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 -0.744 sec. to 172.328 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.68028 ( -0.121233 0.120246 )
Norm@50keV : 3.85298E-03 ( -0.000263306 0.000262214 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.33 using 59 PHA bins.
# Reduced chi-squared = 0.9531 for 57 degrees of freedom
# Null hypothesis probability = 5.760370e-01
Photon flux (15-150 keV) in 173.1 sec: 0.508265 ( -0.035403 0.035528 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.18625e-06 ( -4.41684e-07 4.44417e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.744 sec. to 172.328 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.25169 ( -0.448127 0.509858 )
Epeak [keV] : 86.2332 ( -24.0875 -86.2332 )
Norm@50keV : 6.34368E-03 ( -0.00254416 0.00496884 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.74 using 59 PHA bins.
# Reduced chi-squared = 0.9240 for 56 degrees of freedom
# Null hypothesis probability = 6.365884e-01
Photon flux (15-150 keV) in 173.1 sec: 0.495435 ( -0.037832 0.037919 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.97238e-06 ( -4.96842e-07 4.97808e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 38.972 sec. to 39.972 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.97825 ( -0.427447 0.393283 )
Norm@50keV : 1.33106E-02 ( -0.00369396 0.00358678 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.63 using 59 PHA bins.
# Reduced chi-squared = 1.222 for 57 degrees of freedom
# Null hypothesis probability = 1.216185e-01
Photon flux (15-150 keV) in 1 sec: 1.97696 ( -0.4843 0.48629 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22651e-07 ( -3.20652e-08 3.28095e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 38.972 sec. to 39.972 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.656617 ( -2.62956 6.43949 )
Epeak [keV] : 40.1240 ( )
Norm@50keV : 0.467015 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.66 using 59 PHA bins.
# Reduced chi-squared = 1.190 for 56 degrees of freedom
# Null hypothesis probability = 1.557587e-01
Photon flux (15-150 keV) in 1 sec: 1.79371 ( -0.50953 0.53014 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.83717e-08 ( -2.864e-08 4.04796e-08 ) ergs/cm2
Time-resolved spectra
