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 -14.540 sec. to 49.732 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.32799 ( -0.0365993 0.036685 )
Norm@50keV : 1.30047E-02 ( -0.000253416 0.000253279 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.69 using 59 PHA bins.
# Reduced chi-squared = 0.7841 for 57 degrees of freedom
# Null hypothesis probability = 8.818563e-01
Photon flux (15-150 keV) in 64.27 sec: 1.55979 ( -0.03403 0.03413 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.20535e-06 ( -1.63643e-07 1.6374e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -14.540 sec. to 49.732 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10835 ( -0.147153 0.152038 )
Epeak [keV] : 237.680 ( -72.8928 332.071 )
Norm@50keV : 1.61597E-02 ( -0.00213879 0.00254565 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.13 using 59 PHA bins.
# Reduced chi-squared = 0.6809 for 56 degrees of freedom
# Null hypothesis probability = 9.675692e-01
Photon flux (15-150 keV) in 64.27 sec: 1.53391 ( -0.03767 0.03785 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.31191e-06 ( -2.31998e-07 1.9616e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 30.484 sec. to 31.484 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.994289 ( -0.0651752 0.0656374 )
Norm@50keV : 5.71265E-02 ( -0.00220235 0.00220021 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 76.88 using 59 PHA bins.
# Reduced chi-squared = 1.349 for 57 degrees of freedom
# Null hypothesis probability = 4.076938e-02
Photon flux (15-150 keV) in 1 sec: 0.399891 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 6.19056e-07 ( -2.57756e-08 2.58256e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 30.484 sec. to 31.484 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.528335 ( -0.263866 0.279998 )
Epeak [keV] : 184.342 ( -47.8206 155.298 )
Norm@50keV : 9.16130E-02 ( -0.0209739 0.0288954 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.39 using 59 PHA bins.
# Reduced chi-squared = 1.203 for 56 degrees of freedom
# Null hypothesis probability = 1.416438e-01
Photon flux (15-150 keV) in 1 sec: 6.46699 ( -0.26396 0.26417 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.71064e-08 ( -2.16036e-08 1.8022e-08 ) ergs/cm2
Time-resolved spectra
