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 -28.264 sec. to 58.608 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67837 ( -0.174371 0.170711 )
Norm@50keV : 9.79447E-04 ( -0.000105239 0.000103788 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.35 using 59 PHA bins.
# Reduced chi-squared = 1.147 for 57 degrees of freedom
# Null hypothesis probability = 2.092736e-01
Photon flux (15-150 keV) in 86.87 sec: 0.129119 ( -0.012411 0.012417 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.89314e-07 ( -8.92789e-08 9.08625e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -28.264 sec. to 58.608 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.19373 ( -0.599263 0.834816 )
Epeak [keV] : 72.3272 ( -22.3628 -72.3269 )
Norm@50keV : 1.83459E-03 ( -0.000925879 0.00360131 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.92 using 59 PHA bins.
# Reduced chi-squared = 1.141 for 56 degrees of freedom
# Null hypothesis probability = 2.182364e-01
Photon flux (15-150 keV) in 86.87 sec: 0.126322 ( -0.01307 0.013028 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.43961e-07 ( -1.08776e-07 1.10417e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -3.036 sec. to -2.036 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.29316 ( -0.530692 0.54009 )
Norm@50keV : 3.18315E-03 ( -0.00091106 0.000909732 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.89 using 59 PHA bins.
# Reduced chi-squared = 0.6297 for 57 degrees of freedom
# Null hypothesis probability = 9.870544e-01
Photon flux (15-150 keV) in 1 sec: 0.379288 ( -0.11082 0.111607 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.15116e-08 ( -9.99518e-09 1.02686e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.036 sec. to -2.036 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.22789 ( -1.6335 2.50177 )
Epeak [keV] : 613.676 ( -554.475 -554.475 )
Norm@50keV : 3.42090E-03 ( -0.00348142 0.0576729 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 35.88 using 59 PHA bins.
# Reduced chi-squared = 0.6407 for 56 degrees of freedom
# Null hypothesis probability = 9.833224e-01
Photon flux (15-150 keV) in 1 sec: 0.376504 ( -0.116816 0.11217 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.11774e-08 ( -1.09463e-08 1.05191e-08 ) ergs/cm2
Time-resolved spectra
