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 24.424 sec. to 273.624 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.1141 ( -0.262904 0.241773 )
Norm@50keV : 1.02293E-03 ( -0.000178983 0.000173412 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.46 using 59 PHA bins.
# Reduced chi-squared = 0.9028 for 57 degrees of freedom
# Null hypothesis probability = 6.821570e-01
Photon flux (15-150 keV) in 249.2 sec: 0.162076 ( -0.0201 0.020102 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.37218e-06 ( -3.62683e-07 3.73548e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 24.424 sec. to 273.624 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.81641 ( -0.61266 1.12352 )
Epeak [keV] : 25.0485 ( -23.5074 -25.0489 )
Norm@50keV : 1.53246E-03 ( -0.000709001 0.00556913 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.17 using 59 PHA bins.
# Reduced chi-squared = 0.9138 for 56 degrees of freedom
# Null hypothesis probability = 6.578694e-01
Photon flux (15-150 keV) in 249.2 sec: 0.160282 ( -0.020824 0.020659 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.2972e-06 ( -4.12992e-07 4.33217e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 98.636 sec. to 99.636 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30268 ( -0.512311 0.527472 )
Norm@50keV : 9.14166E-03 ( -0.00276712 0.00276312 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.04 using 59 PHA bins.
# Reduced chi-squared = 0.9481 for 57 degrees of freedom
# Null hypothesis probability = 5.867747e-01
Photon flux (15-150 keV) in 1 sec: 1.09118 ( -0.34913 0.35495 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.0288e-08 ( -2.84266e-08 2.86882e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 98.636 sec. to 99.636 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.459236 ( -1.91677 3.34615 )
Epeak [keV] : 108.508 ( -108.462 -108.462 )
Norm@50keV : 2.10634E-02 ( -0.0210787 0.293686 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.48 using 59 PHA bins.
# Reduced chi-squared = 0.9550 for 56 degrees of freedom
# Null hypothesis probability = 5.707949e-01
Photon flux (15-150 keV) in 1 sec: 1.04588 ( -0.367649 0.36974 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.1665e-08 ( 0 0 ) ergs/cm2
Time-resolved spectra
