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 -35.800 sec. to 346.680 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.73281 ( -0.137867 0.13529 )
Norm@50keV : 1.74126E-03 ( -0.000138895 0.000137522 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 54.38 using 59 bins.
Reduced chi-squared = 0.954035
# Null hypothesis probability of 5.74e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 382.5 sec: 0.233984 ( -0.0177 0.017747 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.15305e-06 ( -5.08339e-07 5.13353e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -35.800 sec. to 346.680 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.55859 ( -0.302475 0.561358 )
Epeak [keV] : 121.539 ( -61.4001 -121.539 )
Norm@50keV : 2.14679E-03 ( -0.000431431 0.0020087 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 54.04 using 59 bins.
Reduced chi-squared = 0.965
# Null hypothesis probability of 5.49e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 382.5 sec: 0.231865 ( -0.018755 0.018719 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.06152e-06 ( -5.75444e-07 5.70897e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 247.708 sec. to 248.708 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.04943 ( -0.755407 0.589952 )
Norm@50keV : 6.44882E-03 ( -0.00303616 0.00284285 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 51.19 using 59 bins.
Reduced chi-squared = 0.89807
# Null hypothesis probability of 6.92e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.990039 ( -0.367097 0.367611 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.96733e-08 ( -2.47705e-08 2.5859e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 247.708 sec. to 248.708 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.618922 ( -1.52789 4.32936 )
Epeak [keV] : 45.7213 ( -44.5775 -45.7537 )
Norm@50keV : 3.74113E-02 ( -0.0371404 4.90489 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 50.20 using 59 bins.
Reduced chi-squared = 0.896429
# Null hypothesis probability of 6.93e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.959504 ( -0.37115 0.372636 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.77511e-08 ( -2.34633e-08 2.56113e-08 ) ergs/cm2
Time-resolved spectra
