CU Comae: a new field double-mode RR Lyrae, the most metal poor discovered to date

G. Clementini, S. Di Tomaso, L. Di Fabrizio +12

We report the discovery of a new double-mode RR Lyrae variable (RRd) in the field of our Galaxy: CU Comae. CU Comae is the sixth such RRd identified to date and is the most metal-p…