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 -55.980 sec. to 69.180 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.08518 ( -0.0852708 0.0837839 )
Norm@50keV : 2.72708E-03 ( -0.000132196 0.000131115 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.58 using 59 PHA bins.
# Reduced chi-squared = 0.8875 for 57 degrees of freedom
# Null hypothesis probability = 7.129094e-01
Photon flux (15-150 keV) in 125.2 sec: 0.425964 ( -0.019498 0.019574 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.16844e-06 ( -1.42469e-07 1.4306e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -55.980 sec. to 69.180 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.76608 ( -0.170635 0.35654 )
Epeak [keV] : 33.8723 ( -28.6419 13.1545 )
Norm@50keV : 4.02125E-03 ( -0.00101682 0.00214457 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.84 using 59 PHA bins.
# Reduced chi-squared = 0.8542 for 56 degrees of freedom
# Null hypothesis probability = 7.729770e-01
Photon flux (15-150 keV) in 125.2 sec: 0.416615 ( -0.021587 0.021634 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.07924e-06 ( -1.68364e-07 1.68594e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 24.604 sec. to 25.604 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.07889 ( -0.195408 0.185986 )
Norm@50keV : 1.21074E-02 ( -0.00158662 0.00155549 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.41 using 59 PHA bins.
# Reduced chi-squared = 0.9195 for 57 degrees of freedom
# Null hypothesis probability = 6.476844e-01
Photon flux (15-150 keV) in 1 sec: 1.88535 ( -0.20748 0.20772 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.12292e-07 ( -1.35413e-08 1.36846e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 24.604 sec. to 25.604 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.38721 ( -0.472841 0.847929 )
Epeak [keV] : 38.1340 ( )
Norm@50keV : 2.99777E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.57 using 59 PHA bins.
# Reduced chi-squared = 0.8851 for 56 degrees of freedom
# Null hypothesis probability = 7.154025e-01
Photon flux (15-150 keV) in 1 sec: 1.84923 ( -0.2109 0.21101 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
