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 -15.460 sec. to 3.128 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.98956 ( -0.343733 0.312456 )
Norm@50keV : 1.79848E-03 ( -0.000427002 0.00041375 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.28 using 59 PHA bins.
# Reduced chi-squared = 1.233 for 57 degrees of freedom
# Null hypothesis probability = 1.112693e-01
Photon flux (15-150 keV) in 18.59 sec: 0.268505 ( -0.048201 0.0482 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.08218e-07 ( -6.75166e-08 7.02148e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.460 sec. to 3.128 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.09512 ( -1.09177 2.05266 )
Epeak [keV] : 39.0931 ( )
Norm@50keV : 6.32491E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.95 using 59 PHA bins.
# Reduced chi-squared = 1.231 for 56 degrees of freedom
# Null hypothesis probability = 1.145580e-01
Photon flux (15-150 keV) in 18.59 sec: 0.262298 ( -0.048672 0.048983 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.78869e-07 ( -7.254e-08 8.16099e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.164 sec. to 0.836 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.42737 ( -0.217519 0.214755 )
Norm@50keV : 1.29492E-02 ( -0.00191838 0.00191136 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.71 using 59 PHA bins.
# Reduced chi-squared = 1.170 for 57 degrees of freedom
# Null hypothesis probability = 1.777593e-01
Photon flux (15-150 keV) in 1 sec: 1.58711 ( -0.23249 0.23275 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.24454e-07 ( -1.99339e-08 2.01399e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.164 sec. to 0.836 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.452103 ( -1.07351 1.39915 )
Epeak [keV] : 65.2387 ( -11.3414 24.4028 )
Norm@50keV : 0.115866 ( -0.115865 0.440154 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.33 using 59 PHA bins.
# Reduced chi-squared = 1.006 for 56 degrees of freedom
# Null hypothesis probability = 4.624742e-01
Photon flux (15-150 keV) in 1 sec: 1.53016 ( -0.23415 0.23494 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14839e-07 ( -1.99185e-08 2.07111e-08 ) ergs/cm2
Time-resolved spectra
