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 -0.012 sec. to 2.944 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.57525 ( -0.437845 0.373385 )
Norm@50keV : 3.90192E-03 ( -0.00123524 0.0012414 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.98 using 59 PHA bins.
# Reduced chi-squared = 0.9822 for 57 degrees of freedom
# Null hypothesis probability = 5.132147e-01
Photon flux (15-150 keV) in 2.956 sec: 0.803385 ( -0.149226 0.149261 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.1786e-07 ( -2.66702e-08 2.81679e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.012 sec. to 2.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.47581 ( -0.528009 2.20014 )
Epeak [keV] : 16.4707 ( )
Norm@50keV : 2.01258E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.48 using 59 PHA bins.
# Reduced chi-squared = 0.9729 for 56 degrees of freedom
# Null hypothesis probability = 5.325265e-01
Photon flux (15-150 keV) in 2.956 sec: 0.787945 ( -0.148271 0.149219 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.760 sec. to 1.760 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.41247 ( -0.522101 0.430476 )
Norm@50keV : 6.01523E-03 ( -0.00216122 0.00210676 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.47 using 59 PHA bins.
# Reduced chi-squared = 0.7802 for 57 degrees of freedom
# Null hypothesis probability = 8.866352e-01
Photon flux (15-150 keV) in 1 sec: 1.12128 ( -0.259307 0.25931 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.88586e-08 ( -1.61977e-08 1.70935e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.760 sec. to 1.760 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.661544 ( -1.90179 3.35024 )
Epeak [keV] : 28.0742 ( )
Norm@50keV : 7.38696E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.77 using 59 PHA bins.
# Reduced chi-squared = 0.7637 for 56 degrees of freedom
# Null hypothesis probability = 9.033151e-01
Photon flux (15-150 keV) in 1 sec: 1.12305 ( -0.261949 0.25711 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
