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 -31.624 sec. to 15.368 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.74123 ( -0.0958005 0.0945525 )
Norm@50keV : 3.22014E-03 ( -0.000177488 0.000176148 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.81 using 59 PHA bins.
# Reduced chi-squared = 1.049 for 57 degrees of freedom
# Null hypothesis probability = 3.741059e-01
Photon flux (15-150 keV) in 46.99 sec: 0.434038 ( -0.022115 0.022141 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.39716e-06 ( -8.00686e-08 8.08111e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -31.624 sec. to 15.368 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.45153 ( -0.331459 0.409521 )
Epeak [keV] : 86.9568 ( -27.5153 -86.96 )
Norm@50keV : 4.60164E-03 ( -0.0014838 0.00295826 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.07 using 59 PHA bins.
# Reduced chi-squared = 1.037 for 56 degrees of freedom
# Null hypothesis probability = 3.988830e-01
Photon flux (15-150 keV) in 46.99 sec: 0.426725 ( -0.024008 0.023963 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.35358e-06 ( -9.72496e-08 9.75423e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.024 sec. to 1.024 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.60385 ( -0.0812116 0.0804759 )
Norm@50keV : 3.69465E-02 ( -0.00174194 0.00173616 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.94 using 59 PHA bins.
# Reduced chi-squared = 0.8410 for 57 degrees of freedom
# Null hypothesis probability = 7.981055e-01
Photon flux (15-150 keV) in 1 sec: 4.75364 ( -0.22162 0.22188 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.45414e-07 ( -1.74471e-08 1.75387e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.024 sec. to 1.024 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11032 ( -0.323267 0.348155 )
Epeak [keV] : 89.8663 ( -18.8944 72.5026 )
Norm@50keV : 6.55137E-02 ( -0.0200511 0.0317385 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.88 using 59 PHA bins.
# Reduced chi-squared = 0.7300 for 56 degrees of freedom
# Null hypothesis probability = 9.354556e-01
Photon flux (15-150 keV) in 1 sec: 4.63325 ( -0.23428 0.23441 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.32767e-07 ( -1.93302e-08 1.93605e-08 ) ergs/cm2
Time-resolved spectra
