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 -0.028 sec. to 0.460 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.86112 ( -0.323942 0.29613 )
Norm@50keV : 6.88163E-03 ( -0.00152562 0.00147839 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.11 using 59 PHA bins.
# Reduced chi-squared = 0.9318 for 57 degrees of freedom
# Null hypothesis probability = 6.216334e-01
Photon flux (15-150 keV) in 0.488 sec: 0.971741 ( -0.171439 0.171439 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.08802e-08 ( -6.64373e-09 6.87529e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.028 sec. to 0.460 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.679947 ( -1.31018 1.82233 )
Epeak [keV] : 45.8539 ( -17.1125 -45.8482 )
Norm@50keV : 3.39427E-02 ( -0.0339871 0.382067 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.88 using 59 PHA bins.
# Reduced chi-squared = 0.9086 for 56 degrees of freedom
# Null hypothesis probability = 6.685518e-01
Photon flux (15-150 keV) in 0.488 sec: 0.943885 ( -0.172674 0.174005 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.01453e-08 ( -9.11965e-09 5.15753e-09 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.282 sec. to 0.718 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.94013 ( -0.372436 0.335688 )
Norm@50keV : 3.72782E-03 ( -0.000997297 0.000975628 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.99 using 59 PHA bins.
# Reduced chi-squared = 0.8596 for 57 degrees of freedom
# Null hypothesis probability = 7.657147e-01
Photon flux (15-150 keV) in 1 sec: 0.544355 ( -0.11317 0.113223 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.42941e-08 ( -8.6404e-09 9.08694e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.282 sec. to 0.718 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.40708 ( -1.84809 2.87089 )
Epeak [keV] : 38.7735 ( -8.95256 16.2315 )
Norm@50keV : 0.101304 ( -0.108343 7.42331 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.70 using 59 PHA bins.
# Reduced chi-squared = 0.7803 for 56 degrees of freedom
# Null hypothesis probability = 8.842305e-01
Photon flux (15-150 keV) in 1 sec: 0.522898 ( -0.109749 0.111378 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.84702e-08 ( -7.29049e-09 8.95809e-09 ) ergs/cm2
Time-resolved spectra
