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 26.492 sec. to 70.252 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67581 ( -0.222503 0.216082 )
Norm@50keV : 1.86171E-03 ( -0.000246289 0.000240831 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.15 using 59 PHA bins.
# Reduced chi-squared = 0.6693 for 57 degrees of freedom
# Null hypothesis probability = 9.741041e-01
Photon flux (15-150 keV) in 43.76 sec: 0.245212 ( -0.028803 0.028822 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.55941e-07 ( -1.05126e-07 1.07032e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 26.492 sec. to 70.252 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.17498 ( -0.219217 0.221928 )
Epeak [keV] : 67.1008 ( -9999.35 -9999.36 )
Norm@50keV : 9.99663E-04 ( -0.000257501 0.00206501 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.14 using 59 PHA bins.
# Reduced chi-squared = 0.6632 for 56 degrees of freedom
# Null hypothesis probability = 9.755061e-01
Photon flux (15-150 keV) in 43.76 sec: 0.246240 ( -0.033371 0.031542 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.67835e-07 ( -1.00141e-07 9.48205e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 30.752 sec. to 31.752 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.45062 ( -0.628233 0.660115 )
Norm@50keV : 4.68021E-03 ( -0.00153661 0.001473 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.02 using 59 PHA bins.
# Reduced chi-squared = 0.7898 for 57 degrees of freedom
# Null hypothesis probability = 8.746242e-01
Photon flux (15-150 keV) in 1 sec: 0.576869 ( -0.180961 0.181271 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.47878e-08 ( -1.58684e-08 1.64571e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 30.752 sec. to 31.752 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.32047 ( -0.0869349 1.89113 )
Epeak [keV] : 112.899 ( )
Norm@50keV : 1.61519E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.69 using 59 PHA bins.
# Reduced chi-squared = 0.7981 for 56 degrees of freedom
# Null hypothesis probability = 8.612568e-01
Photon flux (15-150 keV) in 1 sec: 0.362052 ( -0.362052 0.239345 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.45872e-08 ( -1.58953e-08 1.612e-08 ) ergs/cm2
Time-resolved spectra
