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 110.328 sec. to 663.040 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.74961 ( -0.142547 0.139524 )
Norm@50keV : 8.47370E-04 ( -7.39574e-05 7.30378e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.05 using 59 PHA bins.
# Reduced chi-squared = 1.124 for 57 degrees of freedom
# Null hypothesis probability = 2.429419e-01
Photon flux (15-150 keV) in 552.7 sec: 0.114568 ( -0.008934 0.008939 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.32235e-06 ( -3.88934e-07 3.94041e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 110.328 sec. to 663.040 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.42906 ( -0.476461 0.635563 )
Epeak [keV] : 79.0396 ( -30.999 -79.0398 )
Norm@50keV : 1.27625E-03 ( -0.000487166 0.00158505 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.08 using 59 PHA bins.
# Reduced chi-squared = 1.126 for 56 degrees of freedom
# Null hypothesis probability = 2.403247e-01
Photon flux (15-150 keV) in 552.7 sec: 0.112944 ( -0.009386 0.009355 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.1733e-06 ( -4.65814e-07 4.66396e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 230.144 sec. to 231.144 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.8462 ( -0.609175 0.500962 )
Norm@50keV : 6.27911E-03 ( -0.00236307 0.00218631 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.79 using 59 PHA bins.
# Reduced chi-squared = 1.102 for 57 degrees of freedom
# Null hypothesis probability = 2.785910e-01
Photon flux (15-150 keV) in 1 sec: 0.881284 ( -0.252997 0.252996 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.77471e-08 ( -2.03576e-08 2.13936e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 230.144 sec. to 231.144 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.04044 ( -1.15866 3.60296 )
Epeak [keV] : 56.5770 ( )
Norm@50keV : 1.68536E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.39 using 59 PHA bins.
# Reduced chi-squared = 1.114 for 56 degrees of freedom
# Null hypothesis probability = 2.594371e-01
Photon flux (15-150 keV) in 1 sec: 0.861996 ( -0.262789 0.258534 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.52764e-08 ( -1.83497e-08 1.57566e-08 ) ergs/cm2
Time-resolved spectra
