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 -8.600 sec. to 45.464 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.17207 ( -0.127129 0.129368 )
Norm@50keV : 4.71694E-03 ( -0.000329096 0.000328006 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.96 using 59 PHA bins.
# Reduced chi-squared = 1.105 for 57 degrees of freedom
# Null hypothesis probability = 2.735888e-01
Photon flux (15-150 keV) in 54.06 sec: 0.551597 ( -0.040579 0.040811 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.60817e-06 ( -1.92679e-07 1.9349e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -8.600 sec. to 45.464 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.16741 ( -0.183282 0.261347 )
Epeak [keV] : 9999.28 ( -9999.3 -9999.3 )
Norm@50keV : 4.74032E-03 ( -0.000326708 0.00147269 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.00 using 59 PHA bins.
# Reduced chi-squared = 1.125 for 56 degrees of freedom
# Null hypothesis probability = 2.426089e-01
Photon flux (15-150 keV) in 54.06 sec: 0.551486 ( -0.040656 0.04075 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.61762e-06 ( -2.6925e-07 2.56179e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.060 sec. to 1.060 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.765962 ( -0.262469 0.278545 )
Norm@50keV : 2.01904E-02 ( -0.00318586 0.00311517 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.73 using 59 PHA bins.
# Reduced chi-squared = 0.8198 for 57 degrees of freedom
# Null hypothesis probability = 8.322653e-01
Photon flux (15-150 keV) in 1 sec: 2.32388 ( -0.35068 0.35224 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.39409e-07 ( -3.71863e-08 3.73107e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.060 sec. to 1.060 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.758009 ( -0.285331 1.16153 )
Epeak [keV] : 10000.00 ( -10000 -10000 )
Norm@50keV : 2.03393E-02 ( -0.00319978 0.00294086 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.73 using 59 PHA bins.
# Reduced chi-squared = 0.8344 for 56 degrees of freedom
# Null hypothesis probability = 8.066777e-01
Photon flux (15-150 keV) in 1 sec: 2.32233 ( -0.35847 0.35287 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.39343e-07 ( -3.75575e-08 3.563e-08 ) ergs/cm2
Time-resolved spectra
