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 -1.532 sec. to 58.376 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.21834 ( -0.234745 0.241159 )
Norm@50keV : 1.23973E-03 ( -0.000167895 0.000167811 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.61 using 59 PHA bins.
# Reduced chi-squared = 0.6247 for 57 degrees of freedom
# Null hypothesis probability = 9.882331e-01
Photon flux (15-150 keV) in 59.91 sec: 0.145907 ( -0.020546 0.020622 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.49756e-07 ( -1.10361e-07 1.11316e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.532 sec. to 58.376 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.888843 ( -0.534714 1.09111 )
Epeak [keV] : 179.998 ( -180.008 -180.008 )
Norm@50keV : 1.78330E-03 ( -0.000690971 0.00393894 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.23 using 59 PHA bins.
# Reduced chi-squared = 0.6291 for 56 degrees of freedom
# Null hypothesis probability = 9.864954e-01
Photon flux (15-150 keV) in 59.91 sec: 0.143876 ( -0.021358 0.021345 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.33586e-07 ( -1.22068e-07 1.19414e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 30.600 sec. to 31.600 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11132 ( -0.561638 0.604743 )
Norm@50keV : 4.05151E-03 ( -0.00128365 0.00126821 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.03 using 59 PHA bins.
# Reduced chi-squared = 1.123 for 57 degrees of freedom
# Null hypothesis probability = 2.435193e-01
Photon flux (15-150 keV) in 1 sec: 0.470476 ( -0.152803 0.154573 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.22124e-08 ( -1.40188e-08 1.42267e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 30.600 sec. to 31.600 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.794811 ( 0.794797 3.03108 )
Epeak [keV] : 224.527 ( -224.519 -224.519 )
Norm@50keV : 5.55475E-03 ( -0.00269529 0.0778375 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.96 using 59 PHA bins.
# Reduced chi-squared = 1.142 for 56 degrees of freedom
# Null hypothesis probability = 2.172477e-01
Photon flux (15-150 keV) in 1 sec: 0.463216 ( -0.160221 0.155548 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.1686e-08 ( -1.46638e-08 1.43904e-08 ) ergs/cm2
Time-resolved spectra
