33 RR Lyrae observed in Pisces with K2-E2 Universiteit Antwerpen
Katrien Kolenberg, L. Molnar, Z. Kollath, R. Szabo, P.A. Moskalik, J.M. Nemec, E. Guggenberger, R. Smolec, R. Poleski, E. Plachy
A detailed analysis is presented of 33 RR Lyrae stars in Pisces observed with the Kepler space telescope over the 8.9-d long K2 Two-Wheel Concept Engineering Test. The sample includes not only fundamental-mode and first-overtone (RRab and RRc) stars but the first two double-mode (RRd) stars that Kepler detected and the only modulated first-overtone star ever observed from space so far. The precision of the extracted K2 light curves made it possible to detect low-amplitude additional modes in all subtypes. All RRd and non-modulated RRc stars show the additional mode at PX/P1∼0.61 that was ...