The Distance to the Large Magellanic Cloud Cluster Reticulum from the K ‐Band Period‐Luminosity‐Metallicity Relation of RR Lyrae Stars

Abstract

We present new and accurate near-infrared J- and Ks-band data of the Large Magellanic Cloud cluster Reticulum. Data were collected with SOFI at the New Technology Telescope and covered an area of approximately 5′ × 5× around the center of the cluster. Current data allowed us to derive accurate mean K-bana magnitudes for 21 fundamental (RRab) and 9 first-overtone (RRc) RR Lyrae stars. On the basis of the semiempirical K-band period-luminosity-metallicity (PLZK) relation we have recently derived, we find that the absolute distance to this cluster is 18.52 ± 0.005 (random) ± 0.117 (systematic). Note that the current error budget is dominated by systematic uncertainty affecting the absolute zero-point calibration and the metallicity scale.