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 v2.48
Process Start Time: Wed Jun 14 12:15:58 EDT 2023
Host Name: batproc1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1131397
======================================================================
Trigger: 01131397 Segment: 000
BAT Trigger Time: 688590848.896 [s; MET]
Trigger Stop: 688590849.92 [s; MET]
UTC: 2022-10-27T19:13:38.784400 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 225.602970286955 Dec: 47.4481624691975 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 14.69
Image Trigger?: NO
Rate S/N Ratio: 22.2710574513201 [ if not an image trigger ]
Image S/N Ratio: 14.69
Analysis Position: [ source = BAT ]
RA: 225.602970286955 Dec: 47.4481624691975 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 225.600737176053 Dec: 47.4525858854227 [deg; J2000]
{ 15h 02m 24.2s , +47d 27' 09.3" }
+/- 1.6146741935712 [arcmin] (estimated 90% radius based on SNR)
+/- 0.602663596532404 [arcmin] (formal 1-sigma fit error)
SNR: 15.3410198212875
Angular difference between the analysis and refined position is 0.280445 arcmin
Partial Coding Fraction: 0.4570312 [ including projection effects ]
Duration
T90: 8.84800004959106 +/- 1.53633333421838
Measured from: -5.31200003623962
to: 3.53600001335144 [s; relative to TRIGTIME]
T50: 1.7279999256134 +/- 2.51031801570599
Measured from: -0.575999975204468
to: 1.15199995040894 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.108000040054321
to: 0.891999959945679 [s; relative to TRIGTIME]
Total Fluence
Measured from: -6.5440000295639
to: 4.19200003147125 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.422160 0.477524 0.148096 0.021677
0.037005 0.037516 0.031298 0.026756 [error]
Peak 0.131527 0.170281 0.055992 0.009433
0.013351 0.014454 0.011422 0.008143 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 10.736 -6.544 4.192
T90 8.848 -5.312 3.536
T50 1.728 -0.576 1.152
Peak 1.000 -0.108 0.892
====== 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 -2.365 -0.204 0.191 - - - 5.52e-03 -7.92e-04 7.78e-04 67.350 57
CPL -1.137 -0.860 1.890 25.125 -24.113 7.513 3.29e-02 -3.29e-02 5.65e-01 63.820 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 -2.173 -0.186 0.175 - - - 2.11e-02 -2.90e-03 2.85e-03 69.450 57
CPL -0.071 -1.084 1.462 34.667 -5.515 5.288 4.13e-01 -4.13e-01 3.22e+00 55.950 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 1.72e-07 1.87e-07 1.45e-07 1.86e-07 5.74e-07 6.90e-07 erg/cm2
90%_error_low -2.20e-08 -1.94e-08 -2.77e-08 -6.00e-08 -6.56e-08 -1.00e-07 erg/cm2
90%_error_hi 2.24e-08 1.92e-08 2.88e-08 7.67e-08 6.69e-08 1.12e-07 erg/cm2
Peak flux PL 1.66e+00 1.13e+00 4.99e-01 3.06e-01 3.44e+00 3.59e+00 ph/cm2/s
90%_error_low -2.31e-01 -1.22e-01 -8.65e-02 -8.74e-02 -3.70e-01 -3.86e-01 ph/cm2/s
90%_error_hi 2.36e-01 1.22e-01 8.80e-02 1.05e-01 3.70e-01 3.87e-01 ph/cm2/s
Fluence CPL N/A N/A N/A N/A N/A N/A erg/cm2
90%_error_low -2.20e-08 -1.94e-08 -2.77e-08 -6.00e-08 -6.56e-08 -1.00e-07 erg/cm2
90%_error_hi 2.24e-08 1.92e-08 2.88e-08 7.67e-08 6.69e-08 1.12e-07 erg/cm2
Peak flux CPL 1.47e+00 1.43e+00 4.23e-01 2.64e-02 3.35e+00 3.35e+00 ph/cm2/s
90%_error_low -2.59e-01 -1.90e-01 -1.41e-01 -2.64e-02 -3.69e-01 -3.70e-01 ph/cm2/s
90%_error_hi 2.61e-01 1.96e-01 1.28e-01 6.55e-02 3.71e-01 3.72e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 225.6007 47.4526 0.0125 42.6614 177.4083 1.0924919 15.341 TRIG_01131397 Foreground time interval of the image: -6.544 4.192 (delta_t = 10.736 [sec]) Background time interval of the image: -239.896 -6.544 (delta_t = 233.352 [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 -6.544 sec. to 4.192 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.36473 ( -0.204468 0.190677 ) Norm@50keV : 5.52053E-03 ( -0.000791552 0.000777669 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 67.35 using 59 bins. Reduced chi-squared = 1.18158 # Null hypothesis probability of 1.64e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 10.74 sec: 1.00087 ( -0.098182 0.09822 ) ph/cm2/s Energy fluence (15-150 keV) : 5.74029e-07 ( -6.56309e-08 6.68913e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.544 sec. to 4.192 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.13679 ( -0.86577 1.88387 ) Epeak [keV] : 25.1245 ( -24.1824 7.44396 ) Norm@50keV : 3.28811E-02 ( -0.0335534 0.564364 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 63.82 using 59 bins. Reduced chi-squared = 1.13964 # Null hypothesis probability of 2.21e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 10.74 sec: 0.963126 ( -0.105214 0.104544 ) 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 -0.108 sec. to 0.892 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.17302 ( -0.186274 0.175524 ) Norm@50keV : 2.10520E-02 ( -0.00289856 0.00285131 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 69.45 using 59 bins. Reduced chi-squared = 1.21842 # Null hypothesis probability of 1.25e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 3.43690 ( -0.37017 0.37024 ) ph/cm2/s Energy fluence (15-150 keV) : 1.97247e-07 ( -2.41976e-08 2.45063e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.108 sec. to 0.892 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.0711754 ( -1.08917 1.45728 ) Epeak [keV] : 34.6668 ( -5.4818 5.32156 ) Norm@50keV : 0.412678 ( -0.420179 3.20779 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 55.95 using 59 bins. Reduced chi-squared = 0.999107 # Null hypothesis probability of 4.77e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 3.34958 ( -0.36944 0.37055 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 8.848 sec. Hardness ratio (energy fluence ratio) = 0.776658437567
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 3.590439e-07 S(50-150 keV) = 2.1499263e-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 = -9.205829732229645E-01, IMY = -4.167005463225783E-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: -239.896000 -6.544000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 156.9907 42.6781 4.6 27.2 92.3 2.1664 2.6 ------ UNKNOWN 166.2179 28.7559 3.5 13.8 66.6 2.0178 3.3 ------ UNKNOWN 177.6817 -15.9416 2.1 39.9 -42.9 5.8973 5.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -6.544000 4.192000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 225.6007 47.4526 0.7 42.7 177.4 1.0926 15.3 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 108.604600 962.235100 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3998 35.5384 0.0 24.5 -176.1 1.5570 0.7 12.1 Her X-1 256.1016 11.6805 2.8 44.0 -150.5 19.8647 4.1 ------ UNKNOWN