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
Multiple GTIs in the spectrum
tstart tstop
-30.376000 18.375600
19.680000 135.288000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.56788 ( -0.240599 0.237517 )
Norm@50keV : 1.02244E-03 ( -0.000145223 0.000144264 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.93 using 59 PHA bins.
# Reduced chi-squared = 0.9988 for 57 degrees of freedom
# Null hypothesis probability = 4.776447e-01
Photon flux (15-150 keV) in 164.4 sec: 0.130119 ( -0.018636 0.018691 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.57871e-06 ( -2.38347e-07 2.40371e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-30.376000 18.375600
19.680000 135.288000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.16496 ( -0.619884 1.21356 )
Epeak [keV] : 104.125 ( -77.4542 -104.134 )
Norm@50keV : 1.63586E-03 ( -0.00163572 0.00486251 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.46 using 59 PHA bins.
# Reduced chi-squared = 1.008 for 56 degrees of freedom
# Null hypothesis probability = 4.576963e-01
Photon flux (15-150 keV) in 164.4 sec: 0.128029 ( -0.019489 0.019381 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.53848e-06 ( -2.618e-07 2.59321e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 37.132 sec. to 38.132 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.16745 ( -0.413042 0.453251 )
Norm@50keV : 8.65383E-03 ( -0.00201546 0.00195418 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.69 using 59 PHA bins.
# Reduced chi-squared = 0.8016 for 57 degrees of freedom
# Null hypothesis probability = 8.587638e-01
Photon flux (15-150 keV) in 1 sec: 1.01137 ( -0.24901 0.25139 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.86339e-08 ( -2.00898e-08 2.00912e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 37.132 sec. to 38.132 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.60014 ( 2.60037 2.49959 )
Epeak [keV] : 190.706 ( )
Norm@50keV : 1.37670E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.60 using 59 PHA bins.
# Reduced chi-squared = 0.8143 for 56 degrees of freedom
# Null hypothesis probability = 8.382258e-01
Photon flux (15-150 keV) in 1 sec: 1.01629 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.45697e-08 ( 0 0 ) ergs/cm2
Time-resolved spectra
