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: Mon Jan 13 22:54:14 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger451757
======================================================================
Trigger: 00451757 Segment: 000
BAT Trigger Time: 324990150.912 [s; MET]
Trigger Stop: 324990151.936 [s; MET]
UTC: 2011-04-20T11:02:24.037860 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 2.16510709260475 Dec: -37.8550292612526 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.93
Image Trigger?: NO
Rate S/N Ratio: 12.6491106406735 [ if not an image trigger ]
Image S/N Ratio: 7.93
Analysis Position: [ source = BAT ]
RA: 2.16510709260475 Dec: -37.8550292612526 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 2.16392106610135 Dec: -37.8770094287737 [deg; J2000]
{ 00h 08m 39.3s , -37d 52' 37.2" }
+/- 0.84520773199824 [arcmin] (estimated 90% radius based on SNR)
+/- 0.317731189257129 [arcmin] (formal 1-sigma fit error)
SNR: 38.6773127603391
Angular difference between the analysis and refined position is 1.320006 arcmin
Partial Coding Fraction: 0.1503906 [ including projection effects ]
Duration
T90: 13.8679999709129 +/- 1.30256362054126
Measured from: 1.42799997329712
to: 15.2959999442101 [s; relative to TRIGTIME]
T50: 4.72799998521805 +/- 0.404850582176752
Measured from: 5.92799997329712
to: 10.6559999585152 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 8.04399996995926
to: 9.04399996995926 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.103999972343445
to: 21.8159999847412 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 4.135931 4.135400 2.100571 0.341742
0.095461 0.096117 0.078715 0.057984 [error]
Peak 0.441170 0.519792 0.393224 0.091834
0.026448 0.029003 0.024733 0.015954 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 21.920 -0.104 21.816
T90 13.868 1.428 15.296
T50 4.728 5.928 10.656
Peak 1.000 8.044 9.044
====== 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 -2.270 -0.066 0.065 - - - 3.09e-02 -1.09e-03 1.09e-03 42.920 57
CPL -1.986 -0.011 0.159 2.434 -1.901 -1.537 4.27e-02 -3.38e-03 2.49e-03 42.420 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 -1.797 -0.107 0.105 - - - 1.03e-01 -6.26e-03 6.23e-03 37.250 57
CPL -1.796 -0.107 0.149 9999.350 -9999.340 -9999.350 1.03e-01 -6.83e-02 -2.33e-02 37.250 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 1.79e-06 2.07e-06 1.71e-06 2.39e-06 6.43e-06 7.96e-06 erg/cm2
90%_error_low -1.00e-07 -6.76e-08 -8.40e-08 -2.41e-07 -2.06e-07 -3.19e-07 erg/cm2
90%_error_hi 1.02e-07 6.74e-08 8.40e-08 2.58e-07 2.06e-07 3.27e-07 erg/cm2
Peak flux PL 5.66e+00 4.78e+00 2.75e+00 2.35e+00 1.42e+01 1.55e+01 ph/cm2/s
90%_error_low -5.85e-01 -3.06e-01 -2.10e-01 -3.49e-01 -9.11e-01 -9.23e-01 ph/cm2/s
90%_error_hi 6.06e-01 3.04e-01 2.07e-01 3.80e-01 9.15e-01 9.24e-01 ph/cm2/s
Fluence CPL 1.68e-06 2.06e-06 1.73e-06 1.60e-06 6.40e-06 7.19e-06 erg/cm2
90%_error_low -1.07e-07 -2.73e-08 -7.40e-08 -2.00e-07 N/A -4.11e-07 erg/cm2
90%_error_hi 1.27e-07 1.08e-07 9.53e-08 3.01e-07 N/A 3.81e-07 erg/cm2
Peak flux CPL 5.57e+00 4.19e+00 2.18e+00 1.91e+00 1.27e+01 1.38e+01 ph/cm2/s
90%_error_low -6.65e-01 -3.74e-01 -2.86e-01 -2.09e-01 -1.02e+00 -1.84e+00 ph/cm2/s
90%_error_hi 5.26e-01 3.16e-01 2.57e-01 1.62e-01 9.02e-01 1.70e+00 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
2.1639 -37.8770 0.0050 50.1980 -34.0831 8.9135016 38.677 TRIG_00451757
Foreground time interval of the image:
-0.104 10.989 (delta_t = 11.093 [sec])
Background time interval of the image:
-239.912 -0.104 (delta_t = 239.808 [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 -0.104 sec. to 21.816 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.27024 ( -0.0658492 0.0648655 ) Norm@50keV : 3.08648E-02 ( -0.00109266 0.0010864 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 42.92 using 59 PHA bins. # Reduced chi-squared = 0.7530 for 57 degrees of freedom # Null hypothesis probability = 9.165109e-01 Photon flux (15-150 keV) in 21.92 sec: 5.30663 ( -0.19898 0.20041 ) ph/cm2/s Energy fluence (15-150 keV) : 6.43251e-06 ( -2.05774e-07 2.05845e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.104 sec. to 21.816 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.99632 ( -0.00088396 0.169291 ) Epeak [keV] : 0.674262 ( -0.140623 0.223427 ) Norm@50keV : 4.20776E-02 ( -0.00281458 0.00305841 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 42.31 using 59 PHA bins. # Reduced chi-squared = 0.7556 for 56 degrees of freedom # Null hypothesis probability = 9.118960e-01 Photon flux (15-150 keV) in 21.92 sec: 5.14952 ( -0.15959 0.18094 ) ph/cm2/s Energy fluence (15-150 keV) : 6.39957e-06 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 8.044 sec. to 9.044 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.7972 ( -0.106893 0.105164 ) Norm@50keV : 0.103216 ( -0.00625877 0.00623383 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 37.25 using 59 PHA bins. # Reduced chi-squared = 0.6534 for 57 degrees of freedom # Null hypothesis probability = 9.801441e-01 Photon flux (15-150 keV) in 1 sec: 14.2082 ( -0.9114 0.9146 ) ph/cm2/s Energy fluence (15-150 keV) : 9.50452e-07 ( -5.84209e-08 5.85453e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.044 sec. to 9.044 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.29932 ( -0.107408 0.149155 ) Epeak [keV] : 116.169 ( -9999.35 -9999.36 ) Norm@50keV : 5.77570E-02 ( -0.0226602 0.0223046 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 36.69 using 59 PHA bins. # Reduced chi-squared = 0.6552 for 56 degrees of freedom # Null hypothesis probability = 9.785692e-01 Photon flux (15-150 keV) in 1 sec: 12.7287 ( -1.0218 0.9025 ) ph/cm2/s Energy fluence (15-150 keV) : 9.52752e-07 ( -7.44174e-08 6.98344e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 13.868 sec. Hardness ratio (energy fluence ratio) = 0.829200940582
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 3.856438e-06 S(50-150 keV) = 2.5760906e-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 = 9.939953859145266E-01, IMY = 6.725578022923394E-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: -239.912000 -0.104000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 268.3554 -1.4339 3.5 43.2 129.1 2.7231 3.3 1.4 SW J1753.5-0127 270.2372 -25.0575 8.8 36.6 93.2 0.7962 1.3 2.9 GX 5-1 270.3738 -25.8568 12.0 36.6 91.9 0.5926 1.0 7.8 GRS 1758-258 274.0373 -13.9885 2.0 33.8 112.8 2.2181 5.8 3.4 GX 17+2 276.1194 -30.4774 0.0 32.3 82.3 0.6564 1.6 12.0 H1820-303 285.0231 -24.8921 3.5 23.3 89.9 0.8799 3.3 1.8 HT1900.1-2455 288.8054 10.9494 1.3 35.2 165.1 2.5155 8.9 0.5 GRS 1915+105 299.6070 35.1648 2.1 53.9 -168.3 3.2537 5.6 2.4 Cyg X-1 308.2266 40.8413 13.3 58.9 -159.5 1.4504 0.9 8.5 Cyg X-3 316.6725 5.7813 3.2 25.0 -140.5 0.7255 3.6 ------ UNKNOWN 339.5783 12.6187 3.3 43.0 -112.1 3.5345 3.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.104000 10.988590 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 268.2247 -1.3754 0.0 43.4 129.1 -0.3188 -2.1 9.8 SW J1753.5-0127 270.1594 -25.2147 6.0 36.7 92.9 -0.2157 -1.9 10.6 GX 5-1 270.4015 -25.8395 18.2 36.5 91.9 0.0709 0.6 7.9 GRS 1758-258 273.9532 -14.1836 13.4 33.9 112.5 0.0732 0.9 9.3 GX 17+2 275.9504 -30.3519 59.8 32.4 82.6 -0.0148 -0.2 1.6 H1820-303 285.1589 -25.0372 6.0 23.2 89.5 -0.1096 -1.9 9.7 HT1900.1-2455 288.8043 10.7873 4.3 35.0 165.0 0.1598 2.7 9.5 GRS 1915+105 299.6196 35.3416 3.3 54.1 -168.3 0.3940 3.5 8.5 Cyg X-1 308.0616 40.9435 12.7 59.0 -159.6 -0.2166 -0.9 2.3 Cyg X-3 292.6422 -36.1985 2.7 23.2 56.4 0.2168 4.3 ------ UNKNOWN 306.7288 -0.1912 2.1 18.0 -166.3 0.2779 5.6 ------ UNKNOWN 314.4515 5.8463 2.7 24.5 -145.7 0.2386 4.3 ------ UNKNOWN 352.4674 -34.4243 2.7 41.9 -36.9 0.4733 4.3 ------ UNKNOWN 324.9207 14.9785 2.6 36.5 -132.4 0.4296 4.5 ------ UNKNOWN 2.1639 -37.8770 0.3 50.2 -34.1 8.9136 38.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 76.788600 962.158300 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 306.4456 -49.4310 2.2 40.9 113.9 9.8157 5.3 ------ UNKNOWN 68.4914 -43.3005 3.9 49.3 -2.7 2.9751 3.0 ------ UNKNOWN 50.1896 -13.2184 4.1 49.1 -48.0 7.1081 2.8 ------ UNKNOWN