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 -15.032 sec. to 48.968 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.96834 ( -0.384601 0.340247 )
Norm@50keV : 8.79065E-04 ( -0.000212885 0.000201839 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.44 using 59 PHA bins.
# Reduced chi-squared = 0.6744 for 57 degrees of freedom
# Null hypothesis probability = 9.718691e-01
Photon flux (15-150 keV) in 64 sec: 0.129986 ( -0.024153 0.024162 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.18167e-07 ( -1.15506e-07 1.18834e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.032 sec. to 48.968 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.65099 ( -0.530835 1.40069 )
Epeak [keV] : 51.2900 ( -49.9107 -51.2237 )
Norm@50keV : 1.30418E-03 ( -0.00130738 0.00590022 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.22 using 59 PHA bins.
# Reduced chi-squared = 0.6826 for 56 degrees of freedom
# Null hypothesis probability = 9.667414e-01
Photon flux (15-150 keV) in 64 sec: 0.128566 ( -0.024686 0.024664 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.08335e-07 ( -1.18366e-07 1.29253e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 40.468 sec. to 41.468 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.09404 ( -0.822778 1.01655 )
Norm@50keV : 3.26414E-03 ( -0.00156786 0.00144146 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.28 using 59 PHA bins.
# Reduced chi-squared = 0.8821 for 57 degrees of freedom
# Null hypothesis probability = 7.233181e-01
Photon flux (15-150 keV) in 1 sec: 0.378401 ( -0.175725 0.178959 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.41964e-08 ( -1.54947e-08 1.56886e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 40.468 sec. to 41.468 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.08871 ( -0.827023 1.02531 )
Epeak [keV] : 9999.34 ( -9999.36 -9999.36 )
Norm@50keV : 3.28145E-03 ( -0.00156795 0.0904732 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.28 using 59 PHA bins.
# Reduced chi-squared = 0.8979 for 56 degrees of freedom
# Null hypothesis probability = 6.901041e-01
Photon flux (15-150 keV) in 1 sec: 0.381879 ( -0.381879 0.182649 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.43416e-08 ( -1.64442e-08 1.26035e-08 ) ergs/cm2
Time-resolved spectra
