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: Sun Mar 17 22:59:35 EDT 2019
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger882252
======================================================================
Trigger: 00882252 Segment: 000
BAT Trigger Time: 568474506.816 [s; MET]
Trigger Stop: 568474507.328 [s; MET]
UTC: 2019-01-06T13:34:44.611040 [includes UTCF correction]
Where From?: TDRSS position message
BAT
RA: 29.8861170639664 Dec: 23.8568699774236 [deg; J2000]
Catalogged Source?: NO
Point Source?: YES
GRB Indicated?: YES [ by BAT flight software ]
Image S/N Ratio: 8.34
Image Trigger?: NO
Rate S/N Ratio: 16.2172747402269 [ if not an image trigger ]
Image S/N Ratio: 8.34
Analysis Position: [ source = BAT ]
RA: 29.8861170639664 Dec: 23.8568699774236 [deg; J2000]
Refined Position: [ source = BAT pre-slew burst ]
RA: 29.8783469872996 Dec: 23.8395668658353 [deg; J2000]
{ 01h 59m 30.8s , +23d 50' 22.4" }
+/- 0.807463733533503 [arcmin] (estimated 90% radius based on SNR)
+/- 0.27309884411791 [arcmin] (formal 1-sigma fit error)
SNR: 41.2857113732231
Angular difference between the analysis and refined position is 1.122341 arcmin
Partial Coding Fraction: 0.65625 [ including projection effects ]
Duration
T90: 78.095999956131 +/- 2.08513594337612
Measured from: 1.85600006580353
to: 79.9520000219345 [s; relative to TRIGTIME]
T50: 62.0879999399185 +/- 0.639362154458515
Measured from: 10.9639999866486
to: 73.0519999265671 [s; relative to TRIGTIME]
Fluence
Peak Flux (peak 1 second)
Measured from: 75.2760000228882
to: 76.2760000228882 [s; relative to TRIGTIME]
Total Fluence
Measured from: -0.123999953269958
to: 96.6160000562668 [s; relative to TRIGTIME]
Band 1 Band 2 Band 3 Band 4
15-25 25-50 50-100 100-350 keV
Total 2.779173 3.554286 2.628089 0.602124
0.071938 0.075414 0.065843 0.055096 [error]
Peak 0.166576 0.252362 0.158662 0.025274
0.008892 0.009950 0.008639 0.005872 [error]
[ fluence units of on-axis counts / fully illuminated detector ]
======================================================================
====== Table of the duration information =============================
Value tstart tstop
T100 96.740 -0.124 96.616
T90 78.096 1.856 79.952
T50 62.088 10.964 73.052
Peak 1.000 75.276 76.276
====== 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 -1.588 -0.052 0.052 - - - 6.47e-03 -1.74e-04 1.74e-04 41.200 57
CPL -1.368 -0.201 0.210 154.628 -50.066 738.297 8.19e-03 -1.54e-03 2.00e-03 37.680 56
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: CPL)
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 -1.605 -0.082 0.081 - - - 3.79e-02 -1.92e-03 1.91e-03 72.560 57
CPL -0.893 -0.356 0.389 74.771 -11.898 28.201 8.92e-02 -3.05e-02 5.24e-02 59.880 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 8.69e-07 1.51e-06 2.01e-06 5.47e-06 5.86e-06 9.86e-06 erg/cm2
90%_error_low -4.57e-08 -4.60e-08 -6.90e-08 -4.17e-07 -1.66e-07 -4.57e-07 erg/cm2
90%_error_hi 4.67e-08 4.59e-08 6.88e-08 4.40e-07 1.66e-07 4.75e-07 erg/cm2
Peak flux PL 1.73e+00 1.63e+00 1.07e+00 1.09e+00 4.88e+00 5.53e+00 ph/cm2/s
90%_error_low -1.36e-01 -8.25e-02 -6.83e-02 -1.33e-01 -2.40e-01 -2.69e-01 ph/cm2/s
90%_error_hi 1.39e-01 8.23e-02 6.81e-02 1.43e-01 2.40e-01 2.69e-01 ph/cm2/s
Fluence CPL 8.57e-07 1.16e-06 1.21e-06 2.84e-06 4.00e-06 6.07e-06 erg/cm2
90%_error_low -4.17e-08 -8.01e-08 -6.62e-08 -1.74e-07 -2.40e-07 -2.12e-07 erg/cm2
90%_error_hi 4.16e-08 7.34e-08 5.71e-08 1.61e-07 2.09e-07 1.84e-07 erg/cm2
Peak flux CPL 1.54e+00 1.75e+00 1.12e+00 5.09e-01 4.74e+00 4.93e+00 ph/cm2/s
90%_error_low -1.61e-01 -1.03e-01 -7.69e-02 -1.56e-01 -2.49e-01 -2.99e-01 ph/cm2/s
90%_error_hi 1.63e-01 1.05e-01 7.75e-02 2.24e-01 2.49e-01 3.25e-01 ph/cm2/s
======================================================================
Image
Pre-slew 15.0-350.0 keV image (Event data)
# RAcent DECcent POSerr Theta Phi Peak Cts SNR Name 29.8783 23.8396 0.0047 33.5753 -149.6076 2.7932499 41.286 TRIG_00882252 Foreground time interval of the image: -0.124 11.885 (delta_t = 12.009 [sec]) Background time interval of the image: -572.715 -554.030 (delta_t = 18.686 [sec]) -239.816 -0.124 (delta_t = 239.692 [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 -0.124 sec. to 96.616 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.58844 ( -0.0517753 0.0516712 ) Norm@50keV : 6.47202E-03 ( -0.000173924 0.000173877 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 41.20 using 59 PHA bins. # Reduced chi-squared = 0.7229 for 57 degrees of freedom # Null hypothesis probability = 9.429108e-01 Photon flux (15-150 keV) in 96.74 sec: 0.828762 ( -0.024651 0.024735 ) ph/cm2/s Energy fluence (15-150 keV) : 5.86457e-06 ( -1.65606e-07 1.65966e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.124 sec. to 96.616 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.36822 ( -0.200549 0.210106 ) Epeak [keV] : 154.628 ( -50.0653 738.298 ) Norm@50keV : 8.18970E-03 ( -0.00154095 0.00200013 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 37.68 using 59 PHA bins. # Reduced chi-squared = 0.6728 for 56 degrees of freedom # Null hypothesis probability = 9.714335e-01 Photon flux (15-150 keV) in 96.74 sec: 0.814324 ( -0.027627 0.027746 ) ph/cm2/s Energy fluence (15-150 keV) : 4.00365e-06 ( -2.40116e-07 2.08519e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 75.276 sec. to 76.276 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.60516 ( -0.0820543 0.0812595 ) Norm@50keV : 3.79181E-02 ( -0.00191809 0.00191124 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 72.56 using 59 PHA bins. # Reduced chi-squared = 1.273 for 57 degrees of freedom # Null hypothesis probability = 8.025763e-02 Photon flux (15-150 keV) in 1 sec: 4.88064 ( -0.24029 0.24046 ) ph/cm2/s Energy fluence (15-150 keV) : 3.54446e-07 ( -1.91642e-08 1.92513e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 75.276 sec. to 76.276 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.892926 ( -0.35556 0.389094 ) Epeak [keV] : 74.7712 ( -11.8985 28.2012 ) Norm@50keV : 8.92257E-02 ( -0.0304938 0.0523995 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 59.88 using 59 PHA bins. # Reduced chi-squared = 1.069 for 56 degrees of freedom # Null hypothesis probability = 3.369476e-01 Photon flux (15-150 keV) in 1 sec: 4.74436 ( -0.24939 0.24935 ) ph/cm2/s Energy fluence (15-150 keV) : 3.35885e-07 ( -2.13782e-08 2.14043e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 78.096 sec. Hardness ratio (energy fluence ratio) = 1.33014737193
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 2.3810565e-06 S(50-150 keV) = 3.483593e-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 = -5.725623150005047E-01, IMY = 3.358176116065797E-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: -572.715410 -554.029900 -239.816000 -0.124000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.6476 22.0126 0.7 33.2 111.9 9.3900 15.6 0.8 Crab 40.8992 61.4309 0.6 16.3 -53.9 5.8787 19.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image: -0.124000 11.884600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.5102 21.9351 7.4 33.2 112.1 -0.1738 -1.6 8.3 Crab 90.6392 18.2681 3.1 39.8 105.8 0.7299 3.7 ------ UNKNOWN 29.8783 23.8396 0.3 33.6 -149.6 2.7932 41.3 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image: 70.484590 901.984600 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 72.2663 44.2358 4.1 40.0 65.5 6.5769 2.8 ------ UNKNOWN 40.9248 61.4357 0.7 38.3 25.2 17.4535 16.2 ------ UNKNOWN 16.4508 59.1153 3.1 36.5 5.2 3.1101 3.7 ------ UNKNOWN 16.4341 19.9694 2.2 13.1 -88.0 3.3134 5.2 ------ UNKNOWN 2.6690 27.6441 2.8 24.7 -58.7 2.9084 4.0 ------ UNKNOWN 8.1009 -22.5756 3.4 51.0 -137.1 12.8108 3.4 ------ UNKNOWN