We present a method for the determination of [{alpha}/Fe] ratios from low-resolution (R=2000) SDSS/SEGUE stellar spectra. By means of a star-by-star comparison with degraded spectra from the ELODIE spectral library and with a set of moderately high-resolution (R=15000) and medium-resolution (R=6000) spectra of SDSS/SEGUE stars, we demonstrate that we are able to measure [{alpha}/Fe] from SDSS/SEGUE spectra (with S/N>20/1) to a precision of better than 0.1dex, for stars with atmospheric parameters in the range Teff=[4500,7000]K, logg=[1.5,5.0], and [Fe/H]=[-1.4,+0.3], over the range [{alpha}/Fe]=[-0.1,+0.6]. For stars with [Fe/H]25/1).

Cone search capability for table J/AJ/141/90/table1 (List of parameters for selected ELODIE spectra)

Cone search capability for table J/AJ/141/90/table2 (List of parameters for HET and ESI spectra)