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 -7.380 sec. to 32.332 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.72166 ( -0.187183 0.182758 )
Norm@50keV : 1.82355E-03 ( -0.000195283 0.000191444 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.47 using 59 PHA bins.
# Reduced chi-squared = 0.9030 for 57 degrees of freedom
# Null hypothesis probability = 6.817514e-01
Photon flux (15-150 keV) in 39.71 sec: 0.244060 ( -0.023238 0.023281 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.69483e-07 ( -7.44789e-08 7.58151e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -7.380 sec. to 32.332 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.7298 ( -0.179992 0.208057 )
Epeak [keV] : 9999.36 ( -9999.35 -9999.36 )
Norm@50keV : 1.81538E-03 ( -0.00133417 0.00102661 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.49 using 59 PHA bins.
# Reduced chi-squared = 0.9195 for 56 degrees of freedom
# Null hypothesis probability = 6.460824e-01
Photon flux (15-150 keV) in 39.71 sec: 0.244493 ( -0.023923 0.023184 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.75912e-07 ( -8.11406e-08 6.91629e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -2.324 sec. to -1.324 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.78118 ( -0.549419 0.485416 )
Norm@50keV : 4.23754E-03 ( -0.00135546 0.00124864 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.86 using 59 PHA bins.
# Reduced chi-squared = 0.9274 for 57 degrees of freedom
# Null hypothesis probability = 6.310103e-01
Photon flux (15-150 keV) in 1 sec: 0.579747 ( -0.143394 0.143431 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.90472e-08 ( -1.20269e-08 1.26194e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.324 sec. to -1.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.14799 ( -0.0617533 1.80467 )
Epeak [keV] : 58.9638 ( )
Norm@50keV : 2.79228E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.80 using 59 PHA bins.
# Reduced chi-squared = 0.9429 for 56 degrees of freedom
# Null hypothesis probability = 5.967521e-01
Photon flux (15-150 keV) in 1 sec: 0.580834 ( -0.144253 0.142724 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.44398e-08 ( -1.52226e-08 1.12301e-08 ) ergs/cm2
Time-resolved spectra
