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 -0.328 sec. to 0.232 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.550099 ( -0.218246 0.233525 )
Norm@50keV : 2.49533E-02 ( -0.0033762 0.00326604 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 62.11 using 59 bins.
Reduced chi-squared = 1.08965
# Null hypothesis probability of 2.99e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 0.56 sec: 0.162922 ( -0.006268 0.223274 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.83108e-07 ( -2.104e-08 2.10928e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.328 sec. to 0.232 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.530727 ( -0.229854 0.966565 )
Epeak [keV] : 9899.14 ( -9744.19 -9744.19 )
Norm@50keV : 2.50859E-02 ( -0.00311991 0.0291357 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 62.11 using 59 bins.
Reduced chi-squared = 1.10911
# Null hypothesis probability of 2.68e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 0.56 sec: 2.92979 ( -0.36721 0.32443 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.98038e-07 ( -3.66064e-08 6.27609e-09 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.540 sec. to 0.460 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.665549 ( -0.224616 0.239547 )
Norm@50keV : 1.59596E-02 ( -0.00221097 0.00214708 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 53.86 using 59 bins.
Reduced chi-squared = 0.944912
# Null hypothesis probability of 5.94e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 1.85025 ( -0.23222 0.23442 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.97911e-07 ( -2.37865e-08 2.38474e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.540 sec. to 0.460 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.376117 ( -0.485296 1.04548 )
Epeak [keV] : 377.540 ( -377.538 -377.538 )
Norm@50keV : 2.03737E-02 ( -0.00580276 0.025942 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 53.54 using 59 bins.
Reduced chi-squared = 0.956071
# Null hypothesis probability of 5.68e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 1.82371 ( -0.24372 0.24693 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.96648e-07 ( -2.44849e-08 2.42593e-08 ) ergs/cm2
Time-resolved spectra
