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 -0.164 sec. to 0.832 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.339 ( -0.0817444 0.0818753 )
Norm@50keV : 8.99961E-02 ( -0.00434592 0.00434591 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.65 using 59 PHA bins.
# Reduced chi-squared = 1.047 for 57 degrees of freedom
# Null hypothesis probability = 3.795115e-01
Photon flux (15-150 keV) in 0.996 sec: 10.8179 ( -0.5523 0.5532 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.77747e-07 ( -4.52947e-08 4.53969e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.164 sec. to 0.832 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.971965 ( -0.321933 0.346363 )
Epeak [keV] : 156.107 ( -50.1575 562.258 )
Norm@50keV : 0.133118 ( -0.0378823 0.057304 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.83 using 59 PHA bins.
# Reduced chi-squared = 0.9970 for 56 degrees of freedom
# Null hypothesis probability = 4.812850e-01
Photon flux (15-150 keV) in 0.996 sec: 10.6583 ( -0.5685 0.5695 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.65625e-07 ( -4.71799e-08 4.70151e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.164 sec. to 0.836 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.34272 ( -0.0818164 0.08193 )
Norm@50keV : 8.97295E-02 ( -0.00433422 0.00433422 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.03 using 59 PHA bins.
# Reduced chi-squared = 1.036 for 57 degrees of freedom
# Null hypothesis probability = 4.010888e-01
Photon flux (15-150 keV) in 1 sec: 10.7939 ( -0.5511 0.552 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.7791e-07 ( -4.53223e-08 4.54478e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.164 sec. to 0.836 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.978508 ( -0.321917 0.346331 )
Epeak [keV] : 156.158 ( -50.4157 592.59 )
Norm@50keV : 0.132373 ( -0.0376984 0.0570547 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.27 using 59 PHA bins.
# Reduced chi-squared = 0.9870 for 56 degrees of freedom
# Null hypothesis probability = 5.023678e-01
Photon flux (15-150 keV) in 1 sec: 10.6356 ( -0.5674 0.5682 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.65785e-07 ( -4.7226e-08 4.70872e-08 ) ergs/cm2
Time-resolved spectra
