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 -22.580 sec. to 215.728 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.99952 ( -0.0801652 0.078984 )
Norm@50keV : 2.51367E-03 ( -0.000113995 0.000113216 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.29 using 59 PHA bins.
# Reduced chi-squared = 1.023 for 57 degrees of freedom
# Null hypothesis probability = 4.277966e-01
Photon flux (15-150 keV) in 238.3 sec: 0.376996 ( -0.016259 0.016314 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.52477e-06 ( -2.39418e-07 2.40426e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -22.580 sec. to 215.728 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.57979 ( -0.327656 0.357874 )
Epeak [keV] : 46.0949 ( -13.6324 14.9828 )
Norm@50keV : 4.19107E-03 ( -0.00135209 0.00226045 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.41 using 59 PHA bins.
# Reduced chi-squared = 0.9537 for 56 degrees of freedom
# Null hypothesis probability = 5.735962e-01
Photon flux (15-150 keV) in 238.3 sec: 0.366262 ( -0.018131 0.018193 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.30804e-06 ( -2.90576e-07 2.90881e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 99.212 sec. to 100.212 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.95087 ( -0.19526 0.18624 )
Norm@50keV : 1.15087E-02 ( -0.0014167 0.00138167 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.69 using 59 PHA bins.
# Reduced chi-squared = 0.8366 for 57 degrees of freedom
# Null hypothesis probability = 8.055118e-01
Photon flux (15-150 keV) in 1 sec: 1.68856 ( -0.16398 0.16408 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.05933e-07 ( -1.23687e-08 1.26111e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 99.212 sec. to 100.212 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.90266 ( )
Epeak [keV] : 87.5429 ( )
Norm@50keV : 1.22538E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.67 using 59 PHA bins.
# Reduced chi-squared = 0.8513 for 56 degrees of freedom
# Null hypothesis probability = 7.781653e-01
Photon flux (15-150 keV) in 1 sec: 1.68488 ( -0.17085 0.16699 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
