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 -1.352 sec. to 66.920 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.75833 ( -0.0914572 0.0903316 )
Norm@50keV : 3.41591E-03 ( -0.000182041 0.000180982 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.95 using 59 PHA bins.
# Reduced chi-squared = 1.157 for 57 degrees of freedom
# Null hypothesis probability = 1.949467e-01
Photon flux (15-150 keV) in 68.27 sec: 0.463337 ( -0.023694 0.023733 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.15119e-06 ( -1.18183e-07 1.18931e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.352 sec. to 66.920 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.25447 ( -0.384544 0.426583 )
Epeak [keV] : 69.3800 ( -13.6638 69.0629 )
Norm@50keV : 6.29540E-03 ( -0.00230502 0.00419765 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.82 using 59 PHA bins.
# Reduced chi-squared = 1.086 for 56 degrees of freedom
# Null hypothesis probability = 3.064240e-01
Photon flux (15-150 keV) in 68.27 sec: 0.450694 ( -0.025532 0.025513 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.05381e-06 ( -1.39155e-07 1.39401e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.184 sec. to 1.184 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.38761 ( -0.0853585 0.0851773 )
Norm@50keV : 4.97478E-02 ( -0.00255769 0.00255696 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.58 using 59 PHA bins.
# Reduced chi-squared = 1.273 for 57 degrees of freedom
# Null hypothesis probability = 7.993151e-02
Photon flux (15-150 keV) in 1 sec: 6.04164 ( -0.32231 0.32272 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.81992e-07 ( -2.67944e-08 2.687e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.184 sec. to 1.184 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.818999 ( -0.352749 0.382876 )
Epeak [keV] : 111.534 ( -25.3485 90.5436 )
Norm@50keV : 9.30952E-02 ( -0.0293755 0.0473682 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.67 using 59 PHA bins.
# Reduced chi-squared = 1.155 for 56 degrees of freedom
# Null hypothesis probability = 1.997976e-01
Photon flux (15-150 keV) in 1 sec: 5.91524 ( -0.33119 0.33149 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.69678e-07 ( -2.84836e-08 2.83572e-08 ) ergs/cm2
Time-resolved spectra
