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 15.180 sec. to 74.816 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.60367 ( -0.21286 0.207089 )
Norm@50keV : 9.23291E-04 ( -0.000121303 0.000119317 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 34.06 using 59 PHA bins.
# Reduced chi-squared = 0.5975 for 57 degrees of freedom
# Null hypothesis probability = 9.931980e-01
Photon flux (15-150 keV) in 59.64 sec: 0.118786 ( -0.014092 0.014096 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.14823e-07 ( -7.25628e-08 7.39769e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 15.180 sec. to 74.816 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.15647 ( -0.429555 0.957303 )
Epeak [keV] : 85.9277 ( -40.728 -85.9277 )
Norm@50keV : 1.62044E-03 ( -0.00079369 0.00376114 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 33.12 using 59 PHA bins.
# Reduced chi-squared = 0.5914 for 56 degrees of freedom
# Null hypothesis probability = 9.936149e-01
Photon flux (15-150 keV) in 59.64 sec: 0.116697 ( -0.014592 0.01456 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.91686e-07 ( -8.27475e-08 8.39099e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 30.452 sec. to 31.452 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.76938 ( -0.587009 0.511168 )
Norm@50keV : 2.52230E-03 ( -0.000957075 0.000914477 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.01 using 59 PHA bins.
# Reduced chi-squared = 0.9651 for 57 degrees of freedom
# Null hypothesis probability = 5.501029e-01
Photon flux (15-150 keV) in 1 sec: 0.343544 ( -0.106793 0.106794 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.32557e-08 ( -8.58773e-09 9.15586e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from 30.452 sec. to 31.452 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.529809 ( )
Epeak [keV] : 52.0836 ( )
Norm@50keV : 1.24797E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.86 using 59 PHA bins.
# Reduced chi-squared = 0.9618 for 56 degrees of freedom
# Null hypothesis probability = 5.561859e-01
Photon flux (15-150 keV) in 1 sec: 0.333302 ( -0.106131 0.107314 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.11958e-08 ( -8.20637e-09 9.5843e-09 ) ergs/cm2
Time-resolved spectra
