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 -0.968 sec. to 46.648 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.03304 ( -0.19824 0.207175 )
Norm@50keV : 2.28507E-03 ( -0.000261864 0.000259613 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.61 using 59 PHA bins.
# Reduced chi-squared = 1.169 for 57 degrees of freedom
# Null hypothesis probability = 1.799329e-01
Photon flux (15-150 keV) in 47.62 sec: 0.263600 ( -0.031096 0.03127 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.16332e-06 ( -1.35351e-07 1.35892e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.968 sec. to 46.648 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.844352 ( -0.368182 0.966446 )
Epeak [keV] : 354.479 ( -354.69 -354.69 )
Norm@50keV : 2.76835E-03 ( -0.000713439 0.00429516 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.46 using 59 PHA bins.
# Reduced chi-squared = 1.187 for 56 degrees of freedom
# Null hypothesis probability = 1.598903e-01
Photon flux (15-150 keV) in 47.62 sec: 0.261282 ( -0.032862 0.032553 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.15244e-06 ( -1.46462e-07 1.42587e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 19.940 sec. to 20.940 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30789 ( -0.475409 0.492457 )
Norm@50keV : 6.11356E-03 ( -0.00172137 0.00172082 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.82 using 59 PHA bins.
# Reduced chi-squared = 1.295 for 57 degrees of freedom
# Null hypothesis probability = 6.637389e-02
Photon flux (15-150 keV) in 1 sec: 0.730443 ( -0.212249 0.213786 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.03045e-08 ( -1.82841e-08 1.86251e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 19.940 sec. to 20.940 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.116008 ( -1.58273 3.95522 )
Epeak [keV] : 82.7290 ( -59.3761 -82.7281 )
Norm@50keV : 2.29400E-02 ( -0.022941 1.2592 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.00 using 59 PHA bins.
# Reduced chi-squared = 1.303 for 56 degrees of freedom
# Null hypothesis probability = 6.314319e-02
Photon flux (15-150 keV) in 1 sec: 0.694741 ( -0.227602 0.225139 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.59887e-08 ( -1.92562e-08 2.03456e-08 ) ergs/cm2
Time-resolved spectra
