![Sample spectral regions in the optical (blue chip, top), and infrared (bottom) showing magnesium, scandium, and iron lines that were used in the abundance analysis.[]{data-label="fig:mgspectra"}](irspectra.pdf "fig:"){width="50.00000%"}

Equivalent Width Analysis of Optical Spectra
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Optical abundances are determined from an equivalent width (EW) analysis. All equivalent widths were initially measured using DAOSPEC [@b1][^8]. The atomic lines used with DAOSPEC are comprised of a list taken from several sources: @b13, @b14, @b15, @b16, @b17, @b18, @b19, and @b77. ; the IRAF measurements were adopted for lines $>$ 100 mÅ. Lines were also examined by eye for unrecognized blends or other mismeasurements (i.e. contaminated with noise spikes, etc.), using the spectrum of Arcturus and the Sun as references. Lines with EWs $>$ 200 mÅ were not analysed since they tend to be very sensitive to small uncertainties in

$\Delta EW$
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The uncertainty in EW measurements can be estimated from the revised Cayrel formula [@b78; @b11],

$$\Delta (EW) \sim \frac{\sqrt{1.5 \cdot FWHM \cdot \Delta x}}{S/N}$$

where FWHM is the measured full width at half maximum of a particular line in Å, $\Delta$ x is the dispersion of the spectra in Å/pixel (37.9 mÅ for the Blue chip and 50.89 mÅ for the Red), 