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 -2.736 sec. to 70.700 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.58832 ( -0.0787919 0.0787535 )
Norm@50keV : 5.17769E-03 ( -0.000214594 0.000214501 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.60 using 59 PHA bins.
# Reduced chi-squared = 1.116 for 57 degrees of freedom
# Null hypothesis probability = 2.553776e-01
Photon flux (15-150 keV) in 73.44 sec: 0.662994 ( -0.030646 0.030778 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.56174e-06 ( -1.54035e-07 1.544e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.736 sec. to 70.700 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.58558 ( -0.0797529 0.146019 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 5.19054E-03 ( -0.000215071 0.000981749 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.63 using 59 PHA bins.
# Reduced chi-squared = 1.136 for 56 degrees of freedom
# Null hypothesis probability = 2.258059e-01
Photon flux (15-150 keV) in 73.44 sec: 0.662907 ( -0.030653 0.030782 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.57431e-06 ( -2.22552e-07 2.01783e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 22.028 sec. to 23.028 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.70232 ( -0.267409 0.25856 )
Norm@50keV : 1.21977E-02 ( -0.00187253 0.00184137 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.07 using 59 PHA bins.
# Reduced chi-squared = 0.8433 for 57 degrees of freedom
# Null hypothesis probability = 7.942636e-01
Photon flux (15-150 keV) in 1 sec: 1.62138 ( -0.24323 0.24445 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.12933e-07 ( -1.79338e-08 1.80545e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 22.028 sec. to 23.028 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.70717 ( -0.264282 0.265099 )
Epeak [keV] : 9999.27 ( -9999.35 -9999.36 )
Norm@50keV : 1.21775E-02 ( -0.00187313 0.0152151 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.07 using 59 PHA bins.
# Reduced chi-squared = 0.8585 for 56 degrees of freedom
# Null hypothesis probability = 7.653809e-01
Photon flux (15-150 keV) in 1 sec: 1.62136 ( -0.24373 0.24421 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.26095e-08 ( -2.51066e-08 1.55789e-08 ) ergs/cm2
Time-resolved spectra
