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 -0.440 sec. to 8.736 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.36219 ( -0.365421 0.372877 )
Norm@50keV : 2.19402E-03 ( -0.000435703 0.000432124 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 49.58 using 59 bins.
Reduced chi-squared = 0.869825
# Null hypothesis probability of 7.47e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 9.176 sec: 0.264990 ( -0.052567 0.052732 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.96125e-07 ( -4.3687e-08 4.45069e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.440 sec. to 8.736 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.61222 ( -1.24416 1.79551 )
Epeak [keV] : 193.925 ( )
Norm@50keV : 4.52697E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared 48.61 using 59 bins.
Reduced chi-squared = 0.868036
# Null hypothesis probability of 7.48e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 9.176 sec: 0.264986 ( -0.05266 0.052679 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.97767e-07 ( -5.68691e-08 5.48973e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 4.208 sec. to 5.208 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.24895 ( -0.627083 0.703693 )
Norm@50keV : 3.80841E-03 ( -0.00126052 0.00126038 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 45.19 using 59 bins.
Reduced chi-squared = 0.792807
# Null hypothesis probability of 8.71e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.450357 ( -0.154871 0.155536 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.81294e-08 ( -1.39085e-08 1.42536e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.208 sec. to 5.208 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.17547 ( -0.615329 1.10426 )
Epeak [keV] : 62.6657 ( -9999.36 -9999.36 )
Norm@50keV : 1.04367E-03 ( -0.00103916 0.0154383 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 44.93 using 59 bins.
Reduced chi-squared = 0.802321
# Null hypothesis probability of 8.56e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.451860 ( -0.157227 0.154811 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.86322e-08 ( -1.44971e-08 1.38111e-08 ) ergs/cm2
Time-resolved spectra
