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 0.040 sec. to 0.588 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.483733 ( -0.223854 0.241854 )
Norm@50keV : 1.08415E-02 ( -0.0015633 0.00152089 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.43 using 59 PHA bins.
# Reduced chi-squared = 1.288 for 57 degrees of freedom
# Null hypothesis probability = 7.042899e-02
Photon flux (15-150 keV) in 0.548 sec: 1.28747 ( -0.16201 0.16262 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.04913e-08 ( -1.03699e-08 1.04163e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.040 sec. to 0.588 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.282657 ( -0.851151 1.28846 )
Epeak [keV] : 190.291 ( )
Norm@50keV : 2.16014E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.74 using 59 PHA bins.
# Reduced chi-squared = 1.281 for 56 degrees of freedom
# Null hypothesis probability = 7.656385e-02
Photon flux (15-150 keV) in 0.548 sec: 1.25487 ( -0.16794 0.16815 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.83919e-08 ( -1.12984e-08 1.1021e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.184 sec. to 0.816 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.530925 ( -0.265293 0.289923 )
Norm@50keV : 6.48981E-03 ( -0.00108351 0.00104654 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.32 using 59 PHA bins.
# Reduced chi-squared = 1.023 for 57 degrees of freedom
# Null hypothesis probability = 4.264378e-01
Photon flux (15-150 keV) in 1 sec: 0.764870 ( -0.111772 0.112357 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.58539e-08 ( -1.27938e-08 1.28604e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.184 sec. to 0.816 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.0804961 ( -0.566834 1.5066 )
Epeak [keV] : 272.780 ( -272.766 -272.766 )
Norm@50keV : 9.72895E-03 ( -0.00413146 0.0246226 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.90 using 59 PHA bins.
# Reduced chi-squared = 1.034 for 56 degrees of freedom
# Null hypothesis probability = 4.049557e-01
Photon flux (15-150 keV) in 1 sec: 0.751853 ( -0.117276 0.117182 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.45026e-08 ( -1.38741e-08 1.34216e-08 ) ergs/cm2
Time-resolved spectra
