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 -17.260 sec. to 20.548 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.86726 ( -0.200155 0.193913 )
Norm@50keV : 1.36853E-03 ( -0.000173906 0.000171089 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 77.14 using 59 PHA bins.
# Reduced chi-squared = 1.353 for 57 degrees of freedom
# Null hypothesis probability = 3.902349e-02
Photon flux (15-150 keV) in 37.81 sec: 0.193736 ( -0.021222 0.021245 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.75782e-07 ( -5.95969e-08 6.07387e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -17.260 sec. to 20.548 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.881969 ( -0.908515 1.16592 )
Epeak [keV] : 46.5829 ( -10.3289 60.6852 )
Norm@50keV : 5.09928E-03 ( -0.00509995 0.0197131 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.70 using 59 PHA bins.
# Reduced chi-squared = 1.316 for 56 degrees of freedom
# Null hypothesis probability = 5.657957e-02
Photon flux (15-150 keV) in 37.81 sec: 0.185594 ( -0.022368 0.022465 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.24754e-07 ( -6.80837e-08 7.49088e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.108 sec. to 1.108 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.40239 ( -0.325935 0.326036 )
Norm@50keV : 6.05572E-03 ( -0.00107514 0.001071 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.13 using 59 PHA bins.
# Reduced chi-squared = 1.107 for 57 degrees of freedom
# Null hypothesis probability = 2.688608e-01
Photon flux (15-150 keV) in 1 sec: 0.737889 ( -0.134178 0.135004 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.84925e-08 ( -1.14121e-08 1.15804e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.108 sec. to 1.108 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.28751 ( -1.62693 1.22136 )
Epeak [keV] : 330.765 ( -260.938 -260.938 )
Norm@50keV : 6.86057E-03 ( -0.00175043 0.0193139 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.10 using 59 PHA bins.
# Reduced chi-squared = 1.127 for 56 degrees of freedom
# Null hypothesis probability = 2.398027e-01
Photon flux (15-150 keV) in 1 sec: 0.733796 ( -0.141799 0.138106 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.11882e-08 ( -1.4392e-08 1.01318e-08 ) ergs/cm2
Time-resolved spectra
