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 -33.480 sec. to 80.500 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.83693 ( -0.167143 0.161889 )
Norm@50keV : 2.35904E-03 ( -0.000229912 0.000225649 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.99 using 59 PHA bins.
# Reduced chi-squared = 1.193 for 57 degrees of freedom
# Null hypothesis probability = 1.511706e-01
Photon flux (15-150 keV) in 114 sec: 0.329860 ( -0.028835 0.028921 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.47369e-06 ( -2.40706e-07 2.43409e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -33.480 sec. to 80.500 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.84265 ( -0.985398 0.428289 )
Epeak [keV] : 9999.34 ( -9999.35 -9999.36 )
Norm@50keV : 2.35218E-03 ( -0.00156766 0.00150036 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.00 using 59 PHA bins.
# Reduced chi-squared = 1.214 for 56 degrees of freedom
# Null hypothesis probability = 1.305602e-01
Photon flux (15-150 keV) in 114 sec: 0.296752 ( -0.055354 0.049549 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.31337e-06 ( -4.66802e-07 1.18415e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 69.904 sec. to 70.904 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.70745 ( -0.685827 0.615317 )
Norm@50keV : 5.47449E-03 ( -0.00237915 0.00230706 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.98 using 59 PHA bins.
# Reduced chi-squared = 1.175 for 57 degrees of freedom
# Null hypothesis probability = 1.719174e-01
Photon flux (15-150 keV) in 1 sec: 0.728954 ( -0.291018 0.292166 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.06781e-08 ( -2.19061e-08 2.2841e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 69.904 sec. to 70.904 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.0299319 ( -2.20737 5.81197 )
Epeak [keV] : 52.7900 ( )
Norm@50keV : 4.87510E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.71 using 59 PHA bins.
# Reduced chi-squared = 1.173 for 56 degrees of freedom
# Null hypothesis probability = 1.757032e-01
Photon flux (15-150 keV) in 1 sec: 0.700501 ( -0.289545 0.294658 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.55816e-08 ( -2.11518e-08 2.43639e-08 ) ergs/cm2
Time-resolved spectra
