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 23:37:04 EST 2014
Host Name: batevent1
Current Working Dir: /local/data/batevent/batevent_reproc/trigger318832
======================================================================
Trigger: 00318832 Segment: 000
BAT Trigger Time: 239382744.064 [s; MET]
Trigger Stop: 239382748.16 [s; MET]
UTC: 2008-08-02T15:12:21.075860 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 270.748505066349 Dec: -32.3332776459289 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.06
Image Trigger?: NO
Rate S/N Ratio: 8.30662386291807 [ if not an image trigger ]
Image S/N Ratio: 7.06
Analysis Position: [ source = BAT ]
RA: 270.748505066349 Dec: -32.3332776459289 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 270.722875126477 Dec: -32.3301747866931 [deg; J2000]
{ 18h 02m 53.5s , -32d 19' 48.6" }
+/- 1.52684706467876 [arcmin] (estimated 90% radius based on SNR)
+/- 0.7207415890143 [arcmin] (formal 1-sigma fit error)
SNR: 16.6170269792582
Angular difference between the analysis and refined position is 1.312655 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 179.503999978304 +/- 22.804894904492
Measured from: -16.9040000140667
to: 162.599999964237 [s; relative to TRIGTIME]
T50: 82.3839999735355 +/- 28.1373363257791
Measured from: -0.61599999666214
to: 81.7679999768734 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.70800000429153
to: 2.70800000429153 [s; relative to TRIGTIME]
Total Fluence
Measured from: -26.552000015974
to: 179.719999998808 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.778267 0.977388 0.551065 0.258595
0.086507 0.081624 0.072043 0.070701 [error]
Peak 0.017802 0.022657 0.023540 0.012348
0.006230 0.005848 0.005241 0.005075 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 206.272 -26.552 179.720
T90 179.504 -16.904 162.600
T50 82.384 -0.616 81.768
Peak 1.000 1.708 2.708
====== 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 -1.675 -0.181 0.178 - - - 7.03e-04 -7.84e-05 7.74e-05 53.290 57
CPL -0.977 -0.734 0.907 63.339 -16.744 -63.339 1.73e-03 -1.05e-03 3.87e-03 50.700 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 -1.205 -0.484 0.516 - - - 4.44e-03 -1.09e-03 1.09e-03 60.950 57
CPL -1.216 -0.472 0.534 9999.350 -9999.350 -9999.350 4.45e-03 -1.09e-03 1.44e-02 60.960 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 2.18e-07 3.60e-07 4.52e-07 1.13e-06 1.35e-06 2.16e-06 erg/cm2
90%_error_low -3.34e-08 -3.61e-08 -6.74e-08 -3.11e-07 -1.58e-07 -3.81e-07 erg/cm2
90%_error_hi 3.45e-08 3.61e-08 6.82e-08 3.87e-07 1.61e-07 4.42e-07 erg/cm2
Peak flux PL 1.38e-01 1.65e-01 1.43e-01 2.13e-01 5.21e-01 6.59e-01 ph/cm2/s
90%_error_low -6.48e-02 -5.07e-02 -4.34e-02 -1.13e-01 -1.32e-01 -1.70e-01 ph/cm2/s
90%_error_hi 7.58e-02 4.78e-02 4.20e-02 1.87e-01 1.32e-01 1.84e-01 ph/cm2/s
Fluence CPL 2.03e-07 3.90e-07 4.42e-07 3.55e-07 1.23e-06 1.39e-06 erg/cm2
90%_error_low -3.80e-08 -4.79e-08 -8.13e-08 -2.41e-07 -1.86e-07 -3.10e-07 erg/cm2
90%_error_hi 3.82e-08 4.99e-08 7.61e-08 8.17e-07 1.97e-07 8.53e-07 erg/cm2
Peak flux CPL 1.38e-01 1.65e-01 1.43e-01 2.11e-01 5.28e-01 6.63e-01 ph/cm2/s
90%_error_low N/A N/A N/A N/A N/A -2.26e-01 ph/cm2/s
90%_error_hi N/A N/A N/A N/A N/A 1.56e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 270.7229 -32.3302 0.0116 4.8637 173.5421 1.6623892 16.617 TRIG_00318832 Foreground time interval of the image: -26.552 41.437 (delta_t = 67.989 [sec]) Background time interval of the image: -239.064 -26.552 (delta_t = 212.512 [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 -26.552 sec. to 179.720 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.67467 ( -0.181227 0.177902 ) Norm@50keV : 7.02763E-04 ( -7.84184e-05 7.74007e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 53.29 using 59 PHA bins. # Reduced chi-squared = 0.9350 for 57 degrees of freedom # Null hypothesis probability = 6.149158e-01 Photon flux (15-150 keV) in 206.3 sec: 9.25279E-02 ( -0.0092831 0.0092891 ) ph/cm2/s Energy fluence (15-150 keV) : 1.34539e-06 ( -1.58015e-07 1.61141e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -26.552 sec. to 179.720 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.976517 ( -0.734489 0.906591 ) Epeak [keV] : 63.3388 ( -16.7436 -63.3388 ) Norm@50keV : 1.73367E-03 ( -0.00104595 0.00386776 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 50.70 using 59 PHA bins. # Reduced chi-squared = 0.9053 for 56 degrees of freedom # Null hypothesis probability = 6.751479e-01 Photon flux (15-150 keV) in 206.3 sec: 8.94573E-02 ( -0.0098187 0.0098238 ) ph/cm2/s Energy fluence (15-150 keV) : 1.23441e-06 ( -1.86317e-07 1.9659e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.708 sec. to 2.708 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.20474 ( -0.483638 0.51574 ) Norm@50keV : 4.43585E-03 ( -0.00108748 0.00108754 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 60.95 using 59 PHA bins. # Reduced chi-squared = 1.069 for 57 degrees of freedom # Null hypothesis probability = 3.357925e-01 Photon flux (15-150 keV) in 1 sec: 0.521030 ( -0.131543 0.132433 ) ph/cm2/s Energy fluence (15-150 keV) : 4.4949e-08 ( -1.24837e-08 1.28513e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.708 sec. to 2.708 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.21579 ( -0.473115 0.533195 ) Epeak [keV] : 9999.35 ( -9999.36 -9999.36 ) Norm@50keV : 4.45419E-03 ( -0.00109278 0.0143967 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 60.96 using 59 PHA bins. # Reduced chi-squared = 1.089 for 56 degrees of freedom # Null hypothesis probability = 3.021822e-01 Photon flux (15-150 keV) in 1 sec: 0.527798 ( ) ph/cm2/s Energy fluence (15-150 keV) : 4.53785e-08 ( -1.54393e-08 1.46476e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 179.504 sec. Hardness ratio (energy fluence ratio) = 1.25299684595
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 5.785092e-07 S(50-150 keV) = 7.669019e-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 = -8.455161124743028E-02, IMY = -9.570568996833929E-03
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: -239.064000 -26.552000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 244.9731 -15.6420 0.4 25.0 -49.4 6.6167 28.2 0.4 Sco X-1 256.1350 -37.8474 16.7 14.4 -120.9 0.1352 0.7 7.0 4U 1700-377 256.5846 -36.4187 3.4 13.2 -117.1 0.6741 3.4 7.2 GX 349+2 263.1259 -24.8734 6.4 5.7 -43.2 0.3624 1.8 10.0 GX 1+4 264.5781 -44.5712 7.7 17.0 -154.2 0.3023 1.5 10.1 4U 1735-44 268.3795 -1.4286 2.2 26.4 15.9 1.1544 5.3 1.6 SW J1753.5-0127 270.2948 -25.0071 2.2 3.3 45.9 1.0045 5.2 4.4 GX 5-1 270.4288 -25.6493 4.8 2.8 54.5 0.5026 2.5 8.9 GRS 1758-258 274.0042 -14.0585 3.3 14.7 37.7 0.7002 3.5 1.3 GX 17+2 275.8785 -30.3995 2.5 6.9 129.5 0.8769 4.7 3.1 H1820-303 285.2162 -25.0018 4.8 15.2 99.2 0.4917 2.4 11.0 HT1900.1-2455 288.7934 10.9009 4.1 43.5 45.9 1.8694 2.9 2.7 GRS 1915+105 262.9319 -33.8924 2.4 7.7 -126.8 0.9618 4.8 4.5 GX 354-0 333.1862 -55.0116 3.1 53.2 155.8 4.3603 3.7 ------ UNKNOWN 278.3592 13.9271 2.1 42.9 30.3 2.3278 5.6 ------ UNKNOWN 278.5370 -13.0355 2.1 17.5 50.5 1.0699 5.5 ------ UNKNOWN 325.7487 -73.1877 3.2 54.1 178.7 2.8485 3.6 ------ UNKNOWN 278.6495 -53.5424 2.3 26.7 -177.2 1.0434 5.0 ------ UNKNOWN 275.7964 -65.7524 2.0 38.2 -168.6 1.4430 5.8 ------ UNKNOWN 206.5144 -72.6773 4.8 55.3 -145.1 3.3360 2.4 ------ UNKNOWN 225.9556 1.9574 2.5 50.6 -44.8 4.8379 4.6 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -26.552000 41.436620 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 245.1044 -15.4743 24.7 25.0 -48.9 0.0594 0.5 12.3 Sco X-1 256.0550 -37.9841 4.7 14.5 -121.1 0.2802 2.5 9.0 4U 1700-377 256.5854 -36.2548 0.0 13.1 -116.6 -0.2377 -2.2 12.4 GX 349+2 263.1014 -24.8789 3.0 5.7 -43.4 -0.3836 -3.8 9.5 GX 1+4 264.6709 -44.5204 12.2 16.9 -154.4 -0.0952 -0.9 5.2 4U 1735-44 268.2848 -1.3206 5.9 26.5 15.7 -0.2330 -2.0 9.4 SW J1753.5-0127 270.2153 -24.9415 17.1 3.3 44.3 -0.0706 -0.7 9.1 GX 5-1 270.4794 -25.7513 20.4 2.7 56.5 0.0605 0.6 9.6 GRS 1758-258 273.9111 -14.2201 0.0 14.5 37.5 0.1579 1.5 12.3 GX 17+2 275.7051 -30.2796 737.0 6.7 129.0 0.0016 0.0 12.5 H1820-303 285.1515 -24.7851 5.1 15.2 98.4 0.2652 2.3 10.3 HT1900.1-2455 288.8396 10.9785 10.5 43.5 45.9 -0.4051 -1.1 3.1 GRS 1915+105 263.1762 -33.9114 8.5 7.6 -128.0 0.1368 1.4 10.4 GX 354-0 270.7229 -32.3301 0.7 4.9 173.5 1.6623 16.6 ------ UNKNOWN 279.8439 -53.0811 2.2 26.6 -179.1 0.5914 5.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 67.036600 404.336600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 244.9764 -15.6408 0.5 28.7 -49.7 9.2757 24.7 0.2 Sco X-1 256.1260 -37.7435 3.4 13.1 -107.5 0.9525 3.4 9.0 4U 1700-377 256.4093 -36.3859 13.1 12.5 -102.0 0.2461 0.9 2.6 GX 349+2 263.1090 -24.8840 6.5 10.0 -33.0 0.4637 1.8 9.9 GX 1+4 264.9622 -44.5755 95.6 13.1 -150.5 -0.0350 -0.1 12.0 4U 1735-44 268.3428 -1.4878 1.6 30.9 6.3 2.2694 7.0 2.6 SW J1753.5-0127 270.2905 -25.0505 1.7 7.3 7.7 1.7417 7.0 1.8 GX 5-1 270.3108 -25.6880 4.0 6.6 7.5 0.7760 3.1 3.3 GRS 1758-258 274.0193 -13.9909 3.4 18.6 21.0 0.9039 3.4 2.8 GX 17+2 275.8567 -30.3120 3.0 4.8 77.6 1.0181 3.8 4.8 H1820-303 285.0520 -25.0538 4.3 14.5 74.5 0.7171 2.7 8.0 HT1900.1-2455 288.7976 10.9824 3.0 46.6 35.7 3.4171 3.9 2.2 GRS 1915+105 263.0938 -33.7964 3.3 6.6 -94.1 0.9851 3.5 5.7 GX 354-0 322.4896 -36.6978 2.6 42.4 121.8 4.8780 4.4 ------ UNKNOWN 311.5024 -46.1973 3.1 34.0 137.0 1.7563 3.8 ------ UNKNOWN 236.0012 11.9969 3.2 55.4 -31.7 5.6540 3.6 ------ UNKNOWN 229.3365 -5.4242 3.7 47.0 -53.2 4.3568 3.2 ------ UNKNOWN