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 -6.168 sec. to 73.384 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.60548 ( -0.136244 0.134709 )
Norm@50keV : 7.26353E-03 ( -0.000579458 0.000578118 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.54 using 59 PHA bins.
# Reduced chi-squared = 1.167 for 57 degrees of freedom
# Null hypothesis probability = 1.814761e-01
Photon flux (15-150 keV) in 79.55 sec: 0.935017 ( -0.077859 0.078123 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.40095e-06 ( -4.52035e-07 4.54227e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.168 sec. to 73.384 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.17896 ( -0.482186 0.577609 )
Epeak [keV] : 101.572 ( -33.8657 -101.572 )
Norm@50keV : 1.16915E-02 ( -0.00471181 0.0101825 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.57 using 59 PHA bins.
# Reduced chi-squared = 1.153 for 56 degrees of freedom
# Null hypothesis probability = 2.021598e-01
Photon flux (15-150 keV) in 79.55 sec: 0.916143 ( -0.080923 0.081201 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.29005e-06 ( -4.77336e-07 4.76022e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 11.164 sec. to 12.164 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.62711 ( -0.454516 0.431896 )
Norm@50keV : 1.98715E-02 ( -0.00522379 0.00518065 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.95 using 59 PHA bins.
# Reduced chi-squared = 1.034 for 57 degrees of freedom
# Null hypothesis probability = 4.040835e-01
Photon flux (15-150 keV) in 1 sec: 2.57559 ( -0.69839 0.70457 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.85285e-07 ( -5.04788e-08 5.08661e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 11.164 sec. to 12.164 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.13634 ( -0.50922 4.55228 )
Epeak [keV] : 53.9386 ( )
Norm@50keV : 8.84908E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.48 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 56 degrees of freedom
# Null hypothesis probability = 3.844470e-01
Photon flux (15-150 keV) in 1 sec: 2.51069 ( -0.7396 0.73264 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.80892e-07 ( -5.60847e-08 5.29971e-08 ) ergs/cm2
Time-resolved spectra
