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 22:45:44 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger324744
======================================================================
Trigger: 00324744 Segment: 000
BAT Trigger Time: 243129773.056 [s; MET]
Trigger Stop: 243129777.152 [s; MET]
UTC: 2008-09-15T00:02:49.957760 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 18.0040672407145 Dec: -76.0144041971717 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.13
Image Trigger?: NO
Rate S/N Ratio: 8.18535277187245 [ if not an image trigger ]
Image S/N Ratio: 7.13
Analysis Position: [ source = BAT ]
RA: 18.0040672407145 Dec: -76.0144041971717 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 17.8853408690745 Dec: -76.0443829252976 [deg; J2000]
{ 01h 11m 32.5s , -76d 02' 39.8" }
+/- 2.43155402306048 [arcmin] (estimated 90% radius based on SNR)
+/- 1.52620369750692 [arcmin] (formal 1-sigma fit error)
SNR: 8.54782520983947
Angular difference between the analysis and refined position is 2.488600 arcmin
Partial Coding Fraction: 0.890625 [ including projection effects ]
Duration
T90: 26.2879999577999 +/- 3.89810207565097
Measured from: -0.815999984741211
to: 25.4719999730587 [s; relative to TRIGTIME]
T50: 10.6079999804497 +/- 9.8563247074382
Measured from: 3.12000000476837
to: 13.727999985218 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 3.04399999976158
to: 4.04399999976158 [s; relative to TRIGTIME]
Total Fluence
Measured from: -2.67199999094009
to: 26.7199999988079 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.146887 0.201004 0.097420 0.021154
0.028435 0.029328 0.026237 0.024173 [error]
Peak 0.019211 0.015941 0.016887 -0.000338
0.005280 0.005457 0.004887 0.004639 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 29.392 -2.672 26.720
T90 26.288 -0.816 25.472
T50 10.608 3.120 13.728
Peak 1.000 3.044 4.044
====== 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 -1.582 -0.312 0.306 - - - 1.06e-03 -2.02e-04 1.98e-04 52.620 57
CPL -1.288 -0.596 2.408 103.087 -103.087 -103.087 1.56e-03 -9.97e-04 4.36e-02 52.500 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 -1.488 -0.567 0.540 - - - 3.72e-03 -1.12e-03 1.07e-03 55.670 57
CPL -1.488 -2.094 1.270 9999.340 N/A N/A 3.72e-03 N/A N/A 55.670 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 4.28e-08 7.49e-08 1.00e-07 2.74e-07 2.91e-07 4.91e-07 erg/cm2
90%_error_low -1.15e-08 -1.33e-08 -2.51e-08 -1.19e-07 -5.94e-08 -1.46e-07 erg/cm2
90%_error_hi 1.20e-08 1.32e-08 2.53e-08 1.71e-07 6.10e-08 1.89e-07 erg/cm2
Peak flux PL 1.51e-01 1.53e-01 1.09e-01 1.24e-01 4.62e-01 5.38e-01 ph/cm2/s
90%_error_low -6.94e-02 -4.61e-02 -4.26e-02 -7.70e-02 -1.29e-01 -1.53e-01 ph/cm2/s
90%_error_hi 7.89e-02 4.44e-02 4.10e-02 1.30e-01 1.29e-01 1.58e-01 ph/cm2/s
Fluence CPL 4.19e-08 7.79e-08 9.93e-08 1.57e-07 2.80e-07 3.72e-07 erg/cm2
90%_error_low -1.26e-08 -1.60e-08 N/A N/A -8.73e-08 -1.78e-07 erg/cm2
90%_error_hi 1.27e-08 2.32e-08 N/A N/A 7.04e-08 1.73e-07 erg/cm2
Peak flux CPL 1.54e-01 1.53e-01 1.08e-01 1.38e-01 4.63e-01 5.41e-01 ph/cm2/s
90%_error_low N/A -4.59e-02 N/A N/A N/A -1.83e-01 ph/cm2/s
90%_error_hi N/A 4.79e-02 N/A N/A N/A 1.41e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 17.8853 -76.0444 0.0224 27.3669 -170.2244 0.4767006 8.548 TRIG_00324744 Foreground time interval of the image: -2.672 26.720 (delta_t = 29.392 [sec]) Background time interval of the image: -239.056 -2.672 (delta_t = 236.384 [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 -2.672 sec. to 26.720 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.58218 ( -0.311857 0.306052 ) Norm@50keV : 1.05660E-03 ( -0.000202089 0.000198044 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 52.62 using 59 PHA bins. # Reduced chi-squared = 0.9231 for 57 degrees of freedom # Null hypothesis probability = 6.400448e-01 Photon flux (15-150 keV) in 29.39 sec: 0.135044 ( -0.023701 0.023715 ) ph/cm2/s Energy fluence (15-150 keV) : 2.91112e-07 ( -5.93831e-08 6.10398e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.672 sec. to 26.720 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.28835 ( -0.591006 2.41299 ) Epeak [keV] : 103.087 ( -104.994 -104.994 ) Norm@50keV : 1.56179E-03 ( -0.000977103 0.043594 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 52.50 using 59 PHA bins. # Reduced chi-squared = 0.9376 for 56 degrees of freedom # Null hypothesis probability = 6.080142e-01 Photon flux (15-150 keV) in 29.39 sec: 0.133551 ( -0.025491 0.024673 ) ph/cm2/s Energy fluence (15-150 keV) : 2.79937e-07 ( -8.72774e-08 7.04196e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 3.044 sec. to 4.044 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.48762 ( -0.566544 0.539899 ) Norm@50keV : 3.71588E-03 ( -0.00112055 0.00106972 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 55.67 using 59 PHA bins. # Reduced chi-squared = 0.9766 for 57 degrees of freedom # Null hypothesis probability = 5.252393e-01 Photon flux (15-150 keV) in 1 sec: 0.462371 ( -0.128803 0.129275 ) ph/cm2/s Energy fluence (15-150 keV) : 3.53281e-08 ( -1.14577e-08 1.18489e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.044 sec. to 4.044 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -3.25321 ( -0.327119 3.03714 ) Epeak [keV] : 341.311 ( ) Norm@50keV : 5.00533E-04 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 54.72 using 59 PHA bins. # Reduced chi-squared = 0.9771 for 56 degrees of freedom # Null hypothesis probability = 5.234678e-01 Photon flux (15-150 keV) in 1 sec: 0.463474 ( ) ph/cm2/s Energy fluence (15-150 keV) : 3.55558e-08 ( -7.69844e-09 6.46555e-09 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 26.288 sec. Hardness ratio (energy fluence ratio) = 1.33597979021
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 1.1768593e-07 S(50-150 keV) = 1.7342539e-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 = -5.101016289983309E-01, IMY = 8.788627582560590E-02
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: -239.056000 -2.672000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 256.0552 -37.8700 5.8 37.0 -29.5 0.5644 2.0 3.6 4U 1700-377 256.4260 -36.4160 26.7 38.0 -27.8 0.1273 0.4 0.6 GX 349+2 263.1257 -24.7301 4.3 45.7 -11.9 0.9522 2.7 6.4 GX 1+4 264.6800 -44.3862 6.0 27.9 -26.4 0.3978 1.9 4.7 4U 1735-44 270.3978 -25.0392 5.2 42.9 -3.3 0.7618 2.2 6.6 GX 5-1 270.2549 -25.6356 3.9 42.4 -3.8 0.9489 2.9 6.9 GRS 1758-258 273.9867 -14.0274 12.5 52.4 5.6 0.5683 0.9 1.2 GX 17+2 275.9099 -30.3855 4.3 36.2 1.0 0.7152 2.7 1.4 H1820-303 284.9284 -24.8028 9.1 39.4 16.0 -0.4066 -1.3 9.2 HT1900.1-2455 262.9855 -33.8376 2.2 37.6 -18.1 1.3515 5.3 0.3 GX 354-0 292.1667 -18.6176 2.7 44.5 27.4 2.0414 4.2 ------ UNKNOWN 281.0967 -12.1761 2.0 52.5 14.7 4.6759 5.9 ------ UNKNOWN 273.2337 -10.0276 2.5 56.4 6.1 5.4369 4.6 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -2.672000 26.720000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 256.0197 -37.7130 4.7 37.1 -29.3 0.1892 2.5 8.0 4U 1700-377 256.4524 -36.4558 15.0 38.0 -27.8 0.0628 0.8 2.1 GX 349+2 262.9011 -24.8311 7.6 45.7 -12.2 -0.1439 -1.5 7.8 GX 1+4 264.8858 -44.2766 4.1 27.9 -26.0 -0.1717 -2.8 12.1 4U 1735-44 270.1353 -24.9905 6.6 43.1 -3.6 -0.1564 -1.7 9.7 GX 5-1 270.3931 -25.6236 13.2 42.4 -3.6 -0.0755 -0.9 8.7 GRS 1758-258 273.8806 -13.9932 7.7 52.4 5.5 0.2810 1.5 7.7 GX 17+2 276.0659 -30.3460 7.8 36.2 1.2 -0.1066 -1.5 7.4 H1820-303 285.0963 -24.7853 18.3 39.4 16.3 0.0556 0.6 8.8 HT1900.1-2455 262.9986 -33.6872 4.1 37.7 -17.9 -0.2082 -2.8 8.9 GX 354-0 341.0981 -31.8111 2.4 39.6 98.1 1.0078 4.9 ------ UNKNOWN 17.8850 -76.0444 1.3 27.4 -170.2 0.4774 8.6 ------ UNKNOWN 215.8261 -55.8768 1.9 41.1 -81.3 1.2473 6.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: