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 19.240 sec. to 48.884 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.78946 ( -0.253905 0.239844 )
Norm@50keV : 1.09940E-03 ( -0.000185687 0.000181161 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.64 using 59 PHA bins.
# Reduced chi-squared = 0.8359 for 57 degrees of freedom
# Null hypothesis probability = 8.067659e-01
Photon flux (15-150 keV) in 29.64 sec: 0.150888 ( -0.020647 0.020647 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.00155e-07 ( -5.08519e-08 5.25064e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 19.240 sec. to 48.884 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.73572 ( -1.12083 1.56976 )
Epeak [keV] : 49.0291 ( -12.3014 -49.0288 )
Norm@50keV : 4.54881E-03 ( -0.00454899 0.0343787 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.15 using 59 PHA bins.
# Reduced chi-squared = 0.8062 for 56 degrees of freedom
# Null hypothesis probability = 8.500175e-01
Photon flux (15-150 keV) in 29.64 sec: 0.145235 ( -0.02137 0.021479 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.65937e-07 ( -5.44084e-08 6.27624e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 41.752 sec. to 42.752 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.26065 ( -1.0399 0.741752 )
Norm@50keV : 1.68410E-03 ( -0.00105366 0.00104396 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.35 using 59 PHA bins.
# Reduced chi-squared = 1.076 for 57 degrees of freedom
# Null hypothesis probability = 3.227601e-01
Photon flux (15-150 keV) in 1 sec: 0.288036 ( -0.106652 0.107219 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.5986e-08 ( -7.73227e-09 9.16064e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 41.752 sec. to 42.752 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.31892 ( -0.0212082 2.57545 )
Epeak [keV] : 188.300 ( )
Norm@50keV : 1.54454E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.34 using 59 PHA bins.
# Reduced chi-squared = 1.095 for 56 degrees of freedom
# Null hypothesis probability = 2.904514e-01
Photon flux (15-150 keV) in 1 sec: 0.270916 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.55654e-08 ( 0 0 ) ergs/cm2
Time-resolved spectra
