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 -0.036 sec. to 9.312 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.52836 ( -0.222498 0.219949 )
Norm@50keV : 3.11909E-03 ( -0.00040331 0.000398262 )
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#Fit statistic : Chi-Squared = 62.83 using 59 PHA bins.
# Reduced chi-squared = 1.102 for 57 degrees of freedom
# Null hypothesis probability = 2.773965e-01
Photon flux (15-150 keV) in 9.348 sec: 0.392441 ( -0.04844 0.048497 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.75403e-07 ( -3.89101e-08 3.94866e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.036 sec. to 9.312 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.52962 ( -0.220702 0.22448 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 3.12120E-03 ( -0.00225277 0.00435825 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.84 using 59 PHA bins.
# Reduced chi-squared = 1.122 for 56 degrees of freedom
# Null hypothesis probability = 2.470212e-01
Photon flux (15-150 keV) in 9.348 sec: 0.393417 ( -0.051805 0.049339 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.77958e-07 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.120 sec. to 2.120 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.50511 ( -0.325436 0.327818 )
Norm@50keV : 7.26617E-03 ( -0.00128593 0.00125803 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.97 using 59 PHA bins.
# Reduced chi-squared = 1.210 for 57 degrees of freedom
# Null hypothesis probability = 1.329721e-01
Photon flux (15-150 keV) in 1 sec: 0.908380 ( -0.153933 0.15404 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.88811e-08 ( -1.34006e-08 1.36428e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.120 sec. to 2.120 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.50428 ( -0.303865 0.45031 )
Epeak [keV] : 1.00000E+04 ( -10000 -10000 )
Norm@50keV : 7.28521E-03 ( -0.00129489 -0.00728523 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.99 using 59 PHA bins.
# Reduced chi-squared = 1.232 for 56 degrees of freedom
# Null hypothesis probability = 1.140564e-01
Photon flux (15-150 keV) in 1 sec: 0.918153 ( -0.159414 0.146057 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.83469e-08 ( -1.50172e-08 1.13856e-08 ) ergs/cm2
Time-resolved spectra
