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 -2.768 sec. to 23.872 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.48355 ( -0.246246 0.246728 )
Norm@50keV : 3.57583E-03 ( -0.000527377 0.000525867 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 40.43 using 59 bins.
Reduced chi-squared = 0.709298
# Null hypothesis probability of 9.53e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 26.64 sec: 0.444471 ( -0.06738 0.067621 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.06285e-07 ( -1.43004e-07 1.44162e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.768 sec. to 23.872 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.920801 ( -0.753416 1.28655 )
Epeak [keV] : 95.8954 ( -38.3595 -95.9249 )
Norm@50keV : 6.91033E-03 ( -0.00375115 0.0234671 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 39.53 using 59 bins.
Reduced chi-squared = 0.705893
# Null hypothesis probability of 9.53e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 26.64 sec: 0.435409 ( -0.069693 0.0696 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.727e-07 ( -1.58739e-07 1.56629e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.868 sec. to 1.868 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.66578 ( -0.357869 0.342401 )
Norm@50keV : 1.34234E-02 ( -0.00304333 0.0029909 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 61.41 using 59 bins.
Reduced chi-squared = 1.07737
# Null hypothesis probability of 3.21e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 1.76207 ( -0.38008 0.38098 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.24669e-07 ( -2.92093e-08 2.9668e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.868 sec. to 1.868 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.189064 ( -1.70598 3.2731 )
Epeak [keV] : 56.3185 ( -10.9124 -56.0966 )
Norm@50keV : 8.36988E-02 ( -0.086747 4.73456 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 59.55 using 59 bins.
Reduced chi-squared = 1.06339
# Null hypothesis probability of 3.48e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 1.68166 ( -0.40579 0.39888 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.81008e-08 ( -3.86333e-08 2.33312e-08 ) ergs/cm2
Time-resolved spectra
