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 -6.852 sec. to 79.964 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.50395 ( -0.0572506 0.0571706 )
Norm@50keV : 5.59270E-03 ( -0.000159328 0.000159227 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.33 using 59 PHA bins.
# Reduced chi-squared = 0.8480 for 57 degrees of freedom
# Null hypothesis probability = 7.862816e-01
Photon flux (15-150 keV) in 86.82 sec: 0.698951 ( -0.021535 0.021635 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.60384e-06 ( -1.42042e-07 1.42512e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.852 sec. to 79.964 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.50128 ( -0.0589156 0.216346 )
Epeak [keV] : 9998.67 ( -9998.66 -9998.66 )
Norm@50keV : 5.60909E-03 ( -0.000159974 0.00142347 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.33 using 59 PHA bins.
# Reduced chi-squared = 0.8631 for 56 degrees of freedom
# Null hypothesis probability = 7.569991e-01
Photon flux (15-150 keV) in 86.82 sec: 0.698882 ( -0.02463 0.021299 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.60278e-06 ( -1.63937e-07 1.41057e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 36.556 sec. to 37.556 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.31356 ( -0.129308 0.128593 )
Norm@50keV : 2.24175E-02 ( -0.0015482 0.00154279 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.52 using 59 PHA bins.
# Reduced chi-squared = 1.062 for 57 degrees of freedom
# Null hypothesis probability = 3.499467e-01
Photon flux (15-150 keV) in 1 sec: 2.68129 ( -0.18284 0.18302 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.20826e-07 ( -1.77821e-08 1.79716e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 36.556 sec. to 37.556 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30974 ( -0.130255 0.225402 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 2.25086E-02 ( -0.00557999 0.00699578 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.55 using 59 PHA bins.
# Reduced chi-squared = 1.081 for 56 degrees of freedom
# Null hypothesis probability = 3.150511e-01
Photon flux (15-150 keV) in 1 sec: 2.69864 ( -0.20074 0.16509 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.22116e-07 ( -1.91936e-08 1.65882e-08 ) ergs/cm2
Time-resolved spectra
