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 -206.480 sec. to 341.552 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.61867 ( -0.10657 0.105697 )
Norm@50keV : 1.90910E-03 ( -0.000112469 0.000111916 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.33 using 59 PHA bins.
# Reduced chi-squared = 0.7778 for 57 degrees of freedom
# Null hypothesis probability = 8.895547e-01
Photon flux (15-150 keV) in 548 sec: 0.246776 ( -0.014475 0.014512 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.76383e-06 ( -6.15311e-07 6.19596e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -206.480 sec. to 341.552 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.61978 ( -0.10545 0.108336 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 1.90717E-03 ( -0.000345459 0.000885329 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.34 using 59 PHA bins.
# Reduced chi-squared = 0.7919 for 56 degrees of freedom
# Null hypothesis probability = 8.695895e-01
Photon flux (15-150 keV) in 548 sec: 0.247419 ( -0.017141 0.01528 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.79402e-06 ( -7.10159e-07 5.00605e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 151.572 sec. to 152.572 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.9173 ( -0.446182 0.386008 )
Norm@50keV : 8.86763E-03 ( -0.00275317 0.002649 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.17 using 59 PHA bins.
# Reduced chi-squared = 1.284 for 57 degrees of freedom
# Null hypothesis probability = 7.320159e-02
Photon flux (15-150 keV) in 1 sec: 1.28213 ( -0.324947 0.32498 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.15511e-08 ( -2.39846e-08 2.47824e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 151.572 sec. to 152.572 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.428527 ( -1.56307 2.42453 )
Epeak [keV] : 47.8596 ( )
Norm@50keV : 5.91427E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.53 using 59 PHA bins.
# Reduced chi-squared = 1.259 for 56 degrees of freedom
# Null hypothesis probability = 9.157560e-02
Photon flux (15-150 keV) in 1 sec: 1.26699 ( -0.323326 0.32398 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.7707e-08 ( -2.30948e-08 2.48724e-08 ) ergs/cm2
Time-resolved spectra
