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 -79.728 sec. to 37.272 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.45777 ( -0.12149 0.122295 )
Norm@50keV : 4.39700E-03 ( -0.00030383 0.000303667 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.74 using 59 PHA bins.
# Reduced chi-squared = 1.031 for 57 degrees of freedom
# Null hypothesis probability = 4.115180e-01
Photon flux (15-150 keV) in 117 sec: 0.542933 ( -0.039992 0.040104 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.91649e-06 ( -3.61728e-07 3.63289e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -79.728 sec. to 37.272 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.45444 ( -0.176962 0.417854 )
Epeak [keV] : 8969.30 ( -8894.61 -8894.61 )
Norm@50keV : 4.41381E-03 ( -0.000306443 0.00301079 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.74 using 59 PHA bins.
# Reduced chi-squared = 1.049 for 56 degrees of freedom
# Null hypothesis probability = 3.754294e-01
Photon flux (15-150 keV) in 117 sec: 0.542598 ( -0.041354 0.040517 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.9122e-06 ( -3.87539e-07 3.66245e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.272 sec. to 2.272 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.20511 ( -0.226142 0.235644 )
Norm@50keV : 2.83008E-02 ( -0.0037532 0.00374399 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.24 using 59 PHA bins.
# Reduced chi-squared = 1.232 for 57 degrees of freedom
# Null hypothesis probability = 1.119084e-01
Photon flux (15-150 keV) in 1 sec: 3.32436 ( -0.46548 0.46817 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.86741e-07 ( -3.99382e-08 4.01026e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.272 sec. to 2.272 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.41284 ( -0.224518 0.294203 )
Epeak [keV] : 135.511 ( -9999.36 -9999.36 )
Norm@50keV : 4.08136E-03 ( -0.00407692 0.0060101 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.63 using 59 PHA bins.
# Reduced chi-squared = 1.243 for 56 degrees of freedom
# Null hypothesis probability = 1.042650e-01
Photon flux (15-150 keV) in 1 sec: 3.32871 ( -0.47892 0.47127 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.87184e-07 ( -4.05971e-08 3.51751e-08 ) ergs/cm2
Time-resolved spectra
