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 Aug 6 18:19:31 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger848932
======================================================================
Trigger: 00848932 Segment: 000
BAT Trigger Time: 553818258.944 [s; MET]
Trigger Stop: 553818259.968 [s; MET]
UTC: 2018-07-20T22:23:57.647680 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 265.623311909688 Dec: -26.5838055962637 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 9.38
Image Trigger?: NO
Rate S/N Ratio: 18.6010752377383 [ if not an image trigger ]
Image S/N Ratio: 9.38
Analysis Position: [ source = BAT ]
RA: 265.623311909688 Dec: -26.5838055962637 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 265.65478018523 Dec: -26.6330597934651 [deg; J2000]
{ 17h 42m 37.1s , -26d 37' 59.0" }
+/- 1.63943636821766 [arcmin] (estimated 90% radius based on SNR)
+/- 0.574202004641546 [arcmin] (formal 1-sigma fit error)
SNR: 15.0110772040885
Angular difference between the analysis and refined position is 3.403422 arcmin
Partial Coding Fraction: 0.984375 [ including projection effects ]
Duration
T90: 122.987999916077 +/- 31.6700540667226
Measured from: -112.22000002861
to: 10.7679998874664 [s; relative to TRIGTIME]
T50: 40.8039999008179 +/- 29.5499460902793
Measured from: -37.2039999961853
to: 3.59999990463257 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 3.22000002861023
to: 4.22000002861023 [s; relative to TRIGTIME]
Total Fluence
Measured from: -150.519999980927
to: 13.444000005722 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.943616 1.286482 1.051983 0.302394
0.090618 0.083619 0.071488 0.062669 [error]
Peak 0.035440 0.050664 0.048450 0.017851
0.007452 0.007331 0.006379 0.005432 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 163.964 -150.520 13.444
T90 122.988 -112.220 10.768
T50 40.804 -37.204 3.600
Peak 1.000 3.220 4.220
====== 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 -1.388 -0.131 0.131 - - - 1.44e-03 -9.90e-05 9.89e-05 53.030 57
CPL -1.385 -0.131 0.230 9999.290 -9999.290 -9999.290 1.44e-03 -9.93e-05 4.68e-04 53.060 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 -1.239 -0.243 0.248 - - - 1.00e-02 -1.38e-03 1.38e-03 62.790 57
CPL -0.831 -0.532 1.148 156.459 -156.459 -156.459 1.55e-02 -6.68e-03 3.47e-02 62.250 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 2.71e-07 5.33e-07 8.15e-07 2.72e-06 2.28e-06 4.33e-06 erg/cm2
90%_error_low -3.58e-08 -4.16e-08 -7.13e-08 -5.06e-07 -1.73e-07 -5.54e-07 erg/cm2
90%_error_hi 3.74e-08 4.12e-08 7.09e-08 5.87e-07 1.74e-07 6.21e-07 erg/cm2
Peak flux PL 3.22e-01 3.78e-01 3.21e-01 4.60e-01 1.18e+00 1.48e+00 ph/cm2/s
90%_error_low -8.34e-02 -6.26e-02 -5.12e-02 -1.40e-01 -1.70e-01 -2.10e-01 ph/cm2/s
90%_error_hi 9.12e-02 6.15e-02 5.05e-02 1.75e-01 1.70e-01 2.14e-01 ph/cm2/s
Fluence CPL 2.75e-07 5.29e-07 8.09e-07 2.90e-06 2.30e-06 4.18e-06 erg/cm2
90%_error_low N/A -5.27e-08 -9.07e-08 -1.12e-06 -1.88e-07 -7.93e-07 erg/cm2
90%_error_hi N/A 5.99e-08 1.01e-07 6.96e-08 1.60e-07 7.35e-07 erg/cm2
Peak flux CPL 2.92e-01 3.88e-01 3.34e-01 3.03e-01 1.16e+00 1.32e+00 ph/cm2/s
90%_error_low -1.05e-01 -6.70e-02 -5.93e-02 -1.80e-01 -1.79e-01 -2.72e-01 ph/cm2/s
90%_error_hi 1.11e-01 6.93e-02 6.17e-02 2.07e-01 1.79e-01 2.85e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 265.6548 -26.6331 0.0128 19.1842 -2.0787 3.9701766 15.011 TRIG_00848932 Foreground time interval of the image: -150.520 13.444 (delta_t = 163.964 [sec]) Background time interval of the image: -239.944 -150.520 (delta_t = 89.424 [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 -150.520 sec. to 13.444 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.38805 ( -0.130523 0.131492 ) Norm@50keV : 1.43644E-03 ( -9.89996e-05 9.89009e-05 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 53.03 using 59 PHA bins. # Reduced chi-squared = 0.9304 for 57 degrees of freedom # Null hypothesis probability = 6.246793e-01 Photon flux (15-150 keV) in 164 sec: 0.174467 ( -0.012614 0.012683 ) ph/cm2/s Energy fluence (15-150 keV) : 2.28221e-06 ( -1.73027e-07 1.74219e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -150.520 sec. to 13.444 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.38485 ( -0.131319 0.230498 ) Epeak [keV] : 9999.29 ( -9999.36 -9999.36 ) Norm@50keV : 1.44160E-03 ( -9.93206e-05 0.000468238 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 53.06 using 59 PHA bins. # Reduced chi-squared = 0.9474 for 56 degrees of freedom # Null hypothesis probability = 5.870245e-01 Photon flux (15-150 keV) in 164 sec: 0.175594 ( -0.021736 0.016241 ) ph/cm2/s Energy fluence (15-150 keV) : 2.29575e-06 ( -1.8769e-07 1.59881e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 3.220 sec. to 4.220 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.2392 ( -0.242983 0.248021 ) Norm@50keV : 1.00362E-02 ( -0.00137969 0.00137954 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 62.79 using 59 PHA bins. # Reduced chi-squared = 1.102 for 57 degrees of freedom # Null hypothesis probability = 2.785608e-01 Photon flux (15-150 keV) in 1 sec: 1.18497 ( -0.16957 0.1703 ) ph/cm2/s Energy fluence (15-150 keV) : 1.00742e-07 ( -1.5123e-08 1.52639e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.220 sec. to 4.220 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.830551 ( -0.532459 1.14769 ) Epeak [keV] : 156.459 ( -156.459 -156.459 ) Norm@50keV : 1.55470E-02 ( -0.00668174 0.0346775 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 62.25 using 59 PHA bins. # Reduced chi-squared = 1.112 for 56 degrees of freedom # Null hypothesis probability = 2.635974e-01 Photon flux (15-150 keV) in 1 sec: 1.16083 ( -0.179316 0.17884 ) ph/cm2/s Energy fluence (15-150 keV) : 3.39657e-08 ( -8.28836e-09 5.75711e-09 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 122.988 sec. Hardness ratio (energy fluence ratio) = 1.52834029288
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 8.039045e-07 S(50-150 keV) = 1.4782971e-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 = 3.476987868010762E-01, IMY = 1.262000909967558E-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: -239.944000 -150.520000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 244.9707 -15.6461 0.5 41.0 -10.6 4.5248 24.0 0.6 Sco X-1 256.2353 -37.8627 0.0 21.9 -41.2 0.0844 0.6 11.8 4U 1700-377 256.3166 -36.4666 6.7 22.1 -37.5 0.2377 1.7 6.3 GX 349+2 263.0222 -24.9504 0.0 22.1 -2.9 0.0406 0.3 12.3 GX 1+4 264.4586 -44.4523 8.0 16.1 -62.8 -0.1937 -1.4 12.2 4U 1735-44 268.1532 -1.4695 0.0 39.3 31.6 0.2320 1.0 12.9 SW J1753.5-0127 270.3531 -25.1237 5.8 17.3 11.0 0.2736 2.1 4.6 GX 5-1 270.3127 -25.5643 7.0 17.0 9.9 0.2317 1.8 10.7 GRS 1758-258 273.9598 -13.9827 5.4 25.6 34.0 0.3238 2.1 4.2 GX 17+2 275.6865 -30.3964 5.4 10.2 12.0 -0.2793 -2.1 12.5 H1820-303 285.1060 -25.0862 3.9 12.8 61.4 0.3940 3.0 10.6 HT1900.1-2455 263.0740 -33.6998 4.1 17.5 -25.2 -0.3564 -2.9 9.1 GX 354-0 251.8617 7.5511 2.1 54.5 16.8 3.8979 5.4 ------ UNKNOWN 295.7212 -26.2724 3.1 15.2 100.8 0.5128 3.7 ------ UNKNOWN 332.8590 -83.5212 2.9 48.0 -129.2 2.5345 4.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -150.520000 13.444000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 245.1474 -15.6692 5.7 40.8 -10.5 0.7749 2.0 9.9 Sco X-1 255.7940 -37.8720 3.9 22.3 -41.4 0.8230 3.0 9.3 4U 1700-377 256.2801 -36.4959 4.7 22.1 -37.6 0.6425 2.4 8.7 GX 349+2 262.8694 -24.7771 5.8 22.3 -2.7 0.5201 2.0 7.8 GX 1+4 264.5378 -44.5120 5.9 16.1 -63.1 0.5145 2.0 9.5 4U 1735-44 268.2389 -1.4208 5.8 39.3 31.8 -0.9528 -2.0 8.0 SW J1753.5-0127 270.2482 -24.8867 5.3 17.5 11.2 0.5707 2.2 11.7 GX 5-1 270.1785 -25.8371 3.5 16.9 9.0 0.8262 3.3 8.8 GRS 1758-258 273.9699 -13.8512 14.4 25.7 34.1 -0.2572 -0.8 11.3 GX 17+2 275.8124 -30.3369 5.5 10.2 12.7 0.5312 2.1 6.1 H1820-303 285.0991 -24.7807 6.2 13.1 61.3 0.4844 1.8 9.1 HT1900.1-2455 263.0490 -33.6782 4.0 17.6 -25.1 0.7210 2.9 9.9 GX 354-0 314.8426 -8.6224 2.6 40.3 108.7 4.7624 4.5 ------ UNKNOWN 265.6547 -26.6331 0.8 19.2 -2.1 3.9693 15.1 ------ UNKNOWN 249.3065 -15.8102 2.4 37.7 -6.4 1.5825 4.8 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 78.956610 424.056600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 244.9785 -15.6438 0.2 22.1 -61.0 21.8353 47.4 0.2 Sco X-1 256.0941 -37.9114 9.9 13.9 -143.4 0.4146 1.2 6.5 4U 1700-377 256.3320 -36.3633 3.9 12.6 -139.7 1.0584 3.0 6.1 GX 349+2 262.9440 -24.8980 6.8 3.0 -52.8 0.6521 1.7 9.8 GX 1+4 264.8666 -44.3202 12.3 17.8 -174.6 0.3192 0.9 9.4 4U 1735-44 268.4913 -1.3083 4.6 25.4 10.2 -0.9530 -2.5 11.4 SW J1753.5-0127 270.2355 -25.0761 3.8 4.4 74.8 1.0308 3.0 2.7 GX 5-1 270.4652 -25.7018 12.6 4.4 83.4 0.3154 1.0 9.1 GRS 1758-258 274.1553 -14.0126 5.1 14.9 37.6 0.8388 2.2 8.8 GX 17+2 275.9102 -30.3993 6.7 9.8 119.0 0.6479 1.7 2.1 H1820-303 284.9068 -25.0921 0.0 17.4 93.0 0.1560 0.4 12.5 HT1900.1-2455 288.9199 10.9844 6.8 43.8 37.6 1.5897 1.7 7.5 GRS 1915+105 262.8028 -33.6902 0.0 7.5 -158.1 0.7743 2.0 12.7 GX 354-0 282.3330 8.9940 3.4 39.1 30.3 2.1927 3.4 ------ UNKNOWN 277.4194 15.9895 2.2 44.1 19.9 3.6941 5.3 ------ UNKNOWN 284.9384 -30.4398 2.8 17.4 111.0 1.5898 4.1 ------ UNKNOWN 275.1136 7.1620 2.1 34.9 20.1 2.8455 5.4 ------ UNKNOWN 243.3196 25.6923 3.0 56.5 -20.7 5.7389 3.9 ------ UNKNOWN