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 20 08:27:46 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger285653
======================================================================
Trigger: 00285653 Segment: 000
BAT Trigger Time: 206704858.432 [s; MET]
Trigger Stop: 206704859.456 [s; MET]
UTC: 2007-07-21T10:00:56.330340 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 3.17553944498637 Dec: -28.5479948098393 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.23
Image Trigger?: NO
Rate S/N Ratio: 10.0498756211209 [ if not an image trigger ]
Image S/N Ratio: 8.23
Analysis Position: [ source = BAT ]
RA: 3.17553944498637 Dec: -28.5479948098393 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 3.14623321544184 Dec: -28.5321642938372 [deg; J2000]
{ 00h 12m 35.1s , -28d 31' 55.8" }
+/- 2.29562272531626 [arcmin] (estimated 90% radius based on SNR)
+/- 0.915908879229685 [arcmin] (formal 1-sigma fit error)
SNR: 9.27996237046778
Angular difference between the analysis and refined position is 1.813362 arcmin
Partial Coding Fraction: 0.7265625 [ including projection effects ]
Duration
T90: 3.34800001978874 +/- 0.454844996324233
Measured from: -0.00400000810623169
to: 3.34400001168251 [s; relative to TRIGTIME]
T50: 1.78000000119209 +/- 0.859325303772148
Measured from: 0.5
to: 2.28000000119209 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.119999974966049
to: 1.11999997496605 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.120000004768372
to: 3.44799998402596 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.075288 0.062552 0.014891 0.017087
0.010335 0.010786 0.009071 0.007809 [error]
Peak 0.035156 0.032200 0.007338 0.001794
0.005767 0.005823 0.004798 0.004219 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 3.568 -0.120 3.448
T90 3.348 -0.004 3.344
T50 1.780 0.500 2.280
Peak 1.000 0.120 1.120
====== 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 -2.348 -0.388 0.343 - - - 2.12e-03 -6.20e-04 6.22e-04 67.370 57
CPL 1.346 -2.547 7.602 26.907 -5.303 5.611 8.17e-01 -8.17e-01 2.85e+05 60.740 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 -2.337 -0.436 0.380 - - - 3.77e-03 -1.20e-03 1.19e-03 48.240 57
CPL 0.257 -2.119 6.213 27.024 -3.327 8.220 2.26e-01 -2.26e-01 6.05e+03 45.050 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 2.16e-08 2.38e-08 1.87e-08 2.42e-08 7.30e-08 8.82e-08 erg/cm2
90%_error_low -4.83e-09 -5.12e-09 -6.85e-09 -1.33e-08 -1.72e-08 -2.52e-08 erg/cm2
90%_error_hi 4.87e-09 5.03e-09 7.70e-09 2.18e-08 1.82e-08 3.16e-08 erg/cm2
Peak flux PL 3.49e-01 2.15e-01 8.51e-02 4.53e-02 6.72e-01 6.94e-01 ph/cm2/s
90%_error_low -8.81e-02 -4.90e-02 -3.32e-02 -2.58e-02 -1.41e-01 -1.47e-01 ph/cm2/s
90%_error_hi 8.99e-02 4.80e-02 3.68e-02 4.19e-02 1.41e-01 1.48e-01 ph/cm2/s
Fluence CPL N/A N/A N/A N/A N/A N/A erg/cm2
90%_error_low -4.83e-09 -5.12e-09 -6.85e-09 -1.33e-08 -1.72e-08 -2.52e-08 erg/cm2
90%_error_hi 4.87e-09 5.03e-09 7.70e-09 2.18e-08 1.82e-08 3.16e-08 erg/cm2
Peak flux CPL 3.49e-01 2.17e-01 8.17e-02 5.00e-02 6.77e-01 6.87e-01 ph/cm2/s
90%_error_low -1.75e-01 -5.18e-02 -3.76e-02 -2.08e-02 -1.45e-01 -1.36e-01 ph/cm2/s
90%_error_hi 9.12e-02 4.65e-02 5.24e-02 4.69e-02 1.37e-01 1.57e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name
3.1462 -28.5322 0.0208 31.8690 5.6326 0.1886715 9.280 TRIG_00285653
Foreground time interval of the image:
-0.120 3.448 (delta_t = 3.568 [sec])
Background time interval of the image:
-77.131 -0.120 (delta_t = 77.011 [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 -0.120 sec. to 3.448 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.34835 ( -0.387979 0.343402 ) Norm@50keV : 2.12041E-03 ( -0.000619322 0.000622627 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 67.37 using 59 PHA bins. # Reduced chi-squared = 1.182 for 57 degrees of freedom # Null hypothesis probability = 1.636999e-01 Photon flux (15-150 keV) in 3.568 sec: 0.380832 ( -0.073091 0.073154 ) ph/cm2/s Energy fluence (15-150 keV) : 7.29884e-08 ( -1.71948e-08 1.82179e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.120 sec. to 3.448 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: 2.40451 ( -2.57731 7.5717 ) Epeak [keV] : 26.7815 ( -5.30256 5.61205 ) Norm@50keV : 4.88282 ( -4.72484 285353 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 60.62 using 59 PHA bins. # Reduced chi-squared = 1.082 for 56 degrees of freedom # Null hypothesis probability = 3.129813e-01 Photon flux (15-150 keV) in 3.568 sec: 0.363890 ( -0.070165 0.070658 ) 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 0.120 sec. to 1.120 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.33685 ( -0.435859 0.380055 ) Norm@50keV : 3.76729E-03 ( -0.00120098 0.00119477 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 48.24 using 59 PHA bins. # Reduced chi-squared = 0.8464 for 57 degrees of freedom # Null hypothesis probability = 7.890116e-01 Photon flux (15-150 keV) in 1 sec: 0.672213 ( -0.140891 0.140951 ) ph/cm2/s Energy fluence (15-150 keV) : 3.62635e-08 ( -9.28797e-09 9.84277e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.120 sec. to 1.120 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: 1.12012 ( -2.15361 6.17834 ) Epeak [keV] : 27.3450 ( -3.37307 8.17439 ) Norm@50keV : 0.926486 ( -0.873941 6048.77 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 44.97 using 59 PHA bins. # Reduced chi-squared = 0.8030 for 56 degrees of freedom # Null hypothesis probability = 8.545075e-01 Photon flux (15-150 keV) in 1 sec: 0.676881 ( -0.145418 0.137014 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 3.348 sec. Hardness ratio (energy fluence ratio) = 0.785380499476
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 4.533392e-08 S(50-150 keV) = 2.7656825e-08
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 = 6.186923740375682E-01, IMY = -6.101821912772279E-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: -77.131410 -0.120000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 326.2622 38.3558 2.9 44.3 169.3 0.5997 4.0 4.7 Cyg X-2 342.7989 -48.2214 2.4 51.3 30.5 1.8114 4.8 ------ UNKNOWN 316.3383 30.6859 2.1 45.7 153.5 1.1119 5.5 ------ UNKNOWN 316.1696 40.3081 2.5 51.3 164.0 1.3141 4.7 ------ UNKNOWN 351.4484 36.5794 2.3 34.5 -162.8 0.4493 4.9 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.120000 3.448000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 326.2004 38.5169 0.0 44.4 169.4 -0.0491 -1.5 11.8 Cyg X-2 3.1462 -28.5322 1.2 31.9 5.6 0.1887 9.3 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 67.468600 962.627600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 329.1010 -37.5507 2.9 29.7 70.6 2.2003 3.9 ------ UNKNOWN 344.7935 -35.7815 2.3 17.1 67.4 1.8174 5.0 ------ UNKNOWN 64.9053 -46.4855 4.8 50.7 -44.5 5.7207 2.4 ------ UNKNOWN 59.4791 -40.2264 4.9 47.1 -53.1 5.1197 2.4 ------ UNKNOWN