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 -13.632 sec. to 134.368 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.95256 ( -0.230686 0.219386 )
Norm@50keV : 7.43679E-04 ( -0.000106924 0.000103845 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.00 using 59 PHA bins.
# Reduced chi-squared = 0.6492 for 57 degrees of freedom
# Null hypothesis probability = 9.815691e-01
Photon flux (15-150 keV) in 148 sec: 0.109195 ( -0.012436 0.012446 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.01315e-06 ( -1.37493e-07 1.40631e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -13.632 sec. to 134.368 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.94703 ( -0.724369 0.915934 )
Epeak [keV] : 356.408 ( )
Norm@50keV : 7.48873E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.00 using 59 PHA bins.
# Reduced chi-squared = 0.6608 for 56 degrees of freedom
# Null hypothesis probability = 9.764699e-01
Photon flux (15-150 keV) in 148 sec: 0.109481 ( -0.0123789 0.012383 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02198e-06 ( -1.70582e-07 1.18775e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 50.860 sec. to 51.860 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.43741 ( -1.08139 0.813236 )
Norm@50keV : 2.18331E-03 ( -0.00218326 0.0013853 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.12 using 59 PHA bins.
# Reduced chi-squared = 1.353 for 57 degrees of freedom
# Null hypothesis probability = 3.920492e-02
Photon flux (15-150 keV) in 1 sec: 0.413040 ( -0.145714 0.14589 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.14902e-08 ( -9.70302e-09 1.13276e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 50.860 sec. to 51.860 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.84908 ( )
Epeak [keV] : 21.3692 ( )
Norm@50keV : 3.76509E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.93 using 59 PHA bins.
# Reduced chi-squared = 1.392 for 56 degrees of freedom
# Null hypothesis probability = 2.794911e-02
Photon flux (15-150 keV) in 1 sec: 0.319611 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.86226e-08 ( 0 0 ) ergs/cm2
Time-resolved spectra
