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 -83.148 sec. to 145.372 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.22092 ( -0.0378419 0.0380099 )
Norm@50keV : 7.39697E-03 ( -0.000151855 0.000151481 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 39.87 using 59 PHA bins.
# Reduced chi-squared = 0.6994 for 57 degrees of freedom
# Null hypothesis probability = 9.588245e-01
Photon flux (15-150 keV) in 228.5 sec: 0.870900 ( -0.019772 0.019835 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.70501e-05 ( -3.45088e-07 3.45396e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -83.148 sec. to 145.372 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.097 ( -0.136496 0.154272 )
Epeak [keV] : 444.655 ( -232.238 -444.864 )
Norm@50keV : 8.32018E-03 ( -0.000705883 0.00127367 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.88 using 59 PHA bins.
# Reduced chi-squared = 0.6764 for 56 degrees of freedom
# Null hypothesis probability = 9.697680e-01
Photon flux (15-150 keV) in 228.5 sec: 0.862829 ( -0.021823 0.021903 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.69561e-05 ( -3.64213e-07 3.63018e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 5.804 sec. to 6.804 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.917571 ( -0.0596312 0.0600957 )
Norm@50keV : 0.153214 ( -0.00521846 0.0052054 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.96 using 59 PHA bins.
# Reduced chi-squared = 0.8940 for 57 degrees of freedom
# Null hypothesis probability = 6.999014e-01
Photon flux (15-150 keV) in 1 sec: 0.980019 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.70805e-06 ( -6.27693e-08 6.29151e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.804 sec. to 6.804 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.745714 ( -0.196107 0.237456 )
Epeak [keV] : 432.987 ( -432.987 -432.987 )
Norm@50keV : 0.181846 ( -0.0305712 0.0468526 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.28 using 59 PHA bins.
# Reduced chi-squared = 0.8799 for 56 degrees of freedom
# Null hypothesis probability = 7.254437e-01
Photon flux (15-150 keV) in 1 sec: 17.4739 ( -0.6195 0.6196 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.69664e-06 ( -6.52042e-08 6.49709e-08 ) ergs/cm2
Time-resolved spectra
