNR: 36.6399519661241
Angular difference between the analysis and refined position is 0.678830 arcmin
Partial Coding Fraction: 0.4921875 [ including projection effects ]
Duration
T90: 6.93199992179871 +/- 0.793180905778267
Measured from: 0.0480000376701355
to: 6.97999995946884 [s; relative to TRIGTIME]
T50: 2.45199990272522 +/- 0.373909090932152
Measured from: 1.42800003290176
to: 3.87999993562698 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.55599999427795
to: 2.55599999427795 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.53600001335144
to: 8.3759999871254 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.777978 1.046229 0.617760 0.131593
0.034686 0.037015 0.031340 0.023604 [error]
Peak 0.160901 0.248936 0.163521 0.046570
0.013290 0.014511 0.012566 0.008831 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 8.912 -0.536 8.376
T90 6.932 0.048 6.980
T50 2.452 1.428 3.880
Peak 1.000 1.556 2.556
====== 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 -1.844 -0.080 0.079 - - - 1.88e-02 -8.79e-04 8.75e-04 53.080 57
CPL -1.294 -0.337 0.367 61.877 -9.264 24.539 3.61e-02 -1.17e-02 1.94e-02 44.960 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: N/A)
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 -1.669 -0.115 0.113 - - - 4.03e-02 -2.89e-03 2.88e-03 91.720 57
CPL -0.852 -0.525 0.604 66.990 -11.792 36.994 1.09e-01 -5.05e-02 1.16e-01 84.240 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 2.96e-07 4.41e-07 4.91e-07 1.03e-06 1.54e-06 2.26e-06 erg/cm2
90%_error_low -2.14e-08 -1.99e-08 -3.06e-08 -1.29e-07 -7.24e-08 -1.57e-07 erg/cm2
90%_error_hi 2.19e-08 1.98e-08 3.05e-08 1.40e-07 7.26e-08 1.65e-07 erg/cm2
Peak flux PL 1.95e+00 1.78e+00 1.12e+00 1.07e+00 5.30e+00 5.92e+00 ph/cm2/s
90%_error_low -2.14e-01 -1.27e-01 -1.00e-01 -1.79e-01 -3.72e-01 -4.05e-01 ph/cm2/s
90%_error_hi 2.20e-01 1.27e-01 9.96e-02 1.98e-01 3.73e-01 4.06e-01 ph/cm2/s
Fluence CPL N/A N/A N/A N/A N/A N/A erg/cm2
90%_error_low -2.14e-08 -1.99e-08 -3.06e-08 -1.29e-07 -7.24e-08 -1.57e-07 erg/cm2
90%_error_hi 2.19e-08 1.98e-08 3.05e-08 1.40e-07 7.26e-08 1.65e-07 erg/cm2
Peak flux CPL 1.89e+00 1.45e+00 7.76e-01 7.04e-01 4.41e+00 4.82e+00 ph/cm2/s
90%_error_low -2.66e-01 -1.59e-01 -1.15e-01 -9.21e-02 -4.42e-01 -3.33e-01 ph/cm2/s
90%_error_hi 2.66e-01 1.63e-01 5.96e-02 7.89e-02 4.74e-01 4.33e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 91.7160 -26.8013 0.0052 39.3860 174.0539 2.6871238 36.640 TRIG_00727541 Foreground time interval of the image: -0.536 8.376 (delta_t = 8.912 [sec]) Background time interval of the image: -239.640 -0.536 (delta_t = 239.104 [sec])
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 -0.536 sec. to 8.376 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.84416 ( -0.0800909 0.0790899 ) Norm@50keV : 1.87926E-02 ( -0.000878568 0.00087453 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 53.08 using 59 PHA bins. # Reduced chi-squared = 0.9312 for 57 degrees of freedom # Null hypothesis probability = 6.230034e-01 Photon flux (15-150 keV) in 8.912 sec: 2.63540 ( -0.12238 0.12267 ) ph/cm2/s Energy fluence (15-150 keV) : 1.54033e-06 ( -7.24028e-08 7.26336e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.536 sec. to 8.376 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.29361 ( -0.337473 0.366627 ) Epeak [keV] : 61.8766 ( -9.26421 24.5389 ) Norm@50keV : 3.61368E-02 ( -0.0117173 0.0194173 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 44.96 using 59 PHA bins. # Reduced chi-squared = 0.8029 for 56 degrees of freedom # Null hypothesis probability = 8.545634e-01 Photon flux (15-150 keV) in 8.912 sec: 2.55482 ( -0.13102 0.13141 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.556 sec. to 2.556 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.6694 ( -0.114646 0.112971 ) Norm@50keV : 4.02942E-02 ( -0.00289238 0.0028778 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 91.72 using 59 PHA bins. # Reduced chi-squared = 1.609 for 57 degrees of freedom # Null hypothesis probability = 2.417836e-03 Photon flux (15-150 keV) in 1 sec: 5.29579 ( -0.37249 0.37294 ) ph/cm2/s Energy fluence (15-150 keV) : 3.74111e-07 ( -2.80999e-08 2.82446e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.556 sec. to 2.556 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.851897 ( -0.525392 0.604212 ) Epeak [keV] : 66.9895 ( -11.7911 36.9951 ) Norm@50keV : 0.108628 ( -0.0505174 0.116262 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 84.24 using 59 PHA bins. # Reduced chi-squared = 1.504 for 56 degrees of freedom # Null hypothesis probability = 8.674589e-03 Photon flux (15-150 keV) in 1 sec: 4.40546 ( -0.44189 0.47416 ) ph/cm2/s Energy fluence (15-150 keV) : 3.54111e-07 ( -3.13434e-08 3.13319e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 6.932 sec. Hardness ratio (energy fluence ratio) = 1.11411506864
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 7.364588e-07 S(50-150 keV) = 8.038739e-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 = -8.165842059037335E-01, IMY = -8.505038678301831E-02
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: -239.640000 -0.536000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.6356 22.0162 0.3 22.3 68.5 9.8289 37.3 0.2 Crab 108.8711 -16.3582 2.2 45.7 147.3 3.6948 5.3 ------ UNKNOWN 82.6723 28.8121 2.6 27.1 56.7 1.3838 4.5 ------ UNKNOWN 41.6312 0.9536 2.3 26.9 -70.4 1.5464 5.1 ------ UNKNOWN 26.0660 25.4912 3.1 45.1 -30.8 1.6815 3.8 ------ UNKNOWN 75.6335 -50.6291 2.8 56.4 -157.5 6.5551 4.1 ------ UNKNOWN 71.4186 -51.7313 4.4 57.2 -154.2 5.0114 2.6 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.536000 8.376000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.6269 22.0372 37.0 22.3 68.4 -0.0168 -0.3 1.4 Crab 78.1352 26.7781 2.2 23.4 50.8 0.2654 5.3 ------ UNKNOWN 91.7161 -26.8004 0.3 39.4 174.1 2.7015 36.8 ------ UNKNOWN 63.2393 -4.9715 2.6 11.5 -126.0 0.1707 4.4 ------ UNKNOWN 23.8612 36.0101 2.4 50.9 -18.7 0.4964 4.8 ------ UNKNOWN 54.4571 -21.9187 2.4 30.5 -126.0 0.2829 4.8 ------ UNKNOWN 72.0510 -49.1232 2.7 54.6 -154.9 0.8275 4.3 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 90.660590 962.455900 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5744 -40.6264 3.4 38.6 -143.1 3.0522 3.4 4.8 Vela X-1 97.0162 13.5643 2.9 40.7 102.4 7.8665 4.0 ------ UNKNOWN 40.4958 -3.3441 3.6 54.2 20.9 12.3530 3.3 ------ UNKNOWN 84.0848 -20.1093 2.8 9.7 46.6 1.9721 4.1 ------ UNKNOWN 26.9853 -20.9249 3.8 58.9 -4.9 12.1937 3.0 ------ UNKNOWN 26.7253 -21.7396 2.5 58.8 -5.9 18.1891 4.6 ------ UNKNOWN 157.6447 -33.7981 3.8 56.4 -151.2 9.6577 3.0 ------ UNKNOWN 124.4898 -62.3410 3.7 41.6 -107.8 8.8334 3.2 ------ UNKNOWN 32.5382 -53.8173 4.0 50.6 -44.6 9.4335 2.9 ------ UNKNOWN