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 20:01:13 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger156838
======================================================================
Trigger: 00156838 Segment: 000
BAT Trigger Time: 149331873.376 [s; MET]
Trigger Stop: 149331873.44 [s; MET]
UTC: 2005-09-25T09:04:33.628160 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 303.445191270095 Dec: 34.3345869373457 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 12.32
Image Trigger?: NO
Rate S/N Ratio: 32.3419232575925 [ if not an image trigger ]
Image S/N Ratio: 12.32
Analysis Position: [ source = BAT ]
RA: 303.445191270095 Dec: 34.3345869373457 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 303.487102165543 Dec: 34.3294762681033 [deg; J2000]
{ 20h 13m 56.9s , +34d 19' 46.1" }
+/- 1.51530577149535 [arcmin] (estimated 90% radius based on SNR)
+/- 0.783298449210249 [arcmin] (formal 1-sigma fit error)
SNR: 16.7981262463985
Angular difference between the analysis and refined position is 2.099077 arcmin
Partial Coding Fraction: 0.4140625 [ including projection effects ]
Duration
T90: 0.0920000076293945 +/- 0.0144222095322683
Measured from: -0.0319999754428864
to: 0.0600000321865082 [s; relative to TRIGTIME]
T50: 0.0439999997615814 +/- 0.0113137103534657
Measured from: -0.0039999783039093
to: 0.0400000214576721 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.48199999332428
to: 0.51800000667572 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.035999983549118
to: 0.0680000185966492 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.031026 0.051931 0.047176 0.006682
0.003937 0.004970 0.004791 0.002907 [error]
Peak 0.042505 0.069117 0.047615 0.003784
0.008807 0.009386 0.008560 0.006822 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 0.104 -0.036 0.068
T90 0.092 -0.032 0.060
T50 0.044 -0.004 0.040
Peak 1.000 -0.482 0.518
====== 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: N/A)
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 -1.695 -0.166 0.158 - - - 7.75e-02 -9.12e-03 9.06e-03 87.310 57
CPL 0.111 -0.804 0.945 63.800 -8.012 11.939 5.75e-01 -3.33e-01 9.89e-01 70.770 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 -1.733 -0.268 0.255 - - - 1.11e-02 -1.98e-03 1.96e-03 49.690 57
CPL -0.086 -1.182 1.607 55.054 -11.400 27.086 8.19e-02 -8.19e-02 4.89e-01 43.460 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 1.24e-08 2.02e-08 2.49e-08 6.09e-08 7.47e-08 1.18e-07 erg/cm2
90%_error_low -1.98e-09 -2.31e-09 -3.62e-09 -1.56e-08 -9.07e-09 -1.98e-08 erg/cm2
90%_error_hi 2.05e-09 2.30e-09 3.58e-09 1.80e-08 9.09e-09 2.14e-08 erg/cm2
Peak flux PL 5.70e-01 5.00e-01 3.01e-01 2.73e-01 1.49e+00 1.64e+00 ph/cm2/s
90%_error_low -1.36e-01 -8.38e-02 -6.67e-02 -1.01e-01 -2.48e-01 -2.72e-01 ph/cm2/s
90%_error_hi 1.44e-01 8.36e-02 6.67e-02 1.28e-01 2.48e-01 2.73e-01 ph/cm2/s
Fluence CPL N/A N/A N/A N/A N/A N/A erg/cm2
90%_error_low -1.98e-09 -2.31e-09 -3.62e-09 -1.56e-08 -9.07e-09 -1.98e-08 erg/cm2
90%_error_hi 2.05e-09 2.30e-09 3.58e-09 1.80e-08 9.09e-09 2.14e-08 erg/cm2
Peak flux CPL 4.45e-01 5.91e-01 3.33e-01 6.72e-02 1.42e+00 1.44e+00 ph/cm2/s
90%_error_low -1.59e-01 -1.08e-01 -8.50e-02 -6.72e-02 -2.51e-01 -2.57e-01 ph/cm2/s
90%_error_hi 1.68e-01 1.14e-01 8.43e-02 1.14e-01 2.52e-01 2.65e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 303.4871 34.3295 0.0114 44.9956 -15.7064 0.1468028 16.798 TRIG_00156838 Foreground time interval of the image: -0.036 0.068 (delta_t = 0.104 [sec]) Background time interval of the image: -299.376 -0.036 (delta_t = 299.340 [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 -0.036 sec. to 0.068 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.69462 ( -0.165705 0.157896 ) Norm@50keV : 7.75132E-02 ( -0.00912239 0.00906176 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 87.31 using 59 PHA bins. # Reduced chi-squared = 1.532 for 57 degrees of freedom # Null hypothesis probability = 6.023477e-03 Photon flux (15-150 keV) in 0.104 sec: 10.2756 ( -1.17795 1.1792 ) ph/cm2/s Energy fluence (15-150 keV) : 7.4685e-08 ( -9.06695e-09 9.08593e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.036 sec. to 0.068 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: 0.110959 ( -0.804279 0.945165 ) Epeak [keV] : 63.7997 ( -8.01271 11.9384 ) Norm@50keV : 0.575363 ( -0.332745 0.989031 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 70.77 using 59 PHA bins. # Reduced chi-squared = 1.264 for 56 degrees of freedom # Null hypothesis probability = 8.842928e-02 Photon flux (15-150 keV) in 0.104 sec: ( ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.482 sec. to 0.518 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.73306 ( -0.268223 0.254822 ) Norm@50keV : 1.10761E-02 ( -0.00198423 0.00195628 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 49.69 using 59 PHA bins. # Reduced chi-squared = 0.8717 for 57 degrees of freedom # Null hypothesis probability = 7.432809e-01 Photon flux (15-150 keV) in 1 sec: 1.48846 ( -0.2479 0.24832 ) ph/cm2/s Energy fluence (15-150 keV) : 1.02334e-07 ( -1.87217e-08 1.89993e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.482 sec. to 0.518 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.0856687 ( -1.18194 1.60714 ) Epeak [keV] : 55.0537 ( -11.4004 27.0858 ) Norm@50keV : 8.18885E-02 ( -0.0818874 0.488712 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 43.46 using 59 PHA bins. # Reduced chi-squared = 0.7761 for 56 degrees of freedom # Null hypothesis probability = 8.892872e-01 Photon flux (15-150 keV) in 1 sec: 1.42485 ( -0.25078 0.25191 ) ph/cm2/s Energy fluence (15-150 keV) : 9.44735e-08 ( -1.86838e-08 1.96093e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = N/A sec. Hardness ratio (energy fluence ratio) = N/A
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = N/A S(50-150 keV) = N/A
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 = 9.625137830726542E-01, IMY = 2.706669988381329E-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: -299.376000 -0.036000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 275.7787 -30.4459 9.9 44.4 -124.6 -0.8136 -1.2 8.9 H1820-303 285.0650 -24.9642 7.1 34.8 -121.3 0.5215 1.6 3.1 HT1900.1-2455 288.9102 11.0917 3.7 34.5 -55.0 0.9664 3.2 11.0 GRS 1915+105 299.5878 35.2084 0.4 47.0 -19.4 10.9058 29.2 0.4 Cyg X-1 308.2357 40.8451 57.1 50.3 -8.4 0.0925 0.2 8.6 Cyg X-3 326.1686 38.3077 3.8 47.7 9.9 1.3954 3.1 0.8 Cyg X-2 327.4683 40.5951 2.5 50.2 10.5 2.6116 4.6 ------ UNKNOWN 319.6869 48.3236 2.9 57.1 2.4 4.4707 3.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.036000 0.068000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 276.0435 -30.3004 4.5 44.2 -124.5 0.0347 2.6 7.3 H1820-303 285.0385 -25.0143 9.3 34.8 -121.4 0.0092 1.2 5.6 HT1900.1-2455 288.9379 10.8669 12.2 34.4 -55.3 0.0061 0.9 9.5 GRS 1915+105 299.7223 35.1844 12.8 46.9 -19.3 0.0084 0.9 6.6 Cyg X-1 307.9814 40.9475 4.2 50.4 -8.6 0.0304 2.7 5.8 Cyg X-3 326.0377 38.3722 6.8 47.8 9.7 -0.0202 -1.7 7.0 Cyg X-2 354.4076 -10.4088 2.2 36.6 96.3 0.0531 5.2 ------ UNKNOWN 303.4871 34.3295 0.7 45.0 -15.7 0.1468 16.8 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 75.124600 176.724600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.3055 35.2023 0.0 40.0 -92.3 0.1390 0.3 11.2 Her X-1 268.2516 -1.3613 31.1 48.6 -147.8 -0.0995 -0.4 8.9 SW J1753.5-0127 274.0226 -14.0449 9.5 55.9 -162.9 0.4417 1.2 1.1 GX 17+2 288.7702 11.1049 367.0 26.8 -164.5 0.0036 0.0 9.7 GRS 1915+105 299.5831 35.2012 0.3 3.3 -92.1 3.9193 40.5 0.4 Cyg X-1 308.1393 40.9623 2.2 7.6 9.6 0.5074 5.2 1.4 Cyg X-3 326.0795 38.3577 4.8 18.6 52.9 0.2752 2.4 4.8 Cyg X-2 241.7101 61.4995 2.3 47.0 -53.2 2.5103 5.0 ------ UNKNOWN