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 -2.296 sec. to 71.688 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.41329 ( -0.224352 0.223277 )
Norm@50keV : 1.20912E-03 ( -0.000160086 0.000159319 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.93 using 59 PHA bins.
# Reduced chi-squared = 0.8410 for 57 degrees of freedom
# Null hypothesis probability = 7.982454e-01
Photon flux (15-150 keV) in 73.98 sec: 0.147701 ( -0.019436 0.019468 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.62133e-07 ( -1.26089e-07 1.27842e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.296 sec. to 71.688 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.575677 ( -0.921908 1.26289 )
Epeak [keV] : 84.8346 ( -24.0679 -84.8079 )
Norm@50keV : 3.19071E-03 ( -0.00319325 0.00988342 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.86 using 59 PHA bins.
# Reduced chi-squared = 0.8188 for 56 degrees of freedom
# Null hypothesis probability = 8.313351e-01
Photon flux (15-150 keV) in 73.98 sec: 0.142127 ( -0.020783 0.020625 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.0633e-07 ( -1.39655e-07 1.43737e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 41.012 sec. to 42.012 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.44507 ( -0.672477 0.672446 )
Norm@50keV : 3.76973E-03 ( -0.00141928 0.0013806 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.42 using 59 PHA bins.
# Reduced chi-squared = 0.9898 for 57 degrees of freedom
# Null hypothesis probability = 4.969213e-01
Photon flux (15-150 keV) in 1 sec: 0.464012 ( -0.16846 0.169326 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.6111e-08 ( -1.44833e-08 1.51622e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 41.012 sec. to 42.012 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10847 ( )
Epeak [keV] : 129.773 ( )
Norm@50keV : 5.62007E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.41 using 59 PHA bins.
# Reduced chi-squared = 1.007 for 56 degrees of freedom
# Null hypothesis probability = 4.596754e-01
Photon flux (15-150 keV) in 1 sec: 0.460207 ( -0.173168 0.172059 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.55189e-08 ( -1.54622e-08 1.55892e-08 ) ergs/cm2
Time-resolved spectra
