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: Fri Oct 19 18:41:40 EDT 2018
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger853824
======================================================================
Trigger: 00853824 Segment: 000
BAT Trigger Time: 556254745.472 [s; MET]
Trigger Stop: 556254747.52 [s; MET]
UTC: 2018-08-18T03:12:04.026320 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 169.611178716171 Dec: -48.3444485884011 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 7.09
Image Trigger?: NO
Rate S/N Ratio: 8.30662386291807 [ if not an image trigger ]
Image S/N Ratio: 7.09
Analysis Position: [ source = BAT ]
RA: 169.611178716171 Dec: -48.3444485884011 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 169.697910172213 Dec: -48.3441283355387 [deg; J2000]
{ 11h 18m 47.5s , -48d 20' 38.9" }
+/- 2.25807854736247 [arcmin] (estimated 90% radius based on SNR)
+/- 0.878051906165051 [arcmin] (formal 1-sigma fit error)
SNR: 9.50116559434281
Angular difference between the analysis and refined position is 3.458833 arcmin
Partial Coding Fraction: 0.7890625 [ including projection effects ]
Duration
T90: 13.7120000123978 +/- 4.05053675162408
Measured from: -1.60000002384186
to: 12.1119999885559 [s; relative to TRIGTIME]
T50: 5.91999995708466 +/- 2.40474200278857
Measured from: 1.18400001525879
to: 7.10399997234344 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 1.6360000371933
to: 2.6360000371933 [s; relative to TRIGTIME]
Total Fluence
Measured from: -2.14400005340576
to: 14.095999956131 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 0.229433 0.192534 0.073955 0.051671
0.030013 0.030679 0.026773 0.024796 [error]
Peak 0.035751 0.036374 0.004326 0.007113
0.007672 0.008122 0.006910 0.006202 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 16.240 -2.144 14.096
T90 13.712 -1.600 12.112
T50 5.920 1.184 7.104
Peak 1.000 1.636 2.636
====== 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 -2.153 -0.380 0.334 - - - 1.70e-03 -4.31e-04 4.13e-04 47.850 57
CPL -1.994 1.994 1.994 1.737 N/A N/A 2.08e-03 N/A N/A 47.990 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 -2.112 -0.585 0.494 - - - 4.04e-03 -1.64e-03 1.60e-03 70.930 57
CPL 0.395 -2.642 4.678 32.544 -32.544 -32.544 1.75e-01 -1.75e-01 2.49e+02 68.780 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 6.53e-08 8.08e-08 7.27e-08 1.13e-07 2.58e-07 3.32e-07 erg/cm2
90%_error_low -1.41e-08 -1.43e-08 -2.42e-08 -5.97e-08 -5.47e-08 -9.32e-08 erg/cm2
90%_error_hi 1.44e-08 1.40e-08 2.59e-08 9.37e-08 5.76e-08 1.20e-07 erg/cm2
Peak flux PL 3.01e-01 2.11e-01 9.77e-02 6.33e-02 6.40e-01 6.73e-01 ph/cm2/s
90%_error_low -1.04e-01 -6.29e-02 -4.78e-02 -6.33e-02 -1.81e-01 -1.95e-01 ph/cm2/s
90%_error_hi 1.07e-01 6.17e-02 5.35e-02 8.02e-02 1.81e-01 1.98e-01 ph/cm2/s
Fluence CPL 6.40e-08 N/A 6.59e-08 8.40e-08 2.55e-07 2.96e-07 erg/cm2
90%_error_low N/A -1.43e-08 N/A N/A -6.37e-08 N/A erg/cm2
90%_error_hi N/A 1.40e-08 N/A N/A 6.22e-08 N/A erg/cm2
Peak flux CPL 2.78e-01 2.75e-01 6.05e-02 1.56e-03 6.15e-01 6.15e-01 ph/cm2/s
90%_error_low -1.20e-01 -9.44e-02 -6.05e-02 -1.56e-03 -1.71e-01 -1.71e-01 ph/cm2/s
90%_error_hi 1.18e-01 9.66e-02 7.01e-02 9.30e-02 1.74e-01 1.74e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 169.6979 -48.3441 0.0202 15.9361 80.3643 0.5702285 9.501 TRIG_00853824 Foreground time interval of the image: -2.144 14.096 (delta_t = 16.240 [sec]) Background time interval of the image: -239.472 -2.144 (delta_t = 237.328 [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 -2.144 sec. to 14.096 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.15339 ( -0.379878 0.333913 ) Norm@50keV : 1.69910E-03 ( -0.000430791 0.00041257 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 47.85 using 59 PHA bins. # Reduced chi-squared = 0.8395 for 57 degrees of freedom # Null hypothesis probability = 8.006667e-01 Photon flux (15-150 keV) in 16.24 sec: 0.274603 ( -0.044615 0.044623 ) ph/cm2/s Energy fluence (15-150 keV) : 2.57914e-07 ( -5.46567e-08 5.75836e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.144 sec. to 14.096 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.34121 ( 1.99395 1.99395 ) Epeak [keV] : 136.642 ( ) Norm@50keV : 1.33115E-03 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 47.69 using 59 PHA bins. # Reduced chi-squared = 0.8515 for 56 degrees of freedom # Null hypothesis probability = 7.776592e-01 Photon flux (15-150 keV) in 16.24 sec: 0.255793 ( ) ph/cm2/s Energy fluence (15-150 keV) : 2.54822e-07 ( -6.36843e-08 6.21977e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.636 sec. to 2.636 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.11166 ( -0.585139 0.493693 ) Norm@50keV : 4.04425E-03 ( -0.00164071 0.00160402 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 70.93 using 59 PHA bins. # Reduced chi-squared = 1.244 for 57 degrees of freedom # Null hypothesis probability = 1.015116e-01 Photon flux (15-150 keV) in 1 sec: 0.640009 ( -0.180656 0.1809 ) ph/cm2/s Energy fluence (15-150 keV) : 3.76279e-08 ( -1.31604e-08 1.43609e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.636 sec. to 2.636 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: 0.395312 ( -2.67701 4.64355 ) Epeak [keV] : 32.5443 ( -32.5644 -32.5644 ) Norm@50keV : 0.174593 ( -0.199967 248.605 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 68.78 using 59 PHA bins. # Reduced chi-squared = 1.228 for 56 degrees of freedom # Null hypothesis probability = 1.172913e-01 Photon flux (15-150 keV) in 1 sec: 0.615221 ( -0.170834 0.173932 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 13.712 sec. Hardness ratio (energy fluence ratio) = 0.899166270383
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 1.4616185e-07 S(50-150 keV) = 1.1175106e-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 = 4.779451202660808E-02, IMY = -2.815104026009791E-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: -239.472000 -2.144000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5526 -40.5448 0.8 18.0 177.7 3.4230 15.0 1.2 Vela X-1 170.4145 -60.6361 4.2 26.7 97.1 0.9920 2.8 3.0 Cen X-3 186.6603 -62.5897 21.9 32.8 86.8 0.2588 0.5 10.8 GX 301-2 168.6034 0.1516 2.4 36.9 -49.8 2.0332 4.8 ------ UNKNOWN 160.5546 8.3683 3.0 43.7 -64.2 5.0247 3.8 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -2.144000 14.096000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.6068 -40.4961 3.4 18.0 177.8 -0.1762 -3.4 5.0 Vela X-1 170.2239 -60.6724 9.4 26.7 97.4 -0.0983 -1.2 4.0 Cen X-3 186.4406 -62.6574 8.7 32.8 87.0 0.1427 1.3 9.0 GX 301-2 169.6979 -48.3441 1.2 15.9 80.4 0.5702 9.5 ------ UNKNOWN 171.1543 -15.7785 2.0 23.0 -32.9 0.3265 5.8 ------ UNKNOWN 173.4105 10.3364 1.9 48.0 -47.3 1.0710 6.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 63.428590 716.676000 720.528000 962.563200 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5322 -40.5521 0.7 25.3 -150.7 13.5147 15.7 0.2 Vela X-1 170.1735 -60.6090 1.4 12.3 112.9 5.6313 8.4 4.3 Cen X-3 186.6882 -62.7223 3.0 17.2 87.2 2.7938 3.8 3.0 GX 301-2 230.9387 -67.4912 2.9 35.7 79.1 6.1901 4.0 ------ UNKNOWN 217.5579 -37.2611 3.5 36.2 24.7 3.0750 3.3 ------ UNKNOWN 83.7368 -43.9807 3.1 56.4 173.7 18.7715 3.7 ------ UNKNOWN 219.3931 -18.2742 2.7 50.1 5.3 6.0944 4.3 ------ UNKNOWN 96.0097 -35.3509 2.6 54.2 -171.0 10.7730 4.5 ------ UNKNOWN 204.7309 -12.5777 2.5 46.1 -14.5 5.2215 4.7 ------ UNKNOWN 101.9851 -35.2037 3.8 50.4 -167.1 5.8001 3.1 ------ UNKNOWN 169.1084 -16.1114 3.0 32.2 -66.6 4.6215 3.9 ------ UNKNOWN 204.1547 2.3753 3.5 58.9 -24.3 14.0974 3.3 ------ UNKNOWN 178.0384 -2.0611 3.4 46.8 -54.2 13.0512 3.3 ------ UNKNOWN 120.0833 -16.9293 3.5 50.9 -135.4 16.9585 3.3 ------ UNKNOWN