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 7.384 sec. to 105.616 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.79431 ( -0.228971 0.220187 )
Norm@50keV : 1.25148E-03 ( -0.000179721 0.000176454 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.55 using 59 PHA bins.
# Reduced chi-squared = 1.080 for 57 degrees of freedom
# Null hypothesis probability = 3.165263e-01
Photon flux (15-150 keV) in 98.23 sec: 0.172081 ( -0.022265 0.022293 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.13212e-06 ( -1.63945e-07 1.66446e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.384 sec. to 105.616 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.92987 ( -0.987465 1.50275 )
Epeak [keV] : 54.6574 ( -14.2136 -54.644 )
Norm@50keV : 3.77472E-03 ( -0.00377929 0.0224942 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.69 using 59 PHA bins.
# Reduced chi-squared = 1.066 for 56 degrees of freedom
# Null hypothesis probability = 3.432235e-01
Photon flux (15-150 keV) in 98.23 sec: 0.166418 ( -0.02374 0.023498 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.04622e-06 ( -1.91025e-07 1.97821e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 43.720 sec. to 44.720 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.47415 ( -0.55993 0.567032 )
Norm@50keV : 5.37725E-03 ( -0.00177269 0.00175438 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.26 using 59 PHA bins.
# Reduced chi-squared = 1.022 for 57 degrees of freedom
# Null hypothesis probability = 4.286962e-01
Photon flux (15-150 keV) in 1 sec: 0.666753 ( -0.221778 0.223147 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.12401e-08 ( -1.78975e-08 1.82911e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 43.720 sec. to 44.720 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.861071 ( -1.30778 4.21718 )
Epeak [keV] : 88.5025 ( -88.7399 -88.7399 )
Norm@50keV : 1.13656E-02 ( -0.0113152 1.5302 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.11 using 59 PHA bins.
# Reduced chi-squared = 1.038 for 56 degrees of freedom
# Null hypothesis probability = 3.974961e-01
Photon flux (15-150 keV) in 1 sec: 0.653873 ( -0.23514 0.229409 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.87158e-08 ( -2.02987e-08 1.998e-08 ) ergs/cm2
Time-resolved spectra
