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 -29.736 sec. to 57.960 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.3332 ( -0.216466 0.218819 )
Norm@50keV : 1.01790E-03 ( -0.000122352 0.000121976 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 63.68 using 59 bins.
Reduced chi-squared = 1.11719
# Null hypothesis probability of 2.53e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 87.7 sec: 0.122213 ( -0.015064 0.015104 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.75326e-07 ( -1.16888e-07 1.17927e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -29.736 sec. to 57.960 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.31463 ( -1.18391 0.651048 )
Epeak [keV] : 9988.33 ( -9999.33 -9999.33 )
Norm@50keV : 1.03968E-03 ( -0.000789643 0.00101924 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 63.76 using 59 bins.
Reduced chi-squared = 1.13857
# Null hypothesis probability of 2.22e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 87.7 sec: 0.122654 ( -0.016859 0.015808 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.7878e-07 ( -1.31919e-07 1.23962e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.276 sec. to 0.724 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.2477 ( -0.317371 0.328865 )
Norm@50keV : 6.93682E-03 ( -0.0012536 0.00125305 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 35.19 using 59 bins.
Reduced chi-squared = 0.617368
# Null hypothesis probability of 9.90e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.820141 ( -0.152787 0.153324 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.94736e-08 ( -1.38678e-08 1.4029e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.276 sec. to 0.724 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.24373 ( -2.16246 1.12922 )
Epeak [keV] : 9998.63 ( -9998.71 -9998.71 )
Norm@50keV : 6.96834E-03 ( -0.00125939 0.0180178 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 35.19 using 59 bins.
Reduced chi-squared = 0.628393
# Null hypothesis probability of 9.87e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.820788 ( -0.153732 0.152371 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.95617e-08 ( -1.48135e-08 1.42684e-08 ) ergs/cm2
Time-resolved spectra
