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 -4.308 sec. to 40.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.87882 ( -0.0834461 0.0825128 )
Norm@50keV : 4.74292E-03 ( -0.000224292 0.00022272 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.40 using 59 PHA bins.
# Reduced chi-squared = 1.024 for 57 degrees of freedom
# Null hypothesis probability = 4.238722e-01
Photon flux (15-150 keV) in 44.48 sec: 0.674661 ( -0.029738 0.0298 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.93975e-06 ( -9.11809e-08 9.16506e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.308 sec. to 40.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.72351 ( -0.31965 0.350416 )
Epeak [keV] : 80.2785 ( -29.0075 -80.2883 )
Norm@50keV : 5.75585E-03 ( -0.001087 0.0030937 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.74 using 59 PHA bins.
# Reduced chi-squared = 1.031 for 56 degrees of freedom
# Null hypothesis probability = 4.106951e-01
Photon flux (15-150 keV) in 44.48 sec: 0.668110 ( -0.032689 0.032648 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.90614e-06 ( -1.14774e-07 1.12201e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 14.400 sec. to 15.400 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.88711 ( -0.219727 0.207228 )
Norm@50keV : 1.11776E-02 ( -0.00161178 0.00157103 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.76 using 59 PHA bins.
# Reduced chi-squared = 1.276 for 57 degrees of freedom
# Null hypothesis probability = 7.791371e-02
Photon flux (15-150 keV) in 1 sec: 1.59549 ( -0.18532 0.18535 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02773e-07 ( -1.44142e-08 1.47168e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 14.400 sec. to 15.400 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.27391 ( -0.801029 0.983939 )
Epeak [keV] : 51.6059 ( )
Norm@50keV : 2.47596E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.17 using 59 PHA bins.
# Reduced chi-squared = 1.271 for 56 degrees of freedom
# Null hypothesis probability = 8.334988e-02
Photon flux (15-150 keV) in 1 sec: 1.56277 ( -0.19029 0.19034 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.73509e-08 ( -1.54101e-08 1.62574e-08 ) ergs/cm2
Time-resolved spectra
