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 -3.736 sec. to 7.668 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.82701 ( -0.174613 0.167631 )
Norm@50keV : 2.73453E-03 ( -0.00031649 0.000311746 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.25 using 59 PHA bins.
# Reduced chi-squared = 1.162 for 57 degrees of freedom
# Null hypothesis probability = 1.879386e-01
Photon flux (15-150 keV) in 11.4 sec: 0.380851 ( -0.036812 0.036819 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.8681e-07 ( -3.32071e-08 3.38793e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.736 sec. to 7.668 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.339121 ( -0.876316 1.10143 )
Epeak [keV] : 46.2201 ( -6.87421 12.8199 )
Norm@50keV : 1.96872E-02 ( -0.0196876 0.0674123 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.66 using 59 PHA bins.
# Reduced chi-squared = 1.012 for 56 degrees of freedom
# Null hypothesis probability = 4.501923e-01
Photon flux (15-150 keV) in 11.4 sec: 0.360904 ( -0.037938 0.038227 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.48219e-07 ( -3.42678e-08 3.78592e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.168 sec. to 1.168 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.66713 ( -0.207387 0.201261 )
Norm@50keV : 7.66239E-03 ( -0.00109494 0.00108163 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.14 using 59 PHA bins.
# Reduced chi-squared = 0.8972 for 57 degrees of freedom
# Null hypothesis probability = 6.934386e-01
Photon flux (15-150 keV) in 1 sec: 1.00627 ( -0.128144 0.12817 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.11656e-08 ( -1.06385e-08 1.08639e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.168 sec. to 1.168 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.22526 ( -1.06015 1.37127 )
Epeak [keV] : 48.8745 ( -7.91197 14.8456 )
Norm@50keV : 9.52014E-02 ( -0.0952072 0.518322 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.21 using 59 PHA bins.
# Reduced chi-squared = 0.7181 for 56 degrees of freedom
# Null hypothesis probability = 9.447822e-01
Photon flux (15-150 keV) in 1 sec: 0.959897 ( -0.127699 0.128653 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.00441e-08 ( -1.01212e-08 1.13644e-08 ) ergs/cm2
Time-resolved spectra
