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 01:01:27 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger315080
======================================================================
Trigger: 00315080 Segment: 000
BAT Trigger Time: 235909531.328 [s; MET]
Trigger Stop: 235909531.84 [s; MET]
UTC: 2008-06-23T10:25:28.440240 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 237.659837169095 Dec: -62.0380947683357 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.53
Image Trigger?: NO
Rate S/N Ratio: 12.0415945787923 [ if not an image trigger ]
Image S/N Ratio: 7.53
Analysis Position: [ source = BAT ]
RA: 237.659837169095 Dec: -62.0380947683357 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 237.668441406388 Dec: -62.0455425189205 [deg; J2000]
{ 15h 50m 40.4s , -62d 02' 44.0" }
+/- 1.38246549980321 [arcmin] (estimated 90% radius based on SNR)
+/- 0.654216412067809 [arcmin] (formal 1-sigma fit error)
SNR: 19.1506563344011
Angular difference between the analysis and refined position is 0.508202 arcmin
Partial Coding Fraction: 0.3320312 [ including projection effects ]
Duration
T90: 15.0959999859333 +/- 5.118077772016
Measured from: -0.159999996423721
to: 14.9359999895096 [s; relative to TRIGTIME]
T50: 6.26800003647804 +/- 0.972306533017859
Measured from: 1.35599997639656
to: 7.6240000128746 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 7.22799998521805
to: 8.22799998521805 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.672000020742416
to: 15.972000002861 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.380995 0.540481 0.502730 0.148680
0.039855 0.041942 0.038905 0.038140 [error]
Peak 0.049724 0.096819 0.075989 0.024772
0.010300 0.011602 0.010847 0.009322 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 16.644 -0.672 15.972
T90 15.096 -0.160 14.936
T50 6.268 1.356 7.624
Peak 1.000 7.228 8.228
====== 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 -1.271 -0.150 0.150 - - - 6.39e-03 -5.10e-04 5.10e-04 66.800 57
CPL -1.267 -0.151 0.152 9998.760 -9998.760 -9998.760 6.41e-03 -6.41e-03 4.38e-03 66.800 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 -1.286 -0.230 0.230 - - - 1.60e-02 -2.28e-03 2.27e-03 49.680 57
CPL -0.095 -1.079 1.495 80.221 -21.620 237.392 6.37e-02 -6.37e-02 2.86e-01 46.060 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 1.10e-07 2.32e-07 3.84e-07 1.44e-06 1.06e-06 2.17e-06 erg/cm2
90%_error_low -1.68e-08 -2.12e-08 -3.85e-08 -3.05e-07 -9.48e-08 -3.32e-07 erg/cm2
90%_error_hi 1.77e-08 2.10e-08 3.81e-08 3.60e-07 9.56e-08 3.78e-07 erg/cm2
Peak flux PL 5.38e-01 6.15e-01 5.04e-01 6.93e-01 1.91e+00 2.35e+00 ph/cm2/s
90%_error_low -1.27e-01 -9.54e-02 -8.58e-02 -2.12e-01 -2.71e-01 -3.46e-01 ph/cm2/s
90%_error_hi 1.35e-01 9.43e-02 8.49e-02 2.62e-01 2.72e-01 3.54e-01 ph/cm2/s
Fluence CPL 1.11e-07 2.31e-07 3.82e-07 1.47e-06 1.06e-06 2.16e-06 erg/cm2
90%_error_low -2.60e-08 -2.13e-08 -4.34e-08 -8.21e-07 -1.18e-07 -7.17e-07 erg/cm2
90%_error_hi 2.04e-08 2.31e-08 5.13e-08 3.83e-07 8.14e-08 1.89e-07 erg/cm2
Peak flux CPL 4.34e-01 6.85e-01 5.51e-01 2.26e-01 1.83e+00 1.90e+00 ph/cm2/s
90%_error_low -1.54e-01 -1.18e-01 -1.02e-01 N/A -2.85e-01 -3.28e-01 ph/cm2/s
90%_error_hi 1.63e-01 1.25e-01 1.04e-01 N/A 2.83e-01 4.39e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 237.6684 -62.0455 0.0100 31.2902 107.4480 1.6282712 19.151 TRIG_00315080 Foreground time interval of the image: -0.672 15.972 (delta_t = 16.644 [sec]) Background time interval of the image: -299.227 -0.672 (delta_t = 298.555 [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 -0.672 sec. to 15.972 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.27144 ( -0.149756 0.150421 ) Norm@50keV : 6.38708E-03 ( -0.000510119 0.00050991 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 66.80 using 59 PHA bins. # Reduced chi-squared = 1.172 for 57 degrees of freedom # Null hypothesis probability = 1.758210e-01 Photon flux (15-150 keV) in 16.64 sec: 0.758138 ( -0.062639 0.062832 ) ph/cm2/s Energy fluence (15-150 keV) : 1.05787e-06 ( -9.48131e-08 9.56422e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.672 sec. to 15.972 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.2673 ( -0.150836 0.152385 ) Epeak [keV] : 9998.76 ( -9998.99 -9998.99 ) Norm@50keV : 6.41484E-03 ( -0.00641482 0.00438226 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 66.80 using 59 PHA bins. # Reduced chi-squared = 1.193 for 56 degrees of freedom # Null hypothesis probability = 1.529744e-01 Photon flux (15-150 keV) in 16.64 sec: 0.757974 ( ) ph/cm2/s Energy fluence (15-150 keV) : 1.06285e-06 ( -1.17959e-07 8.14293e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 7.228 sec. to 8.228 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.28604 ( -0.230203 0.2303 ) Norm@50keV : 1.60441E-02 ( -0.00227505 0.0022705 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 49.68 using 59 PHA bins. # Reduced chi-squared = 0.8716 for 57 degrees of freedom # Null hypothesis probability = 7.435466e-01 Photon flux (15-150 keV) in 1 sec: 1.90929 ( -0.27144 0.27178 ) ph/cm2/s Energy fluence (15-150 keV) : 1.59107e-07 ( -2.51424e-08 2.54668e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.228 sec. to 8.228 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.0950373 ( -1.07853 1.49459 ) Epeak [keV] : 80.2209 ( -21.6201 237.392 ) Norm@50keV : 6.36741E-02 ( -0.0636741 0.285773 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 46.06 using 59 PHA bins. # Reduced chi-squared = 0.8226 for 56 degrees of freedom # Null hypothesis probability = 8.256105e-01 Photon flux (15-150 keV) in 1 sec: 1.82998 ( -0.28475 0.28286 ) ph/cm2/s Energy fluence (15-150 keV) : 5.51417e-08 ( -4.8258e-08 8.29491e-09 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 15.096 sec. Hardness ratio (energy fluence ratio) = 1.65702875489
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 3.412625e-07 S(50-150 keV) = 7.166181e-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 = -1.822349757174955E-01, IMY = -5.798109609086134E-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: -299.227410 -0.672000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5503 -40.5555 1.1 28.9 -80.1 3.4765 10.6 1.0 Vela X-1 170.3005 -60.6568 0.9 0.8 165.8 2.9838 12.8 2.1 Cen X-3 186.8885 -62.6248 3.1 8.4 100.3 0.8204 3.7 10.8 GX 301-2 301.8303 -72.6110 3.5 43.5 144.8 2.0913 3.3 ------ UNKNOWN 186.6590 -54.3434 2.9 10.4 49.1 0.9035 3.9 ------ UNKNOWN 52.7719 -73.2096 2.9 40.5 -173.0 1.4213 4.1 ------ UNKNOWN 27.4030 -61.2813 3.2 55.6 -175.6 3.5129 3.6 ------ UNKNOWN 128.7580 -48.6088 5.4 26.2 -99.6 0.7236 2.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.672000 15.972000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.7080 -40.6297 4.7 28.8 -79.9 -0.1589 -2.5 9.3 Vela X-1 170.3009 -60.4647 14.8 0.6 166.3 0.0349 0.8 9.5 Cen X-3 186.3328 -62.7229 5.5 8.2 101.4 0.0982 2.1 9.3 GX 301-2 237.6684 -62.0455 0.6 31.3 107.4 1.6283 19.2 ------ UNKNOWN 78.3178 -75.1230 2.4 33.8 -168.7 0.2657 4.8 ------ UNKNOWN 135.2435 -24.5822 1.9 42.8 -66.5 1.0832 6.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 1307.272590 1389.742600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 170.2844 -60.6769 3.9 30.8 -75.7 0.4616 3.0 3.4 Cen X-3 187.0053 -62.6356 0.0 22.9 -71.6 0.0449 0.4 12.5 GX 301-2 255.8687 -37.7418 7.1 26.8 75.9 0.2227 1.6 8.3 4U 1700-377 256.2658 -36.4673 5.0 28.1 75.6 0.3327 2.3 8.6 GX 349+2 264.5682 -44.3920 10.5 23.6 96.6 0.1332 1.1 8.3 4U 1735-44 275.8636 -30.3524 4.3 40.2 98.4 1.0996 2.7 3.3 H1820-303 262.7919 -33.8681 7.7 32.4 83.8 0.2915 1.5 10.0 GX 354-0 283.8861 -57.0048 2.5 23.5 141.3 0.4832 4.6 ------ UNKNOWN 1.8708 -52.7524 3.1 57.1 -174.1 1.6574 3.7 ------ UNKNOWN 4.7983 -52.1929 2.7 58.4 -172.5 2.3989 4.3 ------ UNKNOWN