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 -15.204 sec. to 134.984 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.20592 ( -0.0790486 0.0800151 )
Norm@50keV : 3.93259E-03 ( -0.00017143 0.000170644 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.58 using 59 PHA bins.
# Reduced chi-squared = 0.7997 for 57 degrees of freedom
# Null hypothesis probability = 8.614815e-01
Photon flux (15-150 keV) in 150.2 sec: 0.461996 ( -0.021877 0.021956 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.98329e-06 ( -2.6245e-07 2.62823e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.204 sec. to 134.984 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.20131 ( -0.129647 0.135364 )
Epeak [keV] : 9999.13 ( -9999.14 -9999.14 )
Norm@50keV : 3.95113E-03 ( -0.000169041 0.00057633 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.66 using 59 PHA bins.
# Reduced chi-squared = 0.8153 for 56 degrees of freedom
# Null hypothesis probability = 8.367020e-01
Photon flux (15-150 keV) in 150.2 sec: 0.461874 ( -0.021874 0.02196 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.00026e-06 ( -2.80872e-07 2.44125e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.756 sec. to 1.756 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11344 ( -0.228855 0.233506 )
Norm@50keV : 1.77232E-02 ( -0.00227774 0.00226682 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.52 using 59 PHA bins.
# Reduced chi-squared = 1.079 for 57 degrees of freedom
# Null hypothesis probability = 3.175392e-01
Photon flux (15-150 keV) in 1 sec: 2.05853 ( -0.27572 0.27756 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.84531e-07 ( -2.49468e-08 2.50394e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.756 sec. to 1.756 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.78182 ( -0.337931 0.976825 )
Epeak [keV] : 231.437 ( -541.506 -541.506 )
Norm@50keV : 1.39790E-03 ( -0.00140045 0.00314368 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.65 using 59 PHA bins.
# Reduced chi-squared = 1.047 for 56 degrees of freedom
# Null hypothesis probability = 3.785306e-01
Photon flux (15-150 keV) in 1 sec: 2.04646 ( -0.29113 0.28517 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.84043e-07 ( -2.53528e-08 2.52863e-08 ) ergs/cm2
Time-resolved spectra
