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 22 18:30:14 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger181126
======================================================================
Trigger: 00181126 Segment: 000
BAT Trigger Time: 161343552 [s; MET]
Trigger Stop: 161343680 [s; MET]
UTC: 2006-02-11T09:39:10.990840 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 58.4020233754094 Dec: 21.4858393231787 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.55
Image Trigger?: YES
Rate S/N Ratio: 0 [ if not an image trigger ]
Image S/N Ratio: 12.55
Analysis Position: [ source = BAT ]
RA: 58.4020233754094 Dec: 21.4858393231787 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 58.3854042843909 Dec: 21.495370349101 [deg; J2000]
{ 03h 53m 32.5s , +21d 29' 43.3" }
+/- 1.48946512039503 [arcmin] (estimated 90% radius based on SNR)
+/- 0.503852818142319 [arcmin] (formal 1-sigma fit error)
SNR: 17.2159972045707
Angular difference between the analysis and refined position is 1.089898 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 126.460000008345 +/- 9.55531266524824
Measured from: 54.0920000076294
to: 180.552000015974 [s; relative to TRIGTIME]
T50: 80.0480000078678 +/- 6.29694434260896
Measured from: 77.0640000104904
to: 157.112000018358 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 150.331999987364
to: 151.331999987364 [s; relative to TRIGTIME]
Total Fluence
Measured from: 47.83599999547
to: 194.208000004292 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.045637 1.225824 0.760373 0.028479
0.059282 0.061899 0.055932 0.053456 [error]
Peak 0.019205 0.017819 0.012028 0.002755
0.004996 0.005213 0.004723 0.004407 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 146.372 47.836 194.208
T90 126.460 54.092 180.552
T50 80.048 77.064 157.112
Peak 1.000 150.332 151.332
====== 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: CPL)
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 -1.748 -0.112 0.110 - - - 1.27e-03 -8.70e-05 8.62e-05 63.500 57
CPL -0.942 -0.467 0.526 58.706 -9.200 22.229 3.49e-03 -1.52e-03 3.19e-03 54.070 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 -1.876 -0.649 0.527 - - - 3.01e-03 -1.19e-03 1.07e-03 41.470 57
CPL -1.882 -1.377 0.418 9999.190 N/A N/A 3.01e-03 N/A N/A 41.470 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 2.99e-07 4.73e-07 5.63e-07 1.30e-06 1.71e-06 2.64e-06 erg/cm2
90%_error_low -2.78e-08 -2.85e-08 -5.25e-08 -2.34e-07 -1.22e-07 -2.87e-07 erg/cm2
90%_error_hi 2.84e-08 2.85e-08 5.30e-08 2.67e-07 1.23e-07 3.14e-07 erg/cm2
Peak flux PL 1.78e-01 1.44e-01 7.83e-02 6.25e-02 4.28e-01 4.63e-01 ph/cm2/s
90%_error_low -6.74e-02 -3.97e-02 -3.85e-02 -4.40e-02 -1.16e-01 -1.31e-01 ph/cm2/s
90%_error_hi 7.16e-02 3.92e-02 3.94e-02 7.98e-02 1.16e-01 1.35e-01 ph/cm2/s
Fluence CPL 2.70e-07 5.14e-07 5.58e-07 3.94e-07 1.58e-06 1.74e-06 erg/cm2
90%_error_low -3.27e-08 -3.68e-08 -6.02e-08 -1.80e-07 -1.37e-07 -2.29e-07 erg/cm2
90%_error_hi 3.30e-08 3.76e-08 5.92e-08 3.51e-07 1.42e-07 3.74e-07 erg/cm2
Peak flux CPL 1.81e-01 1.43e-01 7.71e-02 6.72e-02 4.28e-01 4.64e-01 ph/cm2/s
90%_error_low -7.15e-02 -3.90e-02 N/A -4.05e-02 -1.17e-01 -1.44e-01 ph/cm2/s
90%_error_hi 7.11e-02 4.92e-02 N/A 7.47e-02 1.15e-01 1.27e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 58.3854 21.4954 0.0111 5.5813 178.1746 1.6692151 17.216 TRIG_00181126 Foreground time interval of the image: 47.836 137.301 (delta_t = 89.465 [sec]) Background time interval of the image: -299.000 47.836 (delta_t = 346.836 [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 47.836 sec. to 194.208 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.74829 ( -0.112024 0.109978 ) Norm@50keV : 1.26840E-03 ( -8.70475e-05 8.62529e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 63.50 using 59 PHA bins. # Reduced chi-squared = 1.114 for 57 degrees of freedom # Null hypothesis probability = 2.582972e-01 Photon flux (15-150 keV) in 146.4 sec: 0.171409 ( -0.010405 0.010411 ) ph/cm2/s Energy fluence (15-150 keV) : 1.71388e-06 ( -1.21773e-07 1.23386e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 47.836 sec. to 194.208 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.941694 ( -0.467286 0.525705 ) Epeak [keV] : 58.7060 ( -9.19948 22.229 ) Norm@50keV : 3.48626E-03 ( -0.00151895 0.00319142 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 54.07 using 59 PHA bins. # Reduced chi-squared = 0.9656 for 56 degrees of freedom # Null hypothesis probability = 5.480847e-01 Photon flux (15-150 keV) in 146.4 sec: 0.164403 ( -0.011077 0.011084 ) ph/cm2/s Energy fluence (15-150 keV) : 1.57616e-06 ( -1.37289e-07 1.41953e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 150.332 sec. to 151.332 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.87576 ( -0.648504 0.527382 ) Norm@50keV : 3.01374E-03 ( -0.00118626 0.00106932 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 41.47 using 59 PHA bins. # Reduced chi-squared = 0.7275 for 57 degrees of freedom # Null hypothesis probability = 9.392718e-01 Photon flux (15-150 keV) in 1 sec: 0.428147 ( -0.116183 0.116244 ) ph/cm2/s Energy fluence (15-150 keV) : 2.77096e-08 ( -9.88499e-09 1.05623e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 150.332 sec. to 151.332 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.88191 ( -1.37713 0.417222 ) Epeak [keV] : 9999.19 ( ) Norm@50keV : 3.00628E-03 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 41.47 using 59 PHA bins. # Reduced chi-squared = 0.7405 for 56 degrees of freedom # Null hypothesis probability = 9.263613e-01 Photon flux (15-150 keV) in 1 sec: 0.428453 ( -0.116698 0.115125 ) ph/cm2/s Energy fluence (15-150 keV) : 2.6007e-08 ( -2.52813e-08 8.03382e-09 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 126.46 sec. Hardness ratio (energy fluence ratio) = 1.08465089508
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 7.846172e-07 S(50-150 keV) = 7.915509e-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 = -9.767117629792654E-02, IMY = -3.112763639287293E-03
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: -299.000000 47.836000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.6289 22.0144 0.2 24.0 100.9 15.3298 46.6 0.2 Crab 27.7907 57.3737 2.5 37.0 -22.1 1.5404 4.7 ------ UNKNOWN 48.2512 -31.3134 3.7 59.1 -166.1 4.9444 3.1 ------ UNKNOWN 15.4311 15.4231 3.4 40.9 -93.2 4.7262 3.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: 47.836000 137.300600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.4700 22.0105 58.8 23.9 101.0 -0.0275 -0.2 9.1 Crab 58.3854 21.4954 0.7 5.6 178.2 1.6692 17.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 165.300600 303.076800 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.6407 22.0138 0.4 23.4 95.9 5.7310 32.2 0.4 Crab 64.3616 52.2791 2.2 31.1 18.9 0.8427 5.1 ------ UNKNOWN 24.7429 69.7303 2.9 52.3 -2.2 1.4884 4.0 ------ UNKNOWN