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 -62.232 sec. to 78.112 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.51318 ( -0.110903 0.110629 )
Norm@50keV : 2.47827E-03 ( -0.000163566 0.000163405 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 78.63 using 59 PHA bins.
# Reduced chi-squared = 1.379 for 57 degrees of freedom
# Null hypothesis probability = 3.037999e-02
Photon flux (15-150 keV) in 140.3 sec: 0.310503 ( -0.021311 0.021376 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.2919e-06 ( -2.31293e-07 2.32519e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -62.232 sec. to 78.112 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.230017 ( -0.556345 0.639781 )
Epeak [keV] : 69.9110 ( -9.09548 17.1524 )
Norm@50keV : 1.05884E-02 ( -0.00487054 0.0109526 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.46 using 59 PHA bins.
# Reduced chi-squared = 1.080 for 56 degrees of freedom
# Null hypothesis probability = 3.180118e-01
Photon flux (15-150 keV) in 140.3 sec: 0.290636 ( -0.022709 0.022815 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.01355e-06 ( -2.57493e-07 2.60296e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 3.776 sec. to 4.776 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.14498 ( -0.366774 0.39165 )
Norm@50keV : 9.65464E-03 ( -0.00213598 0.00210728 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.43 using 59 PHA bins.
# Reduced chi-squared = 0.9549 for 57 degrees of freedom
# Null hypothesis probability = 5.720802e-01
Photon flux (15-150 keV) in 1 sec: 1.12526 ( -0.26075 0.26483 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.95497e-08 ( -2.18409e-08 2.19122e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.776 sec. to 4.776 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.570443 ( 0.570443 2.15537 )
Epeak [keV] : 146.224 ( -146.224 -146.224 )
Norm@50keV : 1.71483E-02 ( -0.00933878 0.109641 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.05 using 59 PHA bins.
# Reduced chi-squared = 0.9652 for 56 degrees of freedom
# Null hypothesis probability = 5.489683e-01
Photon flux (15-150 keV) in 1 sec: 1.09560 ( -0.271105 0.27641 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.74967e-08 ( -2.31948e-08 2.27131e-08 ) ergs/cm2
Time-resolved spectra
