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 -73.608 sec. to 29.368 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.87224 ( -0.13364 0.130094 )
Norm@50keV : 2.70762E-03 ( -0.000221524 0.000218658 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.99 using 59 PHA bins.
# Reduced chi-squared = 0.9999 for 57 degrees of freedom
# Null hypothesis probability = 4.752809e-01
Photon flux (15-150 keV) in 103 sec: 0.384096 ( -0.027633 0.027665 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.56424e-06 ( -2.07575e-07 2.0996e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -73.608 sec. to 29.368 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.35697 ( -0.545546 0.634244 )
Epeak [keV] : 55.5965 ( -13.0826 -55.5965 )
Norm@50keV : 5.19533E-03 ( -0.0025382 0.00632753 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.44 using 59 PHA bins.
# Reduced chi-squared = 0.9721 for 56 degrees of freedom
# Null hypothesis probability = 5.342788e-01
Photon flux (15-150 keV) in 103 sec: 0.374636 ( -0.029461 0.029377 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.43903e-06 ( -2.42904e-07 2.46854e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.984 sec. to 3.984 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.71658 ( -0.267213 0.255243 )
Norm@50keV : 1.44921E-02 ( -0.00236442 0.00230367 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.14 using 59 PHA bins.
# Reduced chi-squared = 0.9498 for 57 degrees of freedom
# Null hypothesis probability = 5.831314e-01
Photon flux (15-150 keV) in 1 sec: 1.93608 ( -0.28436 0.28457 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.34032e-07 ( -2.25332e-08 2.28272e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.984 sec. to 3.984 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.65651 ( -1.25656 0.861946 )
Epeak [keV] : 275.255 ( )
Norm@50keV : 1.55920E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.16 using 59 PHA bins.
# Reduced chi-squared = 0.9672 for 56 degrees of freedom
# Null hypothesis probability = 5.447571e-01
Photon flux (15-150 keV) in 1 sec: 1.93854 ( -0.29393 0.28634 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.3436e-07 ( -2.42061e-08 1.94944e-08 ) ergs/cm2
Time-resolved spectra
