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 -28.824 sec. to 371.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.20637 ( -0.138784 0.13364 )
Norm@50keV : 8.87783E-04 ( -7.95136e-05 7.84258e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.36 using 59 PHA bins.
# Reduced chi-squared = 1.024 for 57 degrees of freedom
# Null hypothesis probability = 4.250403e-01
Photon flux (15-150 keV) in 400 sec: 0.147484 ( -0.009575 0.009584 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.34249e-06 ( -2.54042e-07 2.58569e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -28.824 sec. to 371.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.71967 ( -0.283565 0.637311 )
Epeak [keV] : 22.8673 ( -22.0394 12.9864 )
Norm@50keV : 1.71830E-03 ( -0.000659424 0.0023513 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.11 using 59 PHA bins.
# Reduced chi-squared = 1.002 for 56 degrees of freedom
# Null hypothesis probability = 4.706460e-01
Photon flux (15-150 keV) in 400 sec: 0.143756 ( -0.010399 0.010103 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.15566e-06 ( -3.08774e-07 3.26751e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 90.676 sec. to 91.676 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.25497 ( -0.556328 0.457902 )
Norm@50keV : 4.06798E-03 ( -0.00155314 0.00150487 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.14 using 59 PHA bins.
# Reduced chi-squared = 0.9499 for 57 degrees of freedom
# Null hypothesis probability = 5.829448e-01
Photon flux (15-150 keV) in 1 sec: 0.693615 ( -0.161341 0.161571 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.8578e-08 ( -1.17196e-08 1.26987e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 90.676 sec. to 91.676 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.27433 ( -1.2872 3.29903 )
Epeak [keV] : 441.886 ( )
Norm@50keV : 3.95143E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.14 using 59 PHA bins.
# Reduced chi-squared = 0.9668 for 56 degrees of freedom
# Null hypothesis probability = 5.454594e-01
Photon flux (15-150 keV) in 1 sec: 0.693616 ( -0.160902 0.162575 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
