On the Use of Field RR Lyrae as Galactic Probes. III. The $\alpha$-element abundances

J. Crestani, V. F. Braga, M. Fabrizio +33

We provide the largest and most homogeneous sample of $\alpha$-element (Mg, Ca, Ti) and iron abundances for field RR Lyrae (RRLs, 162 variables) by using high-resolution spectra. The cu…