Cosmological Parameter Uncertainties from SALT-II Type Ia Supernova
  Light Curve Models
  We use simulated SN Ia samples, including both photometry and spectra, to
perform the first direct validation of cosmology analysis using the SALT-II
light curve model. This validation includes residuals from the light curve
training process, systematic biases in SN Ia distance measurements, and the
bias on the dark energy equation of state parameter w. Using the SN-analysis
package SNANA, we simulate and analyze realistic samples corresponding to the
data samples used in the SNLS3 analysis: 120 low-redshift (z < 0.1) SNe Ia, 255
SDSS SNe Ia (z < 0.4), and 290 SNLS SNe Ia (z <= 1). To probe systematic
uncertainties in detail, we vary the input spectral model, the model of
intrinsic scatter, and the smoothing (i.e., regularization) parameters used
during the SALT-II model training. Using realistic intrinsic scatter models
results in a slight bias in the ultraviolet portion of the trained SALT-II
model, and w biases (winput - wrecovered) ranging from -0.005 +/- 0.012 to
-0.024 +/- 0.010. These biases are indistinguishable from each other within
uncertainty; the average bias on w is -0.014 +/- 0.007.
