of a simple polynomial relationship between microturbulence velocity and surface gravity, $\xi_{t}$ \[km s$^{-1}$\] = $-0.345\cdot $log $g+2.225$, derived from the high-resolution spectra of SDSS/SEGUE stars used to calibrate the SSPP. The synthetic spectra have wavelength steps of 0.01 Å, covering the wavelength range 4000–5000 Å, which includes the CH $G$-band ($\sim$4300 Å), as well as lines of Sr[ii]{} ($\sim$4077 Å) and Ba[ii]{} ($\sim$4554 Å).

The final grid covers 4000 K $\leq T_{\rm eff} \leq$ 7000 K in steps of 250 K, 1.0 $\leq \log~g \leq $ 5.0 in steps of 0.5 dex, and $-4.0 \leq
\rm [Fe/H] \leq +0.5$ in steps of 0.25 dex. The range of [\[C/Fe\]]{} varies with the metallicity in steps of 0.25 dex as follows:

-   $-0.5 \leq$ \[C/Fe\] $\leq +3.5$ for \[Fe/H\] $\leq -1.25$

-   $-0.5 \leq$ \[C/Fe\] $\leq +1.5$ for $-1.25 <$ \[Fe/H\] $\leq -0.75$

-   $-0.5 \leq$ \[C/Fe\] $\leq +1.0$ for \[Fe/H\] $> -0.75$

The total number of generated synthetic spectra is 30,069. Once created, the full set of synthetic spectra are degraded to SDSS resolution ($R=2000$), and re-sampled to 1 Å wide linear pixels over the wavelength 4000–4650 Å. Each degraded grid is normalized by division with a pseudo continuum, obtained 