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 6.056 sec. to 64.680 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.60502 ( -0.178122 0.175265 )
Norm@50keV : 1.73961E-03 ( -0.000205705 0.000204003 )
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#Fit statistic : Chi-Squared = 66.37 using 59 PHA bins.
# Reduced chi-squared = 1.164 for 57 degrees of freedom
# Null hypothesis probability = 1.853684e-01
Photon flux (15-150 keV) in 58.62 sec: 0.223903 ( -0.024741 0.024755 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.5329e-07 ( -1.19867e-07 1.21679e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 6.056 sec. to 64.680 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.0324951 ( -0.890549 1.12314 )
Epeak [keV] : 54.2377 ( -8.44761 17.2256 )
Norm@50keV : 1.42552E-02 ( -0.0142558 0.0465513 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.69 using 59 PHA bins.
# Reduced chi-squared = 0.9766 for 56 degrees of freedom
# Null hypothesis probability = 5.246134e-01
Photon flux (15-150 keV) in 58.62 sec: 0.213020 ( -0.025143 0.025249 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.24854e-07 ( -1.22452e-07 1.32508e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 26.324 sec. to 27.324 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.14673 ( -0.668697 0.548754 )
Norm@50keV : 3.17762E-03 ( -0.00153036 0.00152652 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.87 using 59 PHA bins.
# Reduced chi-squared = 0.8924 for 57 degrees of freedom
# Null hypothesis probability = 7.031567e-01
Photon flux (15-150 keV) in 1 sec: 0.511649 ( -0.186887 0.187464 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.95726e-08 ( -1.24823e-08 1.35992e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 26.324 sec. to 27.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.10317 ( -2.76109 -1.15335 )
Epeak [keV] : 35.0124 ( )
Norm@50keV : 0.351311 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.49 using 59 PHA bins.
# Reduced chi-squared = 0.8301 for 56 degrees of freedom
# Null hypothesis probability = 8.136660e-01
Photon flux (15-150 keV) in 1 sec: 0.519888 ( -0.177628 0.179904 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.62349e-08 ( -1.01899e-08 1.16303e-08 ) ergs/cm2
Time-resolved spectra
