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 Ver: batgrbproduct v2.46
Process Start Time: Mon Apr 13 01:27:59 EDT 2015
Host Name: bat1
Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
======================================================================
Trigger: 00548918 Segment: 000
BAT Trigger Time: 382733900.8
UTC: 2013-02-16T18:58:10.575 [includes UTCF correction]
Where From?: Ground analysis (best_duration.txt)
NOTE: BAT trigger time for ground-detected burst is the T100 start time.
Analysis Position: [ source = GCN ]
RA: 58.866 Dec: 2.036 [deg; J2000]
Refined Position: [ source = BAT pre-slew image ]
RA: 58.866 Dec: 2.03603 [deg; J2000]
{ 03h 55m 27.8s , +02d 02' 09.7" }
+/- 1.41968723301 [arcmin] (estimated 90% radius based on SNR)
SNR: 18.4398374315
Angular difference between the analysis and refined position is 0.001800 arcmin
Partial Coding Fraction: 0.078125 [ including projection effects ]
Duration
T90: 17.6000000238419 +/- 1.6
Measured from: 0
to: 17.6 [s; relative to TRIGTIME]
T50: 9.60000002384186 +/- 1.6
Measured from: 3.2
to: 12.8 [s; relative to TRIGTIME]
====== Table of the duration information =============================
Value tstart tstop
T100 17.600 0.000 17.600
T90 17.600 0.000 17.600
T50 9.600 3.200 12.800
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 -1.987 -0.145 0.140 - - - 2.33e-02 -2.05e-03 2.02e-03 68.990 57
CPL -1.530 -0.549 0.627 50.166 N/A N/A 4.00e-02 N/A N/A 67.010 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 -2.070 -0.246 0.229 - - - 4.35e-02 -7.07e-03 6.90e-03 73.920 57
CPL -1.191 -0.937 1.367 41.851 N/A N/A 1.33e-01 N/A N/A 71.970 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 4.70e-07 6.43e-07 6.49e-07 1.19e-06 2.15e-06 2.95e-06 erg/cm2
90%_error_low -5.73e-08 -5.09e-08 -7.66e-08 -2.64e-07 -1.81e-07 -3.45e-07 erg/cm2
90%_error_hi 5.94e-08 5.09e-08 7.63e-08 3.07e-07 1.82e-07 3.73e-07 erg/cm2
Peak flux PL 3.10e+00 2.23e+00 1.06e+00 7.15e-01 6.74e+00 7.12e+00 ph/cm2/s
90%_error_low -6.28e-01 -3.18e-01 -2.18e-01 -2.45e-01 -9.83e-01 -1.01e+00 ph/cm2/s
90%_error_hi 6.57e-01 3.17e-01 2.16e-01 3.01e-01 9.85e-01 1.01e+00 ph/cm2/s
Fluence CPL N/A N/A N/A N/A N/A N/A erg/cm2
90%_error_low -5.73e-08 -5.09e-08 -7.66e-08 -2.64e-07 -1.81e-07 -3.45e-07 erg/cm2
90%_error_hi 5.94e-08 5.09e-08 7.63e-08 3.07e-07 1.82e-07 3.73e-07 erg/cm2
Peak flux CPL 2.79e+00 2.48e+00 1.12e+00 2.94e-01 6.61e+00 6.68e+00 ph/cm2/s
90%_error_low -7.39e-01 -4.34e-01 -2.54e-01 -2.12e-01 -1.00e+00 -1.04e+00 ph/cm2/s
90%_error_hi 7.57e-01 4.59e-01 2.55e-01 6.00e-01 1.00e+00 1.08e+00 ph/cm2/s
======================================================================
Image
15.0-350.0 keV image (Event data)
#RAcent DECcent POSerr Theta Phi Peak_Cts SNR Name 58.866 2.036 0.000 54.320 173.812 3.660 18.440 TRIG_00548918 Image time interval: 0.200 to 10.208 [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 0.200 sec. to 10.208 sec. Spectral model in power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.98679 ( -0.145303 0.14014 ) Norm@50keV : 2.32526E-02 ( -0.00204835 0.0020214 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 68.99 using 59 PHA bins. # Reduced chi-squared = 1.210 for 57 degrees of freedom # Null hypothesis probability = 1.326453e-01 Photon flux (15-150 keV) in 10.01 sec: 3.46711 ( -0.28629 0.28718 ) ph/cm2/s Energy fluence (15-150 keV) : 2.14543e-06 ( -1.8106e-07 1.82144e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.200 sec. to 10.208 sec. Spectral model in the cutoff power-law: ------------------------------------------------------------ Parameters : value lower 90% higher 90% Photon index: -1.5302 ( -0.549428 0.62661 ) Epeak [keV] : 50.1660 ( ) Norm@50keV : 4.00374E-02 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 67.01 using 59 PHA bins. # Reduced chi-squared = 1.197 for 56 degrees of freedom # Null hypothesis probability = 1.488922e-01 Photon flux (15-150 keV) in 10.01 sec: 3.38941 ( -0.30097 0.30177 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) 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: -2.07004 ( -0.245677 0.229418 ) Norm@50keV : 4.34855E-02 ( -0.00706517 0.00689954 ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 73.92 using 59 PHA bins. # Reduced chi-squared = 1.297 for 57 degrees of freedom # Null hypothesis probability = 6.527721e-02 Photon flux (15-150 keV) in 1 sec: 6.74251 ( -0.98286 0.98506 ) ph/cm2/s Energy fluence (15-150 keV) : 4.03014e-07 ( -6.10267e-08 6.13409e-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: -1.19108 ( -0.937292 1.36686 ) Epeak [keV] : 41.8512 ( ) Norm@50keV : 0.132541 ( ) ------------------------------------------------------------ #Fit statistic : Chi-Squared = 71.97 using 59 PHA bins. # Reduced chi-squared = 1.285 for 56 degrees of freedom # Null hypothesis probability = 7.388614e-02 Photon flux (15-150 keV) in 1 sec: 6.60883 ( -0.99961 1.00052 ) ph/cm2/s Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
Distribution
T90 vs. Hardness ratio plot
T90 = 17.6 sec. Hardness ratio (energy fluence ratio) = 1.00925290315
S(15-50 keV) vs. S(50-150 keV) plot
S(15-50 keV) = 1.1136648e-06 S(50-150 keV) = 1.0317996e-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 = -1.3845475793, IMY = -0.150111531791
Spacecraft aspect plot
Bright source in the event data image
Event data image of 15-350 keV band
Time interval of the image: 2.008000 4.728000 # RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name # [deg] [deg] ['] [deg] [deg] ['] 83.5917 21.8871 4.9 44.8 134.3 0.2887 2.4 8.0 Crab 149.0325 68.5439 2.0 45.6 43.4 0.5678 5.9 ------ UNKNOWN 77.4746 82.0254 2.0 29.1 23.3 0.2025 5.9 ------ UNKNOWN
Webpage updated on: Tue Nov 24 23:40:18 EST 2015