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: Thu Mar 21 13:35:48 EDT 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger889748
======================================================================
Trigger: 00889748 Segment: 000
BAT Trigger Time: 572297960.448 [s; MET]
Trigger Stop: 572297964.544 [s; MET]
UTC: 2019-02-19T19:38:58.002900 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 189.757083789005 Dec: 76.6139916242753 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 10.13
Image Trigger?: NO
Rate S/N Ratio: 8.54400374531753 [ if not an image trigger ]
Image S/N Ratio: 10.13
Analysis Position: [ source = BAT ]
RA: 189.757083789005 Dec: 76.6139916242753 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 189.689543805993 Dec: 76.6071023927069 [deg; J2000]
{ 12h 38m 45.5s , +76d 36' 25.6" }
+/- 1.63188274752761 [arcmin] (estimated 90% radius based on SNR)
+/- 0.720827480316864 [arcmin] (formal 1-sigma fit error)
SNR: 15.1104368914486
Angular difference between the analysis and refined position is 1.025414 arcmin
Partial Coding Fraction: 0.765625 [ including projection effects ]
Duration
T90: 167.739999890327 +/- 12.7941918627511
Measured from: -89.3319998979568
to: 78.4079999923706 [s; relative to TRIGTIME]
T50: 62.5080000162125 +/- 2.4526133393256
Measured from: 3.68400001525879
to: 66.1920000314713 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 65.5240000486374
to: 66.5240000486374 [s; relative to TRIGTIME]
Total Fluence
Measured from: -105.740000009537
to: 88.4960000514984 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 3.146041 2.930655 1.261988 0.279404
0.108649 0.112020 0.095600 0.083857 [error]
Peak 0.092585 0.088123 0.029180 0.007747
0.008226 0.008302 0.006664 0.005296 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 194.236 -105.740 88.496
T90 167.740 -89.332 78.408
T50 62.508 3.684 66.192
Peak 1.000 65.524 66.524
====== 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 -2.214 -0.105 0.102 - - - 2.08e-03 -1.32e-04 1.30e-04 49.040 57
CPL -2.213 -0.107 0.100 10000.000 -10000.000 -10000.000 2.08e-03 -1.01e-04 1.28e-04 49.060 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 -2.119 -0.212 0.199 - - - 1.12e-02 -1.66e-03 1.62e-03 60.530 57
CPL -1.648 -0.414 1.165 28.683 N/A N/A 2.18e-02 N/A N/A 59.740 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 1.01e-06 1.21e-06 1.04e-06 1.53e-06 3.80e-06 4.79e-06 erg/cm2
90%_error_low -7.55e-08 -5.85e-08 -9.22e-08 -2.58e-07 -2.06e-07 -3.59e-07 erg/cm2
90%_error_hi 7.72e-08 5.85e-08 9.36e-08 2.94e-07 2.08e-07 3.83e-07 erg/cm2
Peak flux PL 8.35e-01 5.84e-01 2.69e-01 1.73e-01 1.77e+00 1.86e+00 ph/cm2/s
90%_error_low -1.21e-01 -6.44e-02 -5.15e-02 -5.51e-02 -1.92e-01 -2.04e-01 ph/cm2/s
90%_error_hi 1.24e-01 6.42e-02 5.28e-02 6.91e-02 1.92e-01 2.04e-01 ph/cm2/s
Fluence CPL 9.65e-07 1.25e-06 1.02e-06 7.60e-07 3.64e-06 4.00e-06 erg/cm2
90%_error_low -8.82e-08 -7.12e-08 -1.04e-07 -3.55e-07 -2.51e-07 -4.55e-07 erg/cm2
90%_error_hi 8.58e-08 7.47e-08 1.02e-07 5.09e-07 2.54e-07 6.47e-07 erg/cm2
Peak flux CPL 8.14e-01 6.20e-01 2.60e-01 8.19e-02 1.75e+00 1.78e+00 ph/cm2/s
90%_error_low -1.31e-01 -8.44e-02 -6.96e-02 -8.19e-02 -1.97e-01 -2.13e-01 ph/cm2/s
90%_error_hi 1.30e-01 9.76e-02 5.87e-02 1.74e-01 1.96e-01 2.41e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 189.6895 76.6071 0.0127 26.9185 -142.9218 3.9692595 15.110 TRIG_00889748 Foreground time interval of the image: -105.740 35.653 (delta_t = 141.393 [sec]) Background time interval of the image: -239.448 -105.740 (delta_t = 133.708 [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 -105.740 sec. to 88.496 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.21422 ( -0.104605 0.101869 ) Norm@50keV : 2.07737E-03 ( -0.000131507 0.000129997 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 49.04 using 59 PHA bins. # Reduced chi-squared = 0.8603 for 57 degrees of freedom # Null hypothesis probability = 7.643119e-01 Photon flux (15-150 keV) in 194.2 sec: 0.346542 ( -0.017456 0.017498 ) ph/cm2/s Energy fluence (15-150 keV) : 3.80154e-06 ( -2.06042e-07 2.08041e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -105.740 sec. to 88.496 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.21264 ( -0.106925 0.100277 ) Epeak [keV] : 1.00000E+04 ( -10000 -10000 ) Norm@50keV : 2.07761E-03 ( -0.000100578 0.000128894 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 49.06 using 59 PHA bins. # Reduced chi-squared = 0.8760 for 56 degrees of freedom # Null hypothesis probability = 7.329545e-01 Photon flux (15-150 keV) in 194.2 sec: 0.337678 ( -0.019312 0.019189 ) ph/cm2/s Energy fluence (15-150 keV) : 3.6384e-06 ( -2.5113e-07 2.5393e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 65.524 sec. to 66.524 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -2.11879 ( -0.212409 0.19907 ) Norm@50keV : 1.11586E-02 ( -0.00166147 0.00162228 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 60.53 using 59 PHA bins. # Reduced chi-squared = 1.062 for 57 degrees of freedom # Null hypothesis probability = 3.497084e-01 Photon flux (15-150 keV) in 1 sec: 1.77215 ( -0.19172 0.19171 ) ph/cm2/s Energy fluence (15-150 keV) : 1.03891e-07 ( -1.37069e-08 1.40025e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 65.524 sec. to 66.524 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.64772 ( -0.415662 1.16296 ) Epeak [keV] : 28.6833 ( ) Norm@50keV : 2.17512E-02 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 59.74 using 59 PHA bins. # Reduced chi-squared = 1.067 for 56 degrees of freedom # Null hypothesis probability = 3.414947e-01 Photon flux (15-150 keV) in 1 sec: 1.75036 ( -0.19661 0.19624 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 167.74 sec. Hardness ratio (energy fluence ratio) = 0.862064339389
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 2.219624e-06 S(50-150 keV) = 1.5819619e-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 = -4.050769346816848E-01, IMY = 3.061155258480396E-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: -239.448000 -105.740000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] [']
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -105.740000 35.652590 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 189.6895 76.6071 0.8 26.9 -142.9 3.9688 15.1 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 89.652610 962.711300 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 254.4200 35.3473 5.0 49.9 -23.5 3.4155 2.3 1.9 Her X-1 227.4583 25.8679 2.6 53.9 8.0 8.4344 4.3 ------ UNKNOWN 272.6815 39.5012 3.1 50.2 -43.2 11.8160 3.8 ------ UNKNOWN