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 Jan 19 13:58:27 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger370791
======================================================================
Trigger: 00370791 Segment: 000
BAT Trigger Time: 275694953.536 [s; MET]
Trigger Stop: 275694954.56 [s; MET]
UTC: 2009-09-26T21:55:48.416220 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 46.3178528437853 Dec: -39.0113731127945 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.74
Image Trigger?: NO
Rate S/N Ratio: 14.6969384566991 [ if not an image trigger ]
Image S/N Ratio: 6.74
Analysis Position: [ source = BAT ]
RA: 46.3178528437853 Dec: -39.0113731127945 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 46.3124822664893 Dec: -38.9970842177631 [deg; J2000]
{ 03h 05m 15.0s , -38d 59' 49.5" }
+/- 0.838705255882944 [arcmin] (estimated 90% radius based on SNR)
+/- 0.251014504303666 [arcmin] (formal 1-sigma fit error)
SNR: 39.1064018893157
Angular difference between the analysis and refined position is 0.893155 arcmin
Partial Coding Fraction: 0.265625 [ including projection effects ]
Duration
T90: 99.2839999198914 +/- 11.2994351566689
Measured from: -16.9359999895096
to: 82.3479999303818 [s; relative to TRIGTIME]
T50: 29.1279999613762 +/- 2.44140943779479
Measured from: -3.20800000429153
to: 25.9199999570847 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -1.31200003623962
to: -0.312000036239624 [s; relative to TRIGTIME]
Total Fluence
Measured from: -21.6119999885559
to: 130.339999973774 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.463953 4.469433 3.494782 0.610908
0.088319 0.096341 0.085921 0.069487 [error]
Peak 0.069238 0.145905 0.123211 0.044687
0.011114 0.013348 0.012193 0.009195 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 151.952 -21.612 130.340
T90 99.284 -16.936 82.348
T50 29.128 -3.208 25.920
Peak 1.000 -1.312 -0.312
====== 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 -1.505 N/A N/A - - - 5.23e-03 N/A N/A 121.110 57
CPL -0.516 -0.228 0.239 80.545 -6.341 9.009 1.52e-02 -3.22e-03 4.34e-03 56.770 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 -1.216 -0.166 0.169 - - - 2.68e-02 -2.67e-03 2.67e-03 45.660 57
CPL -0.886 -0.414 0.716 190.291 -190.291 -190.291 3.81e-02 -1.33e-02 4.05e-02 44.870 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 1.02e-06 1.87e-06 2.63e-06 7.79e-06 7.54e-06 1.33e-05 erg/cm2
90%_error_low N/A N/A N/A N/A N/A N/A erg/cm2
90%_error_hi N/A N/A N/A N/A N/A N/A erg/cm2
Peak flux PL 8.42e-01 1.00e+00 8.64e-01 1.27e+00 3.16e+00 3.98e+00 ph/cm2/s
90%_error_low -1.57e-01 -1.20e-01 -9.62e-02 -2.72e-01 -3.28e-01 -4.05e-01 ph/cm2/s
90%_error_hi 1.67e-01 1.19e-01 9.52e-02 3.14e-01 3.29e-01 4.09e-01 ph/cm2/s
Fluence CPL 8.17e-07 2.00e-06 2.84e-06 2.67e-06 7.12e-06 8.32e-06 erg/cm2
90%_error_low -6.41e-08 -6.77e-08 -1.03e-07 -4.91e-07 -2.38e-07 -5.34e-07 erg/cm2
90%_error_hi 6.54e-08 6.81e-08 1.04e-07 6.22e-07 2.38e-07 6.45e-07 erg/cm2
Peak flux CPL 7.78e-01 1.03e+00 9.01e-01 9.20e-01 3.12e+00 3.63e+00 ph/cm2/s
90%_error_low -1.95e-01 -1.30e-01 -1.18e-01 -4.09e-01 -3.35e-01 -5.48e-01 ph/cm2/s
90%_error_hi 2.00e-01 1.33e-01 1.22e-01 4.50e-01 3.35e-01 5.93e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 46.3125 -38.9971 0.0049 40.0827 144.2779 6.6672451 39.106 TRIG_00370791 Foreground time interval of the image: -21.612 10.365 (delta_t = 31.977 [sec]) Background time interval of the image: -542.035 -442.376 (delta_t = 99.659 [sec]) -239.536 -21.612 (delta_t = 217.924 [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 -21.612 sec. to 130.340 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.5052 ( ) Norm@50keV : 5.23010E-03 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 121.11 using 59 PHA bins. # Reduced chi-squared = 2.1248 for 57 degrees of freedom # Null hypothesis probability = 1.601540e-06 Photon flux (15-150 keV) in 152 sec: 0.653855 ( ) ph/cm2/s Energy fluence (15-150 keV) : 7.53622e-06 ( 0 0 ) ergs/cm2
Cutoff power-law model
Time interval is from -21.612 sec. to 130.340 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.516398 ( -0.227511 0.239312 ) Epeak [keV] : 80.5453 ( -6.34117 9.00894 ) Norm@50keV : 1.51859E-02 ( -0.00322385 0.00433624 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 56.77 using 59 PHA bins. # Reduced chi-squared = 1.014 for 56 degrees of freedom # Null hypothesis probability = 4.461669e-01 Photon flux (15-150 keV) in 152 sec: 0.617314 ( -0.020761 0.020831 ) ph/cm2/s Energy fluence (15-150 keV) : 7.12334e-06 ( -2.37556e-07 2.37772e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -1.312 sec. to -0.312 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.21632 ( -0.166149 0.168588 ) Norm@50keV : 2.68341E-02 ( -0.00266885 0.00266625 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 45.66 using 59 PHA bins. # Reduced chi-squared = 0.8010 for 57 degrees of freedom # Null hypothesis probability = 8.596015e-01 Photon flux (15-150 keV) in 1 sec: 3.15721 ( -0.32795 0.32872 ) ph/cm2/s Energy fluence (15-150 keV) : 2.71038e-07 ( -2.88459e-08 2.89335e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.312 sec. to -0.312 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.886271 ( -0.413867 0.715845 ) Epeak [keV] : 190.291 ( -190.291 -190.291 ) Norm@50keV : 3.80579E-02 ( -0.0133008 0.0405112 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 44.87 using 59 PHA bins. # Reduced chi-squared = 0.8013 for 56 degrees of freedom # Null hypothesis probability = 8.568479e-01 Photon flux (15-150 keV) in 1 sec: 3.12230 ( -0.33512 0.3354 ) ph/cm2/s Energy fluence (15-150 keV) : 2.67942e-07 ( -2.98965e-08 2.96971e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 99.284 sec. Hardness ratio (energy fluence ratio) = 1.42095386278
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 2.8161052e-06 S(50-150 keV) = 4.307344e-06
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 = -6.832285345832823E-01, IMY = -4.913492988858728E-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: -542.035390 -442.376000 -239.536000 -21.612000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 264.9804 -44.3459 15.7 49.7 -40.0 0.7022 0.7 11.9 4U 1735-44 275.9520 -30.3359 10.1 57.5 -22.0 1.1134 1.1 2.3 H1820-303 285.0407 -24.9186 19.1 58.7 -10.6 0.7004 0.6 0.3 HT1900.1-2455 0.7613 -27.7115 2.4 38.9 80.5 3.3344 4.8 ------ UNKNOWN 60.5203 -41.6207 2.5 43.5 160.2 1.8562 4.6 ------ UNKNOWN 91.3591 -38.4132 3.1 58.3 -175.6 4.3664 3.7 ------ UNKNOWN 248.6708 -57.4370 3.4 44.2 -61.5 3.6102 3.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -21.612000 10.364600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 264.7122 -44.3817 37.4 49.7 -40.2 0.0757 0.3 4.3 4U 1735-44 275.9877 -30.3570 3.0 57.5 -21.9 1.0239 3.9 3.3 H1820-303 285.1411 -25.0432 0.0 58.6 -10.6 -0.3663 -1.1 9.3 HT1900.1-2455 46.3125 -38.9971 0.3 40.1 144.3 6.6672 39.1 ------ UNKNOWN 63.4244 -42.4480 2.1 44.0 163.5 0.7993 5.5 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 77.164600 962.575700 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 24.0827 -44.0175 2.8 17.3 30.8 1.4511 4.1 ------ UNKNOWN 65.8489 4.5738 2.7 47.2 171.7 3.7543 4.2 ------ UNKNOWN 346.0628 -65.4431 2.7 42.9 -3.3 3.1123 4.3 ------ UNKNOWN