dex, and 0.23 dex, respectively (Smolinski et al. 2011), most reliably for stars in the temperature range 4500 K $<$ [$T_{\rm eff}$]{} $<$ 7500 K. As described by Lee et al. (2011), the SSPP can also obtain an estimate of [\[$\alpha$/Fe\]]{}, with a precision of better than 0.1 dex, for SDSS/SEGUE spectra having S/N $\geq 20$ Å$^{-1}$.

A New Grid of Synthetic Spectra for Determination of [\[C/Fe\]]{}
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Since it is not practical to analyze hundreds of thousands of stellar spectra one at a time, we have modified the SSPP so that it is capable of estimating \[C/Fe\] in a fast, efficient manner. To accomplish this, we introduce a pre-existing grid of synthetic spectra. This eliminates the need for generating synthetic spectra on the fly, while simultaneously attempting to determine the primary atmospheric parameters and/or other elemental abundances.

As emphasized in Masseron (2006), carbon enhancement affects the thermodynamical structure of stellar atmospheres. To take into account this effect, specific models have been tailored with various carbon abundances using the MARCS code (Gustafsson et al. 2008). From those models, we have created synthetic spectra using the [Turbospectrum]{} synthesis code (Alvarez & Plez 1998; Plez 2012), which employs the line broadening treatment 