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 -74.036 sec. to 46.368 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.64309 ( -0.329535 0.312282 )
Norm@50keV : 5.60273E-04 ( -0.000106256 0.000101947 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 82.29 using 59 bins.
Reduced chi-squared = 1.44368
# Null hypothesis probability of 1.58e-02 with 57 degrees of freedom
Photon flux (15-150 keV) in 120.4 sec: 7.29948E-02 ( -0.0118604 0.0118661 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.27894e-07 ( -1.25359e-07 1.28828e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -74.036 sec. to 46.368 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.64708 ( -0.326613 0.319284 )
Epeak [keV] : 9999.36 ( -9999.35 -9999.36 )
Norm@50keV : 5.60435E-04 ( -0.000106027 0.000754743 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 82.29 using 59 bins.
Reduced chi-squared = 1.46946
# Null hypothesis probability of 1.26e-02 with 56 degrees of freedom
Photon flux (15-150 keV) in 120.4 sec: 7.31360E-02 ( -0.0120862 0.0118175 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.2762e-07 ( -1.24969e-07 1.28876e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.352 sec. to 1.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.34787 ( -0.338771 0.337288 )
Norm@50keV : 5.83821E-03 ( -0.00114738 0.00113923 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 53.76 using 59 bins.
Reduced chi-squared = 0.943158
# Null hypothesis probability of 5.97e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.703038 ( -0.137045 0.137272 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.70545e-08 ( -1.25207e-08 1.27286e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.352 sec. to 1.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.07922 ( -1.62878 1.52381 )
Epeak [keV] : 178.730 ( -178.736 -178.736 )
Norm@50keV : 7.91940E-03 ( -0.00318135 0.0332519 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 53.62 using 59 bins.
Reduced chi-squared = 0.9575
# Null hypothesis probability of 5.66e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.696168 ( -0.141238 0.140436 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.6119e-08 ( -1.32691e-08 1.32427e-08 ) ergs/cm2
Time-resolved spectra
