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 v2.48
Process Start Time: Wed Sep 9 23:02:24 EDT 2020
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger981957
======================================================================
Trigger: 00981957 Segment: 000
BAT Trigger Time: 616158301.76 [s; MET]
Trigger Stop: 616158302.784 [s; MET]
UTC: 2020-07-11T11:04:36.495000 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 285.976650447479 Dec: -0.136296528746014 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 6.78
Image Trigger?: NO
Rate S/N Ratio: 65.9621103361619 [ if not an image trigger ]
Image S/N Ratio: 6.78
Analysis Position: [ source = BAT ]
RA: 285.976650447479 Dec: -0.136296528746014 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 285.974051212983 Dec: -0.134789313063288 [deg; J2000]
{ 19h 03m 53.8s , -00d 08' 05.2" }
+/- 1.47543784963379 [arcmin] (estimated 90% radius based on SNR)
+/- 0.755725633300015 [arcmin] (formal 1-sigma fit error)
SNR: 17.4502952571786
Angular difference between the analysis and refined position is 0.180277 arcmin
Partial Coding Fraction: 0.08691406 [ including projection effects ]
Duration
T90: 29.3600000143051 +/- 3.07170836177462
Measured from: -3.26399993896484
to: 26.0960000753403 [s; relative to TRIGTIME]
T50: 16.960000038147 +/- 1.53101285943251
Measured from: -0.25600004196167
to: 16.7039999961853 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.195999979972839
to: 1.19599997997284 [s; relative to TRIGTIME]
Total Fluence
Measured from: -4.72000002861023
to: 29.7280000448227 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 1.959453 2.864675 2.427948 0.678822
0.153755 0.161666 0.144052 0.117082 [error]
Peak 0.146726 0.390617 0.345471 0.135351
0.036365 0.041097 0.042464 0.035365 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 34.448 -4.720 29.728
T90 29.360 -3.264 26.096
T50 16.960 -0.256 16.704
Peak 1.000 0.196 1.196
====== 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 -1.414 -0.104 0.104 - - - 1.59e-02 -9.51e-04 9.50e-04 55.780 57
CPL -1.094 -0.363 0.440 152.810 -59.314 -152.810 2.25e-02 -7.12e-03 1.34e-02 53.940 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: N/A)
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 -1.123 -0.206 0.209 - - - 6.63e-02 -8.48e-03 8.48e-03 62.810 57
CPL -0.121 -0.876 1.117 99.876 -27.865 267.911 2.01e-01 -1.23e-01 4.77e-01 58.890 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 6.45e-07 1.25e-06 1.88e-06 6.09e-06 5.28e-06 9.86e-06 erg/cm2
90%_error_low -7.02e-08 -8.35e-08 -1.37e-07 -9.26e-07 -3.40e-07 -1.03e-06 erg/cm2
90%_error_hi 7.28e-08 8.31e-08 1.37e-07 1.03e-06 3.41e-07 1.11e-06 erg/cm2
Peak flux PL 4.51e-04 6.92e-03 7.63e-02 6.81e+00 2.61e-01 6.82e+00 ph/cm2/s
90%_error_low 3.32e-05 -9.08e-04 -8.49e-03 -9.03e-01 4.62e-02 -8.40e-01 ph/cm2/s
90%_error_hi 3.72e-04 2.76e-03 2.95e-02 1.64e+00 2.09e-01 1.76e+00 ph/cm2/s
Fluence CPL 5.18e-07 7.17e-07 7.68e-07 1.88e-06 2.51e-06 3.88e-06 erg/cm2
90%_error_low -3.31e-08 -3.17e-07 -1.36e-07 -1.73e-07 -4.60e-07 -5.51e-07 erg/cm2
90%_error_hi 7.55e-08 7.21e-08 1.25e-07 1.75e-07 4.49e-06 4.98e-07 erg/cm2
Peak flux CPL 1.54e+00 2.60e+00 2.44e+00 1.42e+00 7.48e+00 8.00e+00 ph/cm2/s
90%_error_low -4.99e-01 -4.20e-01 -3.89e-01 -7.91e-01 -1.02e+00 -1.31e+00 ph/cm2/s
90%_error_hi 5.44e-01 4.38e-01 4.02e-01 1.72e+00 1.02e+00 1.84e+00 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 285.9741 -0.1348 0.0111 38.8815 99.0328 5.6639932 17.450 TRIG_00981957 Foreground time interval of the image: -4.720 12.541 (delta_t = 17.261 [sec]) Background time interval of the image: -239.760 -4.720 (delta_t = 235.040 [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 -4.720 sec. to 29.728 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.41368 ( -0.104275 0.10433 ) Norm@50keV : 1.58911E-02 ( -0.000950656 0.000950244 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 55.78 using 59 bins. Reduced chi-squared = 0.978596 # Null hypothesis probability of 5.21e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 34.45 sec: 1.94137 ( -0.12232 0.12259 ) ph/cm2/s Energy fluence (15-150 keV) : 5.27595e-06 ( -3.39675e-07 3.40726e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.720 sec. to 29.728 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.0936 ( -0.362882 0.439506 ) Epeak [keV] : 152.810 ( -59.3132 -152.81 ) Norm@50keV : 2.25422E-02 ( -0.00712475 0.0133557 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 53.94 using 59 bins. Reduced chi-squared = 0.963214 # Null hypothesis probability of 5.53e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 34.45 sec: 1.91208 ( -0.12759 0.12774 ) ph/cm2/s Energy fluence (15-150 keV) : 2.50639e-06 ( -4.60187e-07 4.49476e-06 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.196 sec. to 1.196 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.12337 ( -0.205951 0.208574 ) Norm@50keV : 6.62785E-02 ( -0.00847921 0.00847891 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 62.81 using 59 bins. Reduced chi-squared = 1.10193 # Null hypothesis probability of 2.78e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 0.260764 ( 0.046159 0.209152 ) ph/cm2/s Energy fluence (15-150 keV) : 6.87939e-07 ( -9.72621e-08 9.80745e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.196 sec. to 1.196 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.120707 ( -0.875767 1.11745 ) Epeak [keV] : 99.8760 ( -27.8643 267.911 ) Norm@50keV : 0.200694 ( -0.122786 0.477005 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 58.89 using 59 bins. Reduced chi-squared = 1.05161 # Null hypothesis probability of 3.70e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 7.47820 ( -1.02255 1.02361 ) ph/cm2/s Energy fluence (15-150 keV) : 6.49935e-07 ( -1.07659e-07 1.0648e-07 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 29.36 sec. Hardness ratio (energy fluence ratio) = 1.50144680142
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 1.8936941e-06 S(50-150 keV) = 3.382167e-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 = -1.265991246325264E-01, IMY = -7.963656060771516E-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: -239.760000 -4.720000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 255.9618 -37.8590 1.5 44.2 25.9 4.4540 7.8 1.5 4U 1700-377 256.4958 -36.4453 4.3 44.1 28.0 1.6082 2.7 3.2 GX 349+2 262.8716 -24.6692 16.1 41.8 46.9 0.5026 0.7 8.8 GX 1+4 264.7212 -44.4878 3.4 37.4 16.2 -1.4650 -3.4 2.4 4U 1735-44 270.3692 -25.0877 4.4 35.3 50.0 -1.4456 -2.6 4.7 GX 5-1 270.2699 -25.6981 3.8 35.2 49.0 1.6620 3.1 3.2 GRS 1758-258 273.8809 -14.0736 10.5 37.4 69.2 -0.7643 -1.1 7.6 GX 17+2 276.1363 -30.4093 0.0 29.0 43.0 -0.6930 -1.9 11.2 H1820-303 284.9970 -24.7991 5.6 23.0 60.5 0.6781 2.1 7.6 HT1900.1-2455 263.0172 -33.6867 6.6 39.3 33.6 -0.9356 -1.8 9.0 GX 354-0 356.2436 4.8672 3.4 57.2 -161.6 5.9551 3.4 368.7 UNKNOWN 283.0635 -74.2808 4.0 44.7 -30.4 1.4429 2.9 ------ UNKNOWN 354.7084 -7.0685 2.8 48.3 -151.3 2.9547 4.1 529.3 UNKNOWN 229.2516 -73.6596 2.6 57.2 -21.2 5.3905 4.4 ------ UNKNOWN 353.7833 -26.2063 2.7 38.4 -127.2 2.3398 4.3 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -4.720000 12.540600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 255.9839 -37.8433 352.4 44.2 26.0 -0.0058 -0.0 0.1 4U 1700-377 256.5291 -36.5178 8.8 44.0 28.0 0.2448 1.3 7.3 GX 349+2 262.9366 -24.9522 13.6 41.7 46.5 -0.2056 -0.8 13.0 GX 1+4 264.7011 -44.5463 6.0 37.4 16.1 0.2149 1.9 6.0 4U 1735-44 270.3323 -25.0583 4.3 35.4 50.1 0.3795 2.7 2.9 GX 5-1 270.1944 -25.8568 23.5 35.2 48.7 0.0661 0.5 9.0 GRS 1758-258 273.9918 -14.1788 167.1 37.3 69.1 0.0156 0.1 8.6 GX 17+2 276.0599 -30.4562 6.5 29.0 42.9 0.1682 1.8 8.8 H1820-303 285.0098 -25.1307 0.0 22.9 59.8 0.0919 1.1 12.7 HT1900.1-2455 263.0941 -33.6368 0.0 39.2 33.7 -0.1304 -0.9 13.0 GX 354-0 285.9742 -0.1349 0.7 38.9 99.0 5.6935 17.3 ------ UNKNOWN 266.3600 -52.7351 3.4 37.8 2.6 0.3053 3.4 ------ UNKNOWN 266.5791 -53.3665 3.2 37.8 1.5 0.3193 3.5 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 147.740600 837.836500 900.240000 962.304300 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 244.9728 -15.6245 0.7 43.4 170.1 29.2401 16.7 1.0 Sco X-1 255.9877 -37.8633 2.9 46.8 135.9 13.7272 4.0 1.2 4U 1700-377 256.5677 -36.5288 10.0 45.5 136.7 -3.4182 -1.1 9.0 GX 349+2 263.0084 -24.7457 10.4 33.2 143.5 1.4592 1.1 0.0 GX 1+4 268.2659 -1.4306 5.3 17.9 -171.2 -1.7655 -2.2 6.3 SW J1753.5-0127 270.2182 -25.2269 13.4 29.4 133.2 1.1342 0.9 9.6 GX 5-1 270.2437 -25.7416 5.5 29.8 132.6 2.9659 2.2 3.2 GRS 1758-258 274.1884 -14.1513 43.3 18.3 142.5 -0.2346 -0.3 12.7 GX 17+2 275.9245 -30.3656 8.2 31.7 119.8 2.0453 1.4 0.1 H1820-303 285.2249 -25.0380 0.0 24.9 104.8 -0.7213 -0.6 12.5 HT1900.1-2455 288.7699 11.0361 24.0 11.5 -63.6 0.4221 0.5 5.7 GRS 1915+105 299.5684 35.2047 3.2 37.5 -58.8 6.3482 3.6 1.1 Cyg X-1 308.1294 40.8152 19.9 45.6 -53.6 2.1930 0.6 8.3 Cyg X-3 262.8325 -33.8611 16.8 40.1 133.5 1.6711 0.7 8.0 GX 354-0 323.8194 4.6316 3.1 38.0 5.3 4.6211 3.7 ------ UNKNOWN 251.0082 29.8059 3.4 44.9 -122.0 11.8314 3.4 ------ UNKNOWN 244.8921 27.0491 3.4 48.0 -129.1 15.4721 3.4 ------ UNKNOWN