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 23:46:16 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger318101
======================================================================
Trigger: 00318101 Segment: 000
BAT Trigger Time: 238839207.932 [s; MET]
Trigger Stop: 238839207.996 [s; MET]
UTC: 2008-07-27T08:13:24.959660 [includes UTCF correction]
Where From?: (*SHORT BURST*) TDRSS scaled map message
BAT
RA: 276.869989337883 Dec: 1.17214157120085 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.73
Image Trigger?: NO
Rate S/N Ratio: 38.2230297072328 [ if not an image trigger ]
Image S/N Ratio: 10.73
Analysis Position: [ source = BAT ]
RA: 276.869989337883 Dec: 1.17214157120085 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 276.870989833797 Dec: 1.17146338741443 [deg; J2000]
{ 18h 27m 29.0s , +01d 10' 17.3" }
+/- 0.561629285745347 [arcmin] (estimated 90% radius based on SNR)
+/- 0.158594091910801 [arcmin] (formal 1-sigma fit error)
SNR: 69.3501356236702
Angular difference between the analysis and refined position is 0.072511 arcmin
Partial Coding Fraction: 0.6875 [ including projection effects ]
Duration
T90: 8.66400000452995 +/- 0.145602189925778
Measured from: 0.0919999778270721
to: 8.75599998235703 [s; relative to TRIGTIME]
T50: 6.31600001454353 +/- 0.110634524953673
Measured from: 1.01199999451637
to: 7.32800000905991 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: -0.0400000214576721
to: 0.959999978542328 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.236000001430511
to: 9.50399997830391 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.770853 1.453200 1.562249 0.501614
0.026802 0.028545 0.027684 0.021116 [error]
Peak 0.162509 0.300906 0.376484 0.130754
0.009796 0.011470 0.011779 0.008953 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 9.740 -0.236 9.504
T90 8.664 0.092 8.756
T50 6.316 1.012 7.328
Peak 1.000 -0.040 0.960
====== 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 -1.045 -0.042 0.042 - - - 3.09e-02 -7.17e-04 7.16e-04 44.490 57
CPL -0.864 -0.163 0.170 385.724 -155.063 2218.556 3.67e-02 -2.85e-03 6.19e-03 40.910 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 -0.898 -0.068 0.068 - - - 6.63e-02 -2.55e-03 2.54e-03 47.780 57
CPL -0.731 -0.193 0.271 459.657 -459.657 -459.657 7.80e-02 -9.95e-03 2.27e-02 46.550 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 2.51e-07 6.11e-07 1.18e-06 5.64e-06 3.20e-06 7.69e-06 erg/cm2
90%_error_low -1.26e-08 -1.81e-08 -2.85e-08 -3.20e-07 -7.47e-08 -3.30e-07 erg/cm2
90%_error_hi 1.29e-08 1.81e-08 2.84e-08 3.33e-07 7.48e-08 3.41e-07 erg/cm2
Peak flux PL 1.54e+00 2.22e+00 2.38e+00 4.76e+00 7.61e+00 1.09e+01 ph/cm2/s
90%_error_low -1.25e-01 -1.11e-01 -9.43e-02 -4.09e-01 -2.93e-01 -4.60e-01 ph/cm2/s
90%_error_hi 1.30e-01 1.10e-01 9.40e-02 4.34e-01 2.93e-01 4.67e-01 ph/cm2/s
Fluence CPL 2.38e-07 6.14e-07 1.21e-06 4.55e-06 3.18e-06 6.61e-06 erg/cm2
90%_error_low -1.70e-08 -1.87e-08 -3.57e-08 -7.87e-07 -7.78e-08 -7.81e-07 erg/cm2
90%_error_hi 1.74e-08 1.87e-08 3.59e-08 9.81e-07 7.76e-08 9.70e-07 erg/cm2
Peak flux CPL 1.46e+00 2.23e+00 2.43e+00 4.03e+00 7.56e+00 1.02e+01 ph/cm2/s
90%_error_low -1.65e-01 -1.14e-01 -1.19e-01 -8.89e-01 -3.04e-01 -9.45e-01 ph/cm2/s
90%_error_hi 6.90e-02 1.14e-01 1.21e-01 8.46e-01 3.04e-01 9.48e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 276.8710 1.1715 0.0028 27.2378 28.7244 4.2499306 69.350 TRIG_00318101 Foreground time interval of the image: -0.236 8.969 (delta_t = 9.205 [sec]) Background time interval of the image: -375.831 -272.868 (delta_t = 102.963 [sec]) -239.932 -0.236 (delta_t = 239.696 [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 -0.236 sec. to 9.504 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.04542 ( -0.0416801 0.0419122 ) Norm@50keV : 3.08787E-02 ( -0.000717056 0.000715643 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 44.49 using 59 PHA bins. # Reduced chi-squared = 0.7805 for 57 degrees of freedom # Null hypothesis probability = 8.862805e-01 Photon flux (15-150 keV) in 9.74 sec: 3.56518 ( -0.08643 0.08659 ) ph/cm2/s Energy fluence (15-150 keV) : 3.20176e-06 ( -7.46822e-08 7.48043e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.236 sec. to 9.504 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.86416 ( -0.163215 0.169948 ) Epeak [keV] : 385.724 ( -155.063 2218.55 ) Norm@50keV : 3.66510E-02 ( -0.00284783 0.00618693 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 40.91 using 59 PHA bins. # Reduced chi-squared = 0.7305 for 56 degrees of freedom # Null hypothesis probability = 9.350410e-01 Photon flux (15-150 keV) in 9.74 sec: 3.52713 ( -0.09229 0.09257 ) ph/cm2/s Energy fluence (15-150 keV) : 3.18016e-06 ( -7.77503e-08 7.76003e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.040 sec. to 0.960 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.897788 ( -0.0675828 0.0683234 ) Norm@50keV : 6.62900E-02 ( -0.0025527 0.00254154 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 47.78 using 59 PHA bins. # Reduced chi-squared = 0.8382 for 57 degrees of freedom # Null hypothesis probability = 8.028314e-01 Photon flux (15-150 keV) in 1 sec: 7.60841 ( -0.29297 0.29326 ) ph/cm2/s Energy fluence (15-150 keV) : 7.44663e-07 ( -3.01338e-08 3.02091e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.040 sec. to 0.960 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.731229 ( -0.192988 0.270918 ) Epeak [keV] : 459.657 ( -459.657 -459.657 ) Norm@50keV : 7.79789E-02 ( -0.0099473 0.0226561 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 46.55 using 59 PHA bins. # Reduced chi-squared = 0.8313 for 56 degrees of freedom # Null hypothesis probability = 8.118458e-01 Photon flux (15-150 keV) in 1 sec: 7.55503 ( -0.30371 0.30387 ) ph/cm2/s Energy fluence (15-150 keV) : 7.40014e-07 ( -3.1269e-08 3.11558e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 8.664 sec. Hardness ratio (energy fluence ratio) = 1.93802696074
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 8.621235e-07 S(50-150 keV) = 2.33967e-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 = 4.514183272895041E-01, IMY = -2.473942593577021E-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: -375.831400 -272.868400 -239.932000 -0.236000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 244.9817 -15.6326 0.3 29.1 -52.2 12.5978 36.8 0.5 Sco X-1 255.9078 -37.8101 1.8 19.5 -109.1 1.7379 6.2 4.3 4U 1700-377 256.2565 -36.3331 4.1 18.5 -105.6 0.7974 2.8 10.2 GX 349+2 263.2150 -24.8393 0.0 10.0 -63.2 0.4156 1.6 12.6 GX 1+4 264.8726 -44.3492 10.4 19.9 -137.2 0.2734 1.1 8.2 4U 1735-44 268.3485 -1.4151 2.5 25.2 9.0 1.3313 4.7 2.5 SW J1753.5-0127 270.2906 -25.0798 3.0 3.6 -54.2 1.0686 3.9 0.4 GX 5-1 270.2637 -25.7788 3.2 3.5 -65.3 1.0047 3.6 3.0 GRS 1758-258 274.0218 -14.0373 0.8 11.9 22.0 3.2667 13.8 0.9 GX 17+2 275.7437 -30.3544 4.6 4.6 -173.9 0.6874 2.5 9.4 H1820-303 284.9453 -24.7966 7.4 9.8 108.5 0.3811 1.6 8.9 HT1900.1-2455 288.8381 10.9296 1.7 39.5 45.8 4.6010 6.9 2.5 GRS 1915+105 263.2091 -33.9146 3.7 12.4 -109.7 0.8440 3.1 12.0 GX 354-0 287.4268 6.2411 3.3 34.7 46.5 1.5764 3.5 ------ UNKNOWN 339.5633 -68.1915 3.6 56.9 179.1 5.9014 3.2 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.236000 8.968600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 245.0970 -15.7518 16.8 29.0 -52.3 -0.0467 -0.7 9.5 Sco X-1 255.7922 -37.8454 3.3 19.6 -109.0 -0.2072 -3.5 9.2 4U 1700-377 256.5877 -36.2998 3.4 18.2 -106.0 0.1999 3.4 10.4 GX 349+2 262.9117 -24.6189 8.2 10.3 -62.2 0.0773 1.4 9.3 GX 1+4 264.7396 -44.4499 15.3 20.0 -137.1 0.0421 0.8 0.1 4U 1735-44 268.3905 -1.6040 5.4 25.0 9.0 0.1249 2.1 9.2 SW J1753.5-0127 270.4289 -25.0026 43.4 3.5 -52.5 0.0130 0.3 9.1 GX 5-1 270.3837 -25.7025 9.0 3.4 -63.9 -0.0658 -1.3 5.0 GRS 1758-258 273.8670 -14.0959 6.0 11.9 21.3 0.0999 1.9 8.8 GX 17+2 275.9494 -30.3773 61.0 4.7 -175.9 -0.0101 -0.2 1.4 H1820-303 285.1855 -24.8568 13.5 10.0 109.0 0.0463 0.9 9.0 HT1900.1-2455 288.8203 11.0116 5.1 39.6 45.8 0.3168 2.3 4.2 GRS 1915+105 263.1108 -33.6967 4.8 12.3 -108.7 0.1276 2.4 10.3 GX 354-0 276.8710 1.1715 0.2 27.2 28.7 4.2498 69.3 ------ UNKNOWN 332.6135 -79.3812 3.1 58.9 -167.7 1.1466 3.8 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 83.168590 656.268590 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 245.0008 -15.6568 0.4 35.7 -155.1 16.1821 27.6 1.6 Sco X-1 254.3037 35.2615 11.7 40.0 -64.9 1.8317 1.0 9.0 Her X-1 256.0232 -37.9153 3.7 43.6 168.4 2.6430 3.1 4.6 4U 1700-377 256.5114 -36.4705 6.3 42.1 169.0 1.5167 1.8 4.6 GX 349+2 262.9108 -24.8657 6.3 29.4 170.9 0.9626 1.8 9.0 GX 1+4 264.7693 -44.4298 4.7 46.9 156.2 3.2977 2.5 1.7 4U 1735-44 268.3778 -1.4619 1.8 8.9 -142.9 2.9484 6.3 0.8 SW J1753.5-0127 270.3036 -25.2715 0.0 27.2 157.4 1.0511 1.8 11.6 GX 5-1 270.3390 -25.7314 7.9 27.6 157.1 0.9218 1.6 2.1 GRS 1758-258 273.9812 -14.0468 1.4 15.5 154.9 3.5482 8.3 1.6 GX 17+2 275.9199 -30.3509 5.3 31.5 145.9 1.5309 2.2 1.0 H1820-303 285.1414 -25.0327 6.6 27.4 127.9 -1.0563 -1.7 8.8 HT1900.1-2455 288.8150 10.9733 0.6 15.4 14.2 8.2066 20.4 1.9 GRS 1915+105 299.5662 35.2178 0.4 40.1 -6.4 18.8654 29.6 1.5 Cyg X-1 308.1956 40.9099 5.8 48.8 -4.2 2.1177 2.0 4.6 Cyg X-3 263.1194 -33.8138 4.8 37.3 163.3 1.7907 2.4 6.6 GX 354-0 313.9614 -12.7530 3.1 39.3 76.2 6.7306 3.7 ------ UNKNOWN 314.1883 -12.3117 3.7 39.4 75.5 5.9947 3.4 ------ UNKNOWN 267.3173 -48.6008 3.4 50.5 152.5 6.6141 3.4 ------ UNKNOWN 302.7436 -7.4416 2.2 27.2 73.2 3.2979 5.2 ------ UNKNOWN 252.2535 -34.2455 2.4 42.3 175.1 3.6357 4.9 ------ UNKNOWN UNKNOWN UNKNOWN UNKNOWN