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 -3.936 sec. to 35.064 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67637 ( -0.255331 0.245559 )
Norm@50keV : 1.46103E-03 ( -0.00022523 0.000219257 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.06 using 59 PHA bins.
# Reduced chi-squared = 0.9660 for 57 degrees of freedom
# Null hypothesis probability = 5.481231e-01
Photon flux (15-150 keV) in 39 sec: 0.192475 ( -0.025622 0.025629 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.28696e-07 ( -8.5348e-08 8.74942e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.936 sec. to 35.064 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.68176 ( -0.252233 0.251396 )
Epeak [keV] : 9999.36 ( -9999.35 -9999.36 )
Norm@50keV : 1.45833E-03 ( -0.000224904 0.0033752 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.07 using 59 PHA bins.
# Reduced chi-squared = 0.9833 for 56 degrees of freedom
# Null hypothesis probability = 5.102307e-01
Photon flux (15-150 keV) in 39 sec: 0.192977 ( -0.027281 0.025854 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.32015e-07 ( -1.06617e-07 6.46148e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.064 sec. to 3.064 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11468 ( -0.488235 0.514402 )
Norm@50keV : 4.96283E-03 ( -0.00132721 0.00132394 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.85 using 59 PHA bins.
# Reduced chi-squared = 1.015 for 57 degrees of freedom
# Null hypothesis probability = 4.436245e-01
Photon flux (15-150 keV) in 1 sec: 0.576500 ( -0.158142 0.159201 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.16523e-08 ( -1.51626e-08 1.54319e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.064 sec. to 3.064 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11323 ( -0.48941 0.520441 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 4.98748E-03 ( -0.0013267 0.101255 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.85 using 59 PHA bins.
# Reduced chi-squared = 1.033 for 56 degrees of freedom
# Null hypothesis probability = 4.067130e-01
Photon flux (15-150 keV) in 1 sec: 0.577630 ( -0.170748 0.158733 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.17595e-08 ( -1.69923e-08 1.36815e-08 ) ergs/cm2
Time-resolved spectra
