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 13:21:26 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger373871
======================================================================
Trigger: 00373871 Segment: 000
BAT Trigger Time: 278255495.36 [s; MET]
Trigger Stop: 278255496.384 [s; MET]
UTC: 2009-10-26T13:11:30.155080 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 276.583106903892 Dec: -86.1214064707332 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.08
Image Trigger?: NO
Rate S/N Ratio: 25.9422435421457 [ if not an image trigger ]
Image S/N Ratio: 12.08
Analysis Position: [ source = BAT ]
RA: 276.583106903892 Dec: -86.1214064707332 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 276.645550071726 Dec: -86.1139251883559 [deg; J2000]
{ 18h 26m 34.9s , -86d 06' 50.1" }
+/- 1.02624251401057 [arcmin] (estimated 90% radius based on SNR)
+/- 0.479519881838883 [arcmin] (formal 1-sigma fit error)
SNR: 29.3121009941847
Angular difference between the analysis and refined position is 0.515597 arcmin
Partial Coding Fraction: 0.3632812 [ including projection effects ]
Duration
T90: 174 +/- 72.5275809606249
Measured from: -2.36000001430511
to: 171.639999985695 [s; relative to TRIGTIME]
T50: 36 +/- 11.0453610171873
Measured from: 0.639999985694885
to: 36.6399999856949 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.360000014305115
to: 0.639999985694885 [s; relative to TRIGTIME]
Total Fluence
Measured from: -4.36000001430511
to: 215.639999985695 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.098805 1.344951 0.814860 0.316382
0.084433 0.087657 0.079217 0.072386 [error]
Peak 0.059479 0.098433 0.091531 0.029370
0.009494 0.010486 0.010292 0.008571 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 220.000 -4.360 215.640
T90 174.000 -2.360 171.640
T50 36.000 0.640 36.640
Peak 1.000 -0.360 0.640
====== 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 -1.702 -0.139 0.137 - - - 9.98e-04 -8.44e-05 8.34e-05 65.870 57
CPL -1.608 -0.525 0.587 183.865 -164.233 -183.865 1.13e-03 -2.32e-04 1.26e-03 65.780 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 -1.219 -0.205 0.207 - - - 1.85e-02 -2.13e-03 2.13e-03 67.180 57
CPL -1.216 -0.204 0.686 9999.320 -9999.320 -9999.320 1.86e-02 -1.86e-02 2.01e-02 67.180 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 3.39e-07 5.50e-07 6.77e-07 1.64e-06 2.03e-06 3.21e-06 erg/cm2
90%_error_low -4.00e-08 -4.18e-08 -7.74e-08 -3.58e-07 -1.80e-07 -4.35e-07 erg/cm2
90%_error_hi 4.10e-08 4.18e-08 7.78e-08 4.22e-07 1.83e-07 4.87e-07 erg/cm2
Peak flux PL 5.82e-01 6.92e-01 5.95e-01 8.71e-01 2.18e+00 2.74e+00 ph/cm2/s
90%_error_low -1.24e-01 -9.29e-02 -8.23e-02 -2.32e-01 -2.56e-01 -3.35e-01 ph/cm2/s
90%_error_hi 1.32e-01 9.12e-02 8.11e-02 2.82e-01 2.56e-01 3.43e-01 ph/cm2/s
Fluence CPL 3.36e-07 5.57e-07 6.76e-07 1.37e-06 2.01e-06 2.94e-06 erg/cm2
90%_error_low -4.39e-08 -4.76e-08 -7.98e-08 -8.63e-07 -2.24e-07 -8.96e-07 erg/cm2
90%_error_hi 4.23e-08 5.68e-08 7.90e-08 3.58e-07 2.01e-07 7.28e-07 erg/cm2
Peak flux CPL 5.81e-01 6.91e-01 5.94e-01 8.66e-01 2.18e+00 2.76e+00 ph/cm2/s
90%_error_low N/A N/A N/A N/A N/A -5.66e-01 ph/cm2/s
90%_error_hi N/A N/A N/A N/A N/A 3.24e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 276.6456 -86.1139 0.0066 33.0585 -110.7727 2.2709497 29.312 TRIG_00373871 Foreground time interval of the image: -4.360 14.341 (delta_t = 18.701 [sec]) Background time interval of the image: -239.360 -4.360 (delta_t = 235.000 [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 -4.360 sec. to 215.640 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.70162 ( -0.139475 0.137286 ) Norm@50keV : 9.97517E-04 ( -8.43549e-05 8.33689e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 65.87 using 59 PHA bins. # Reduced chi-squared = 1.156 for 57 degrees of freedom # Null hypothesis probability = 1.968378e-01 Photon flux (15-150 keV) in 220 sec: 0.132562 ( -0.0101 0.010106 ) ph/cm2/s Energy fluence (15-150 keV) : 2.0319e-06 ( -1.80023e-07 1.82531e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.360 sec. to 215.640 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.6078 ( -0.523758 0.587809 ) Epeak [keV] : 183.865 ( -166.783 -186.415 ) Norm@50keV : 1.12609E-03 ( -0.000229518 0.00125857 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 65.78 using 59 PHA bins. # Reduced chi-squared = 1.175 for 56 degrees of freedom # Null hypothesis probability = 1.742170e-01 Photon flux (15-150 keV) in 220 sec: 0.132021 ( -0.010572 0.010474 ) ph/cm2/s Energy fluence (15-150 keV) : 2.0092e-06 ( -2.23727e-07 2.00753e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.360 sec. to 0.640 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.2186 ( -0.20473 0.207073 ) Norm@50keV : 1.84948E-02 ( -0.00213104 0.00212925 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 67.18 using 59 PHA bins. # Reduced chi-squared = 1.179 for 57 degrees of freedom # Null hypothesis probability = 1.676401e-01 Photon flux (15-150 keV) in 1 sec: 2.17678 ( -0.25567 0.25613 ) ph/cm2/s Energy fluence (15-150 keV) : 1.8669e-07 ( -2.4296e-08 2.45178e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.360 sec. to 0.640 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.2164 ( -0.20421 0.685753 ) Epeak [keV] : 9999.32 ( -9999.36 -9999.36 ) Norm@50keV : 1.85693E-02 ( -0.0185808 0.02011 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 67.18 using 59 PHA bins. # Reduced chi-squared = 1.200 for 56 degrees of freedom # Null hypothesis probability = 1.455626e-01 Photon flux (15-150 keV) in 1 sec: 2.17643 ( ) ph/cm2/s Energy fluence (15-150 keV) : 1.8731e-07 ( -2.69264e-08 2.09904e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 174.0 sec. Hardness ratio (energy fluence ratio) = 1.22978736161
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 8.891082e-07 S(50-150 keV) = 1.1428186e-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 = -2.308345543989691E-01, IMY = 6.085509223324870E-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: -239.360000 -4.360000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 341.6130 -10.0382 2.1 47.7 43.2 4.4151 5.5 ------ UNKNOWN 81.1869 -40.9174 2.6 54.6 174.7 3.2246 4.4 ------ UNKNOWN 102.2918 -48.0342 3.2 59.0 -166.2 4.4145 3.6 ------ UNKNOWN 239.3741 -76.3635 3.9 41.3 -99.1 3.0143 3.0 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -4.360000 14.340600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 26.6303 -22.8667 2.4 40.4 109.0 0.8427 4.9 ------ UNKNOWN 276.6455 -86.1139 0.4 33.1 -110.8 2.2713 29.3 ------ UNKNOWN 135.3656 -70.3241 2.3 50.0 -134.3 1.1849 5.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 67.940590 962.667500 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5222 -40.4053 17.3 52.7 -166.4 -1.0567 -0.7 9.0 Vela X-1 170.2961 -60.6340 1.3 30.7 -136.0 5.6731 9.1 0.9 Cen X-3 186.5731 -62.7321 3.9 27.5 -120.9 1.6648 2.9 3.2 GX 301-2 255.8752 -37.8070 6.9 48.6 -45.3 4.2770 1.7 5.7 4U 1700-377 256.7221 -36.4122 8.7 50.0 -44.3 3.2917 1.3 13.9 GX 349+2 264.7131 -44.5197 7.3 41.7 -36.2 1.2819 1.6 4.4 4U 1735-44 276.0344 -30.4063 7.7 55.7 -24.0 -2.6008 -1.5 6.1 H1820-303 263.0920 -33.9157 11.1 52.3 -37.6 1.9906 1.0 7.1 GX 354-0 98.3041 -44.4136 3.0 49.5 158.2 6.3993 3.8 ------ UNKNOWN 315.7556 -39.9246 2.7 47.1 18.0 4.7697 4.2 ------ UNKNOWN 123.5801 -55.9437 2.5 37.6 -178.7 3.1163 4.7 ------ UNKNOWN 293.8888 -30.8785 3.0 55.4 -5.4 5.8539 3.8 ------ UNKNOWN 289.9354 -28.7662 3.3 57.5 -9.5 7.6639 3.5 ------ UNKNOWN 215.4213 -62.7563 3.0 25.6 -91.7 2.3990 3.9 ------ UNKNOWN 271.7431 -29.8700 3.3 56.3 -28.5 7.1551 3.5 ------ UNKNOWN 199.3474 -50.8392 4.2 38.5 -105.4 4.2161 2.8 ------ UNKNOWN