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 -5.404 sec. to 158.944 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67634 ( -0.173791 0.170767 )
Norm@50keV : 1.37546E-03 ( -0.000134434 0.000133002 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 86.53 using 59 PHA bins.
# Reduced chi-squared = 1.518 for 57 degrees of freedom
# Null hypothesis probability = 7.045526e-03
Photon flux (15-150 keV) in 164.3 sec: 0.181200 ( -0.017275 0.01733 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.09694e-06 ( -2.15083e-07 2.17024e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -5.404 sec. to 158.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67316 ( -0.175044 0.171076 )
Epeak [keV] : 9999.31 ( -9999.35 -9999.36 )
Norm@50keV : 1.37788E-03 ( -0.000478427 0.00114361 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 86.53 using 59 PHA bins.
# Reduced chi-squared = 1.545 for 56 degrees of freedom
# Null hypothesis probability = 5.494539e-03
Photon flux (15-150 keV) in 164.3 sec: 0.181809 ( -0.019387 0.017988 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.10449e-06 ( -2.41766e-07 2.25577e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 82.680 sec. to 83.680 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.34828 ( -0.528306 0.55013 )
Norm@50keV : 5.02284E-03 ( -0.0016004 0.00160039 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.20 using 59 PHA bins.
# Reduced chi-squared = 1.232 for 57 degrees of freedom
# Null hypothesis probability = 1.125036e-01
Photon flux (15-150 keV) in 1 sec: 0.604911 ( -0.201245 0.204071 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.90806e-08 ( -1.64722e-08 1.67503e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 82.680 sec. to 83.680 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.0521886 ( -2.21152 3.86852 )
Epeak [keV] : 79.1068 ( )
Norm@50keV : 2.09816E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.20 using 59 PHA bins.
# Reduced chi-squared = 1.236 for 56 degrees of freedom
# Null hypothesis probability = 1.107717e-01
Photon flux (15-150 keV) in 1 sec: 0.572856 ( -0.20674 0.211352 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.5589e-08 ( -1.71948e-08 1.78988e-08 ) ergs/cm2
Time-resolved spectra
