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
-0.388000 2.728800
3.600000 310.464000
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.62864 ( -0.0541709 0.0540294 )
Norm@50keV : 3.19001E-03 ( -8.62583e-05 8.61768e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.34 using 59 PHA bins.
# Reduced chi-squared = 1.059 for 57 degrees of freedom
# Null hypothesis probability = 3.558693e-01
Photon flux (15-150 keV) in 310 sec: 0.413666 ( -0.012391 0.012439 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.21915e-06 ( -2.6217e-07 2.62668e-07 ) ergs/cm2
Cutoff power-law model
Multiple GTIs in the spectrum
tstart tstop
-0.388000 2.728800
3.600000 310.464000
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.6267 ( -0.0719356 0.129511 )
Epeak [keV] : 9999.36 ( -9999.35 -9999.36 )
Norm@50keV : 3.19705E-03 ( -8.66233e-05 0.000496574 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.37 using 59 PHA bins.
# Reduced chi-squared = 1.078 for 56 degrees of freedom
# Null hypothesis probability = 3.209149e-01
Photon flux (15-150 keV) in 310 sec: 0.416287 ( -0.014745 0.00977 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.27622e-06 ( -1.93382e-07 1.98613e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 13.412 sec. to 14.412 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.29248 ( -0.053072 0.0530887 )
Norm@50keV : 0.116061 ( -0.00346143 0.00346141 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.20 using 59 PHA bins.
# Reduced chi-squared = 0.8281 for 57 degrees of freedom
# Null hypothesis probability = 8.192800e-01
Photon flux (15-150 keV) in 1 sec: 0.439072 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14916e-06 ( -3.72747e-08 3.73188e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 13.412 sec. to 14.412 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.917261 ( -0.216402 0.227248 )
Epeak [keV] : 161.283 ( -40.4108 135.387 )
Norm@50keV : 0.172109 ( -0.0341799 0.0449787 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.17 using 59 PHA bins.
# Reduced chi-squared = 0.6815 for 56 degrees of freedom
# Null hypothesis probability = 9.672778e-01
Photon flux (15-150 keV) in 1 sec: 13.5576 ( -0.4581 0.4589 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.12694e-06 ( -3.98888e-08 3.97622e-08 ) ergs/cm2
Time-resolved spectra
