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
Multiple GTIs in the spectrum
tstart tstop
-1.360000 79.842100
80.832000 310.172000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.96077 ( -0.227342 0.215901 )
Norm@50keV : 4.52427E-04 ( -6.1674e-05 5.92804e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.05 using 59 PHA bins.
# Reduced chi-squared = 1.159 for 57 degrees of freedom
# Null hypothesis probability = 1.925837e-01
Photon flux (15-150 keV) in 310.5 sec: 6.66732E-02 ( -0.0067141 0.0067176 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.29346e-06 ( -1.63682e-07 1.68255e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-1.360000 79.842100
80.832000 310.172000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.69236 ( -0.294575 0.66403 )
Epeak [keV] : 227.833 ( -61.1713 109.01 )
Norm@50keV : 2.03239E-04 ( -0.000105915 0.000180246 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.23 using 59 PHA bins.
# Reduced chi-squared = 1.111 for 56 degrees of freedom
# Null hypothesis probability = 2.640266e-01
Photon flux (15-150 keV) in 310.5 sec: 5.38966E-02 ( -0.0146018 0.0133595 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.22355e-06 ( -2.10778e-07 1.8727e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.144 sec. to 1.144 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.29997 ( -0.168911 0.168861 )
Norm@50keV : 1.39663E-02 ( -0.00142914 0.00142761 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.11 using 59 PHA bins.
# Reduced chi-squared = 1.230 for 57 degrees of freedom
# Null hypothesis probability = 1.139140e-01
Photon flux (15-150 keV) in 1 sec: 1.66623 ( -0.1725 0.17271 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.38029e-07 ( -1.56914e-08 1.58219e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.144 sec. to 1.144 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.336058 ( -0.757631 0.92838 )
Epeak [keV] : 89.7918 ( -22.1984 128.223 )
Norm@50keV : 4.12090E-02 ( -0.0232476 0.0722748 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.21 using 59 PHA bins.
# Reduced chi-squared = 1.164 for 56 degrees of freedom
# Null hypothesis probability = 1.871355e-01
Photon flux (15-150 keV) in 1 sec: 1.60531 ( -0.18076 0.17962 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.29876e-07 ( -1.72159e-08 1.72841e-08 ) ergs/cm2
Time-resolved spectra
