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: Tue Jan 15 16:16:27 EST 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/prebascript/trigger883832/GCN5_download_cron
======================================================================
Trigger: 00883832 Segment: 000
BAT Trigger Time: 569192245.44 [s; MET]
Trigger Stop: 569192245.696 [s; MET]
UTC: 2019-01-14T20:57:03.190000 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 54.5096952529563 Dec: -26.938758821296 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 25.36
Image Trigger?: NO
Rate S/N Ratio: 255.998046867549 [ if not an image trigger ]
Image S/N Ratio: 25.36
Analysis Position: [ source = BAT ]
RA: 54.5096952529563 Dec: -26.938758821296 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 54.502995751585 Dec: -26.9381939583958 [deg; J2000]
{ 03h 38m 00.7s , -26d 56' 17.5" }
+/- 0.396807980535716 [arcmin] (estimated 90% radius based on SNR)
+/- 0.128872026770839 [arcmin] (formal 1-sigma fit error)
SNR: 113.91343664008
Angular difference between the analysis and refined position is 0.359953 arcmin
Partial Coding Fraction: 1.015625 [ including projection effects ]
Duration
T90: 361.459999918938 +/- 11.7360333432713
Measured from: 0.288000106811523
to: 361.748000025749 [s; relative to TRIGTIME]
T50: 49.0719999074936 +/- 1.47339065076633
Measured from: 3.14400005340576
to: 52.2159999608994 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 0.23199999332428
to: 1.23199999332428 [s; relative to TRIGTIME]
Total Fluence
Measured from: -6.60400009155273
to: 703.191999912262 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 41.600422 48.878760 36.983300 11.459671
0.197109 0.209919 0.194058 0.178226 [error]
Peak 2.324999 4.294172 4.863500 1.830169
0.026597 0.036545 0.041352 0.033084 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 709.412 -6.604 702.808
T90 374.724 0.260 374.984
T50 55.648 3.684 59.332
Peak 1.000 0.232 1.232
====== 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: 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 -1.431 -0.024 0.025 - - - 1.21e-02 -1.58e-04 1.57e-04 90.470 57
CPL -1.430 -0.022 0.028 9999.360 -9999.360 -9999.360 1.21e-02 -1.66e-04 1.31e-04 91.540 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 -0.886 -0.027 0.027 - - - 8.79e-01 -1.33e-02 1.32e-02 33.630 57
CPL -0.807 -0.030 0.042 998.129 -998.129 -998.129 9.42e-01 -6.99e-02 -1.70e-02 37.310 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 1.02e-05 1.96e-05 2.91e-05 9.29e-05 8.21e-05 1.52e-04 erg/cm2
90%_error_low -3.18e-07 -3.57e-07 -3.45e-07 -2.78e-06 -9.51e-07 -2.71e-06 erg/cm2
90%_error_hi 3.23e-07 3.57e-07 3.44e-07 2.84e-06 9.51e-07 2.76e-06 erg/cm2
Peak flux PL 2.01e+01 2.93e+01 3.17e+01 6.41e+01 1.01e+02 1.45e+02 ph/cm2/s
90%_error_low -6.91e-01 -6.08e-01 -4.39e-01 -2.02e+00 -1.52e+00 -2.13e+00 ph/cm2/s
90%_error_hi 7.03e-01 6.08e-01 4.38e-01 2.07e+00 1.53e+00 2.15e+00 ph/cm2/s
Fluence CPL 1.02e-05 1.96e-05 2.91e-05 9.25e-05 8.21e-05 1.52e-04 erg/cm2
90%_error_low -3.18e-07 -3.57e-07 -3.46e-07 N/A -9.45e-07 N/A erg/cm2
90%_error_hi 3.24e-07 3.58e-07 3.45e-07 N/A 9.51e-07 N/A erg/cm2
Peak flux CPL 9.17e+00 7.02e+00 3.77e+00 3.56e+00 2.14e+01 2.40e+01 ph/cm2/s
90%_error_low -1.17e+00 -5.62e-01 -1.36e-01 -1.80e-01 -1.46e+00 -1.53e+00 ph/cm2/s
90%_error_hi 6.24e-01 3.52e+00 2.92e-01 1.21e-01 2.22e+00 1.59e+00 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 54.5033 -26.9384 0.0017 14.4036 18.1966 66.6956702 114.973 TRIG_00883832 Foreground time interval of the image: -6.604 2.659 (delta_t = 9.263 [sec]) 3.560 14.061 (delta_t = 10.501 [sec]) Background time interval of the image: -239.440 -6.604 (delta_t = 232.836 [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
Multiple GTIs in the spectrum tstart tstop -6.604000 652.170000 653.560000 703.192000 Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.43068 ( -0.0244971 0.0245852 ) Norm@50keV : 1.20664E-02 ( -0.000157982 0.000157165 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 90.47 using 59 PHA bins. # Reduced chi-squared = 1.587 for 57 degrees of freedom # Null hypothesis probability = 3.154757e-03 Photon flux (15-150 keV) in 708.4 sec: 1.48005 ( -0.02461 0.02476 ) ph/cm2/s Energy fluence (15-150 keV) : 8.2105e-05 ( -9.51232e-07 9.50552e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum tstart tstop -6.604000 652.170000 653.560000 703.192000 Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.42711 ( -0.0220235 0.0278178 ) Epeak [keV] : 1.00000E+04 ( -10000 -10000 ) Norm@50keV : 1.21065E-02 ( -0.000157539 0.000139145 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 91.50 using 59 PHA bins. # Reduced chi-squared = 1.634 for 56 degrees of freedom # Null hypothesis probability = 1.930522e-03 Photon flux (15-150 keV) in 708.4 sec: 1.47945 ( -0.0246 0.02479 ) ph/cm2/s Energy fluence (15-150 keV) : 8.2088e-05 ( -9.45445e-07 9.50347e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.232 sec. to 1.232 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.885755 ( -0.0265964 0.026708 ) Norm@50keV : 0.878827 ( -0.0133008 0.013249 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 33.63 using 59 PHA bins. # Reduced chi-squared = 0.5900 for 57 degrees of freedom # Null hypothesis probability = 9.942009e-01 Photon flux (15-150 keV) in 1 sec: 100.861 ( -1.5241 1.527 ) ph/cm2/s Energy fluence (15-150 keV) : 9.91882e-06 ( -1.39695e-07 1.39837e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.232 sec. to 1.232 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.878389 ( -0.0295797 0.0424388 ) Epeak [keV] : 9995.92 ( -9996.34 -9996.34 ) Norm@50keV : 0.884547 ( -0.0124028 0.0405339 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 33.85 using 59 PHA bins. # Reduced chi-squared = 0.6044 for 56 degrees of freedom # Null hypothesis probability = 9.916435e-01 Photon flux (15-150 keV) in 1 sec: 21.3782 ( -1.4593 2.2153 ) ph/cm2/s Energy fluence (15-150 keV) : 9.92842e-06 ( -1.51096e-07 1.28616e-07 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = N/A sec. Hardness ratio (energy fluence ratio) = N/A
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = N/A S(50-150 keV) = N/A
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 = 2.439798759153241E-01, IMY = -8.020057465775930E-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: -239.440000 -6.604000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.3289 -40.4880 4.0 54.0 164.0 3.6814 2.9 9.9 Vela X-1 92.8125 -16.4756 3.7 35.2 105.3 1.9637 3.1 ------ UNKNOWN 3.7229 -32.9037 2.9 47.0 -53.0 5.3257 4.1 ------ UNKNOWN 7.3335 -78.1408 2.8 44.3 -118.1 5.2819 4.2 ------ UNKNOWN 3.4306 -32.8098 3.9 47.2 -53.1 4.5263 3.3 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -6.604000 2.659000 3.560000 14.060600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 135.5543 -40.5299 7.4 54.2 164.2 5.2202 1.6 1.9 Vela X-1 85.4393 -5.2585 2.9 40.2 85.0 11.2080 4.0 ------ UNKNOWN 54.5033 -26.9384 0.1 14.4 18.2 66.6937 115.2 ------ UNKNOWN 129.0287 -53.0027 2.1 46.0 177.8 6.9877 5.5 ------ UNKNOWN 147.6879 -51.9368 1.8 57.1 -179.1 22.6655 6.6 ------ UNKNOWN 7.9026 -11.6390 2.3 55.5 -27.5 12.8409 5.0 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 53.060600 625.660600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 68.1653 -9.3952 2.6 21.8 71.6 2.9120 4.5 ------ UNKNOWN 39.1245 12.2651 2.8 41.9 9.8 3.6151 4.0 ------ UNKNOWN 54.5056 -26.9383 0.2 0.0 -125.0 33.3329 60.8 ------ UNKNOWN 29.3870 11.3239 3.0 45.4 -3.2 3.8987 3.8 ------ UNKNOWN