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 -2.960 sec. to 5.328 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.78539 ( -0.323164 0.3044 )
Norm@50keV : 2.72359E-03 ( -0.000566875 0.000550322 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.17 using 59 PHA bins.
# Reduced chi-squared = 0.8275 for 57 degrees of freedom
# Null hypothesis probability = 8.203205e-01
Photon flux (15-150 keV) in 8.288 sec: 0.373219 ( -0.066773 0.066804 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.0796e-07 ( -4.32918e-08 4.43763e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.960 sec. to 5.328 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30275 ( -0.788425 1.2137 )
Epeak [keV] : 65.5973 ( -50.3606 -65.53 )
Norm@50keV : 5.02233E-03 ( -0.00503294 0.0179071 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.47 using 59 PHA bins.
# Reduced chi-squared = 0.8299 for 56 degrees of freedom
# Null hypothesis probability = 8.140275e-01
Photon flux (15-150 keV) in 8.288 sec: 0.367942 ( -0.067493 0.067596 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.0024e-07 ( -4.51405e-08 4.68642e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.916 sec. to 1.916 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30185 ( -0.343366 0.347462 )
Norm@50keV : 7.93181E-03 ( -0.0016454 0.00164409 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.37 using 59 PHA bins.
# Reduced chi-squared = 0.9364 for 57 degrees of freedom
# Null hypothesis probability = 6.119647e-01
Photon flux (15-150 keV) in 1 sec: 0.946617 ( -0.20268 0.203503 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.83556e-08 ( -1.75589e-08 1.7706e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.916 sec. to 1.916 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.525831 ( -0.97253 1.91715 )
Epeak [keV] : 105.624 ( )
Norm@50keV : 1.81230E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.43 using 59 PHA bins.
# Reduced chi-squared = 0.9363 for 56 degrees of freedom
# Null hypothesis probability = 6.107376e-01
Photon flux (15-150 keV) in 1 sec: 0.920419 ( -0.210968 0.209471 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.61868e-08 ( -1.80809e-08 1.82519e-08 ) ergs/cm2
Time-resolved spectra
