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: hand-made scripts that follow steps in batgrbproduct
but without using TDRSS info
Process Start Time: Sun Nov 30 02:51:35 EST 2014
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
==========================================================================
BAT Trigger Time: 348250808.0
UTC: 2012-01-14T16:20:00.217 [includes UTCF correction]
Where From?: Ground analysis (best_duration.txt)
NOTE: BAT trigger time for ground-detected burst is the T100 start time.
Refined Position: [ source = BAT pre-slew image ]
RA: 317.929928197 Dec: 57.0286672666 [deg; J2000]
{ 21h 11m 43.2s , +57d 01' 43.2" }
+/- 2.05337081701 [arcmin] (estimated 90% radius based on SNR)
SNR: 10.8841174223
Angular difference between the analysis and refined position is Usage: arcmin
Partial Coding Fraction: 1.425781e-01 [ including projection effects ]
Duration
T90: 48. +/- 1.6
Measured from: 1.6
to: 49.6 [s; relative to TRIGTIME]
T50: 27.2000000476837 +/- 1.6
Measured from: 11.2
to: 38.4 [s; relative to TRIGTIME]
====== Table of the duration information =============================
Value tstart tstop
T100 51.200 0.000 51.200
T90 48.000 1.600 49.600
T50 27.200 11.200 38.400
Peak 1.000 3.500 4.500
====== 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 -1.221 -0.267 0.280 - - - 9.46e-03 -1.55e-03 1.53e-03 33.820 57
CPL -0.923 0.923 1.250 220.511 -220.511 -220.511 1.26e-02 -4.56e-03 2.71e-02 33.590 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 -1.110 -0.646 0.737 - - - 9.83e-03 -4.50e-03 4.36e-03 59.490 57
CPL 4.429 -3.431 -4.429 80.908 -18.074 175.754 6.88e-01 -6.88e-01 5.80e+01 56.200 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 7.54e-08 1.64e-07 2.82e-07 1.12e-06 7.73e-07 1.64e-06 erg/cm2
90%_error_low -2.37e-08 -3.38e-08 -4.73e-08 -3.69e-07 -1.23e-07 -3.98e-07 erg/cm2
90%_error_hi 2.66e-08 3.30e-08 4.67e-08 4.76e-07 1.23e-07 4.81e-07 erg/cm2
Peak flux PL 2.78e-01 3.54e-01 3.28e-01 5.34e-01 1.14e+00 1.49e+00 ph/cm2/s
90%_error_low -2.78e-01 -1.95e-01 -1.38e-01 -3.35e-01 -5.23e-01 -6.23e-01 ph/cm2/s
90%_error_hi 2.87e-01 2.03e-01 1.38e-01 5.39e-01 5.56e-01 6.23e-01 ph/cm2/s
Fluence CPL 6.93e-08 1.67e-07 2.94e-07 8.06e-07 7.69e-07 1.34e-06 erg/cm2
90%_error_low -3.01e-08 -3.53e-08 -5.62e-08 -5.20e-07 -1.25e-07 -5.29e-07 erg/cm2
90%_error_hi 3.13e-08 3.60e-08 6.26e-08 4.29e-07 1.24e-07 4.60e-07 erg/cm2
Peak flux CPL 1.59e-02 2.11e-01 5.27e-01 1.09e-01 8.56e-01 8.64e-01 ph/cm2/s
90%_error_low -1.59e-02 -2.11e-01 -2.28e-01 -1.09e-01 -3.70e-01 -3.78e-01 ph/cm2/s
90%_error_hi 3.16e-01 3.26e-01 2.34e-01 3.92e-01 6.01e-01 6.97e-01 ph/cm2/s
======================================================================
Image
15.0-350.0 keV image (Event data)
#RAcent DECcent POSerr Theta Phi Peak_Cts SNR Name 317.930 57.029 0.018 55.098 -10.911 1.225 10.884 TRIG_00511739 Image time interval: -2.000 to 8.101 [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.
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 8.101 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.2206 ( -0.267352 0.280063 ) Norm@50keV : 9.46166E-03 ( -0.0015514 0.0015323 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 33.82 using 59 PHA bins. # Reduced chi-squared = 0.5934 for 57 degrees of freedom # Null hypothesis probability = 9.937701e-01 Photon flux (15-150 keV) in 8.101 sec: 1.11394 ( -0.196953 0.19953 ) ph/cm2/s Energy fluence (15-150 keV) : 7.73283e-07 ( -1.23021e-07 1.23069e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 8.101 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -0.922559 ( 0.922559 1.24965 ) Epeak [keV] : 220.511 ( -220.511 -220.511 ) Norm@50keV : 1.26481E-02 ( -0.0045558 0.0270677 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 33.59 using 59 PHA bins. # Reduced chi-squared = 0.5998 for 56 degrees of freedom # Null hypothesis probability = 9.923984e-01 Photon flux (15-150 keV) in 8.101 sec: 1.09833 ( -0.203256 0.20583 ) ph/cm2/s Energy fluence (15-150 keV) : 7.69217e-07 ( -1.25035e-07 1.24251e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 3.500 sec. to 4.500 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.11002 ( -0.647907 0.734717 ) Norm@50keV : 9.82839E-03 ( -0.00449511 0.00436607 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 59.49 using 59 PHA bins. # Reduced chi-squared = 1.044 for 57 degrees of freedom # Null hypothesis probability = 3.849194e-01 Photon flux (15-150 keV) in 1 sec: 1.14047 ( -0.522624 0.55581 ) ph/cm2/s Energy fluence (15-150 keV) : 1.02452e-07 ( -4.2732e-08 4.28796e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.500 sec. to 4.500 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: 5.06589 ( -4.22974 -5.22867 ) Epeak [keV] : 79.8218 ( -16.6982 177.13 ) Norm@50keV : 1.06571 ( -1.33569 57.3345 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 56.19 using 59 PHA bins. # Reduced chi-squared = 1.003 for 56 degrees of freedom # Null hypothesis probability = 4.677735e-01 Photon flux (15-150 keV) in 1 sec: 0.856393 ( -0.369516 0.600697 ) ph/cm2/s Energy fluence (15-150 keV) : 9.33082e-08 ( -4.04722e-08 4.57351e-08 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 48.0 sec. Hardness ratio (energy fluence ratio) = 1.71644611557
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 2.3979086e-07 S(50-150 keV) = 5.33488e-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 = 1.40744006143, IMY = 0.271312476419
Spacecraft aspect plot
Bright source in the event data image
Event data image of 15-350 keV band
Time interval of the image: -2.000000 8.100900 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 308.1646 41.0814 5.3 56.4 -31.6 0.4216 2.2 8.1 Cyg X-3 326.2612 38.4420 7.3 42.3 -30.5 -0.0885 -1.6 8.4 Cyg X-2 317.9299 57.0287 1.1 55.1 -10.9 1.2251 10.9 ------ UNKNOWN
Webpage updated on: Sun Jun 21 01:09:17 EDT 2015