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 0.212 sec. to 0.952 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.314011 ( -0.249946 0.277123 )
Norm@50keV : 3.96473E-02 ( -0.00625401 0.0059235 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.55 using 59 PHA bins.
# Reduced chi-squared = 0.9922 for 57 degrees of freedom
# Null hypothesis probability = 4.917746e-01
Photon flux (15-150 keV) in 0.74 sec: 4.87466 ( -0.59017 0.59267 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.35133e-07 ( -5.34242e-08 5.35892e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.212 sec. to 0.952 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.301693 ( -0.359591 0.693465 )
Epeak [keV] : 9999.24 ( -9999.29 -9999.29 )
Norm@50keV : 4.00150E-02 ( -0.00586857 0.0276726 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.58 using 59 PHA bins.
# Reduced chi-squared = 1.010 for 56 degrees of freedom
# Null hypothesis probability = 4.531118e-01
Photon flux (15-150 keV) in 0.74 sec: 4.87243 ( -0.58997 0.59238 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.35785e-07 ( -7.03061e-08 6.90763e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.082 sec. to 1.082 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.414109 ( -0.242556 0.267046 )
Norm@50keV : 3.31416E-02 ( -0.00499291 0.00478189 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.02 using 59 PHA bins.
# Reduced chi-squared = 1.035 for 57 degrees of freedom
# Null hypothesis probability = 4.016008e-01
Photon flux (15-150 keV) in 1 sec: 3.98655 ( -0.49481 0.49756 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.65575e-07 ( -5.94965e-08 5.98128e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.082 sec. to 1.082 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.403377 ( -0.268982 0.264514 )
Epeak [keV] : 9999.99 ( -9999.99 -9999.99 )
Norm@50keV : 3.34446E-02 ( -0.00501929 0.00398133 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.02 using 59 PHA bins.
# Reduced chi-squared = 1.054 for 56 degrees of freedom
# Null hypothesis probability = 3.658732e-01
Photon flux (15-150 keV) in 1 sec: 3.98169 ( -0.51816 0.50085 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.89756e-07 ( -9.07311e-08 4.02246e-08 ) ergs/cm2
Time-resolved spectra
