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 GROUND-DETECTED GRB DATA PROCESSING REPORT
Process Script Ver: batgrbproduct v2.47
Process Start Time: Tue Aug 11 21:44:09 EDT 2020
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
======================================================================
Trigger: 00987745 Segment: 000
BAT Trigger Time: 618680512.4200001
UTC: 20200809T15:41:26.928 [includes UTCF correction]
Where From?: Ground analysis (best_duration.txt)
NOTE: BAT trigger time for ground-detected burst is the T100 start time.
Analysis Position: [ source = GCN ]
RA: 00013289073; Dec: GUANO [deg; J2000]
Refined Position: [ source = BAT pre-slew image ]
RA: 15.887882008057375 Dec: -73.83023981306451 [deg; J2000]
{ 01h 03m 33.1s , -73d -49' -48.9" }
+/- 2.03040714 [arcmin] (estimated 90% radius based on SNR)
SNR: 11.06039719593009
Angular difference between the analysis and refined position is 4473.860892 arcmin
Partial Coding Fraction: 0.2402344 [ including projection effects ]
Duration
T90: 4.20000004768372 +/- 0.627808900355524
Measured from: 0.084
to: 4.284 [s; relative to TRIGTIME]
T50: 2.44799995422363 +/- 0.785073261584158
Measured from: 0.424
to: 2.872 [s; relative to TRIGTIME]
====== Table of the duration information =============================
Value tstart tstop
T100 4.508 0.000 4.508
T90 4.200 0.084 4.284
T50 2.448 0.424 2.872
Peak 1.000 -0.004 0.996
====== 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 -1.156 -0.303 0.317 - - - 8.99e-03 -1.42e-03 1.41e-03 67.050 57
CPL -1.173 -1.157 0.254 9999.360 N/A N/A 9.05e-03 N/A N/A 67.080 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 -0.900 -0.392 0.427 - - - 1.75e-02 -3.71e-03 3.53e-03 52.620 57
CPL -0.916 -5.939 0.782 9999.360 N/A N/A 1.77e-02 N/A N/A 52.650 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 3.75e-08 8.52e-08 1.53e-07 6.48e-07 4.16e-07 9.23e-07 erg/cm2
90%_error_low -1.23e-08 -1.74e-08 -2.75e-08 -2.41e-07 -6.92e-08 -2.58e-07 erg/cm2
90%_error_hi 1.38e-08 1.66e-08 2.67e-08 3.32e-07 6.94e-08 3.35e-07 erg/cm2
Peak flux PL 4.07e-01 5.87e-01 6.29e-01 1.25e+00 2.01e+00 2.88e+00 ph/cm2/s
90%_error_low -1.80e-01 -1.72e-01 -1.27e-01 -5.20e-01 -4.12e-01 -5.95e-01 ph/cm2/s
90%_error_hi 2.19e-01 1.63e-01 1.24e-01 7.47e-01 4.15e-01 6.60e-01 ph/cm2/s
Fluence CPL 3.76e-08 8.53e-08 1.47e-07 6.43e-07 4.16e-07 8.95e-07 erg/cm2
90%_error_low -1.24e-08 -1.75e-08 N/A -3.18e-07 N/A -3.03e-07 erg/cm2
90%_error_hi 1.38e-08 1.65e-08 N/A 3.29e-07 N/A 3.37e-07 erg/cm2
Peak flux CPL 4.07e-01 5.87e-01 6.29e-01 1.24e+00 2.01e+00 2.89e+00 ph/cm2/s
90%_error_low N/A -1.72e-01 N/A N/A -4.13e-01 -7.60e-01 ph/cm2/s
90%_error_hi N/A 1.63e-01 N/A N/A 4.14e-01 6.34e-01 ph/cm2/s
======================================================================
Image
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.
Best duration plot
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 -0.000 sec. to 4.508 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.15645 ( -0.303433 0.316615 ) Norm@50keV : 8.98661E-03 ( -0.00142471 0.00141194 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 67.05 using 59 bins. Reduced chi-squared = 1.17632 # Null hypothesis probability of 1.70e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 4.508 sec: 1.04883 ( -0.176228 0.17723 ) ph/cm2/s Energy fluence (15-150 keV) : 4.16288e-07 ( -6.91726e-08 6.93962e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.000 sec. to 4.508 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.24188 ( -0.0877564 1.32292 ) Epeak [keV] : 84.8963 ( ) Norm@50keV : 1.80965E-03 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 65.33 using 59 bins. Reduced chi-squared = 1.16661 # Null hypothesis probability of 1.84e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 4.508 sec: 1.04870 ( -0.176325 0.17713 ) ph/cm2/s Energy fluence (15-150 keV) : 4.16068e-07 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.004 sec. to 0.996 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.900227 ( -0.391646 0.427309 ) Norm@50keV : 1.75196E-02 ( -0.00370618 0.00352838 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 52.62 using 59 bins. Reduced chi-squared = 0.923158 # Null hypothesis probability of 6.40e-01 with 57 degrees of freedom Photon flux (15-150 keV) in 1 sec: 2.01083 ( -0.41191 0.41508 ) ph/cm2/s Energy fluence (15-150 keV) : 1.96621e-07 ( -4.00865e-08 4.02053e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.004 sec. to 0.996 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.27164 ( -4.58379 2.13695 ) Epeak [keV] : 90.3516 ( ) Norm@50keV : 1.65591E-03 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared 52.04 using 59 bins. Reduced chi-squared = 0.929286 # Null hypothesis probability of 6.26e-01 with 56 degrees of freedom Photon flux (15-150 keV) in 1 sec: 2.01146 ( -0.41315 0.4138 ) ph/cm2/s Energy fluence (15-150 keV) : 2.3608e-08 ( 0 0 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 4.2 sec. Hardness ratio (energy fluence ratio) = 1.7945677877
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 1.2268949e-07 S(50-150 keV) = 2.935963e-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.
Spacecraft aspect plot
Bright source in the event data image
Event data image of 15-350 keV band
Time interval of the image: 0.000000 4.508000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.3788 -40.6099 4.8 42.8 -114.9 -0.2425 -2.4 7.6 Vela X-1 170.7325 -60.6445 3.3 13.5 -118.9 -0.0896 -3.5 12.3 Cen X-3 186.6427 -62.5806 6.3 5.7 -119.2 -0.0456 -1.8 11.4 GX 301-2 256.1217 -37.9470 3.3 42.0 56.5 0.3122 3.5 8.9 4U 1700-377 256.5100 -36.4807 10.5 43.4 55.7 -0.1087 -1.1 5.0 GX 349+2 264.6542 -44.6085 98.8 40.7 70.4 -0.0123 -0.1 10.2 4U 1735-44 15.8879 -73.8302 1.0 43.4 153.7 0.6427 11.1 ------ UNKNOWN 106.8107 -69.5657 2.9 34.2 -166.7 0.1191 4.0 ------ UNKNOWN 191.6038 -7.9926 2.8 55.0 -34.0 0.5492 4.1 ------ UNKNOWN
Webpage updated on: Mon Nov 16 15:18:19 EST 2020