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 Dec 18 16:27:35 EST 2024
Host Name: batproc1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger1267501
======================================================================
Trigger: 01267501 Segment: 000
BAT Trigger Time: 753176928.32 [s; MET]
Trigger Stop: 753176928.832 [s; MET]
UTC: 2024-11-13T07:48:13.793200 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 16.5765600663166 Dec: -22.667045457393 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.9
Image Trigger?: NO
Rate S/N Ratio: 18.7082869338697 [ if not an image trigger ]
Image S/N Ratio: 7.9
Analysis Position: [ source = BAT ]
RA: 16.5765600663166 Dec: -22.667045457393 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 16.5777959040528 Dec: -22.6590134019783 [deg; J2000]
{ 01h 06m 18.7s , -22d 39' 32.4" }
+/- 1.64947696143268 [arcmin] (estimated 90% radius based on SNR)
+/- 0.600593769751538 [arcmin] (formal 1-sigma fit error)
SNR: 14.880712681062
Angular difference between the analysis and refined position is 0.486757 arcmin
Partial Coding Fraction: 0.9375 [ including projection effects ]
Duration
T90: 1.87199985980988 +/- 0.474994699930438
Measured from: 0.0559999942779541
to: 1.92799985408783 [s; relative to TRIGTIME]
T50: 0.779999852180481 +/- 0.245079462703334
Measured from: 0.324000000953674
to: 1.10399985313416 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0200001001358032
to: 0.979999899864197 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.0200001001358032
to: 2.18799996376038 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.092254 0.084176 0.053339 0.021713
0.009351 0.009688 0.008206 0.006710 [error]
Peak 0.059094 0.065950 0.048633 0.007935
0.006536 0.006951 0.005974 0.004690 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 2.208 -0.020 2.188
T90 1.872 0.056 1.928
T50 0.780 0.324 1.104
Peak 1.000 -0.020 0.980
====== 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 -1.807 -0.238 0.227 - - - 6.27e-03 -8.96e-04 8.65e-04 50.930 57
CPL -2.309 -0.133 0.777 114.390 N/A N/A 3.55e-03 N/A N/A 49.710 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 -1.653 -0.209 0.202 - - - 1.09e-02 -1.34e-03 1.32e-03 45.060 57
CPL -1.649 -0.212 0.569 9999.090 -9999.080 -9999.090 1.09e-02 -6.80e-03 1.03e-02 45.060 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 2.36e-08 3.60e-08 4.11e-08 8.98e-08 1.28e-07 1.91e-07 erg/cm2
90%_error_low -4.20e-09 -4.17e-09 -8.10e-09 -3.18e-08 -1.82e-08 -4.04e-08 erg/cm2
90%_error_hi 4.33e-09 4.16e-09 8.15e-09 4.18e-08 1.86e-08 4.84e-08 erg/cm2
Peak flux PL 5.18e-01 4.76e-01 3.03e-01 2.96e-01 1.42e+00 1.59e+00 ph/cm2/s
90%_error_low -9.13e-02 -5.35e-02 -4.92e-02 -8.67e-02 -1.57e-01 -1.79e-01 ph/cm2/s
90%_error_hi 9.51e-02 5.33e-02 4.87e-02 1.06e-01 1.57e-01 1.80e-01 ph/cm2/s
Fluence CPL 2.28e-08 2.80e-08 4.07e-08 8.96e-08 1.12e-07 1.88e-07 erg/cm2
90%_error_low -4.81e-09 -5.95e-09 -2.61e-08 N/A -2.29e-08 -5.15e-08 erg/cm2
90%_error_hi 4.79e-09 6.85e-09 -5.95e-09 N/A 1.96e-08 5.13e-08 erg/cm2
Peak flux CPL 4.96e-01 3.41e-01 1.61e-01 1.27e-01 1.05e+00 1.12e+00 ph/cm2/s
90%_error_low -1.16e-01 -6.35e-02 -5.24e-02 -7.23e-02 -3.06e-01 -2.60e-01 ph/cm2/s
90%_error_hi 1.16e-01 9.59e-02 5.60e-02 5.32e-02 2.86e-01 3.12e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 16.5778 -22.6590 0.0129 12.9581 44.4324 0.2599419 14.881 TRIG_01267501 Foreground time interval of the image: -0.020 2.188 (delta_t = 2.208 [sec]) Background time interval of the image: -239.320 -0.020 (delta_t = 239.300 [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 -0.020 sec. to 2.188 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.80742 ( -0.237964 0.226591 ) Norm@50keV : 6.27370E-03 ( -0.000895979 0.000864851 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 50.93 using 59 bins. Reduced chi-squared = 0.893509 # Null hypothesis probability of 7.01e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 2.208 sec: 0.867048 ( -0.100758 0.100803 ) ph/cm2/s Energy fluence (15-150 keV) : 1.27511e-07 ( -1.8194e-08 1.85782e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.020 sec. to 2.188 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.30872 ( -0.132784 0.777236 ) Epeak [keV] : 114.390 ( ) Norm@50keV : 3.54649E-03 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 49.71 using 59 bins. Reduced chi-squared = 0.887679 # Null hypothesis probability of 7.10e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 2.208 sec: 0.692381 ( -0.148593 0.176054 ) ph/cm2/s Energy fluence (15-150 keV) : 1.12331e-07 ( -2.28771e-08 1.95795e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.020 sec. to 0.980 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.65293 ( -0.208507 0.201765 ) Norm@50keV : 1.08713E-02 ( -0.00134321 0.00131497 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 45.06 using 59 bins. Reduced chi-squared = 0.790526 # Null hypothesis probability of 8.74e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 1.42095 ( -0.15708 0.15722 ) ph/cm2/s Energy fluence (15-150 keV) : 1.01093e-07 ( -1.32535e-08 1.34451e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.020 sec. to 0.980 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.64896 ( -0.210783 0.570093 ) Epeak [keV] : 9999.09 ( -9999.32 -9999.33 ) Norm@50keV : 1.08955E-02 ( -0.00680552 0.0103005 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 45.06 using 59 bins. Reduced chi-squared = 0.804643 # Null hypothesis probability of 8.52e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 1.05186 ( -0.305792 0.28555 ) ph/cm2/s Energy fluence (15-150 keV) : 1.01503e-07 ( -1.47769e-08 1.39858e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 1.872 sec. Hardness ratio (energy fluence ratio) = 1.14282575734
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 5.962656e-08 S(50-150 keV) = 6.7886e-08
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 = 1.643081713956925E-01, IMY = -1.610843671840437E-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: -239.320000 -0.020000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 28.7962 -3.7142 3.4 32.2 77.5 2.1292 3.4 ------ UNKNOWN 9.9962 -38.9569 2.6 9.6 -54.7 1.3749 4.5 ------ UNKNOWN 49.2422 -51.2987 2.3 26.0 -159.9 1.5059 5.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.020000 2.188000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 25.4646 -20.4193 2.1 15.2 79.1 0.0984 5.4 ------ UNKNOWN 16.5778 -22.6590 0.8 13.0 44.4 0.2599 14.9 ------ UNKNOWN 336.8098 1.5721 2.3 55.1 4.6 0.3731 5.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 59.580600 311.951300 312.680000 362.860000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 356.0824 26.1464 2.8 52.7 26.4 62.8968 4.1 ------ UNKNOWN 343.8369 17.0664 3.3 51.0 8.0 30.9678 3.5 ------ UNKNOWN 336.8878 18.9100 3.5 56.8 3.5 54.7838 3.3 ------ UNKNOWN