Period-luminosity and period-luminosity-metallicity relations for Galactic RR Lyrae stars in the Sloan bands

Abstract

RR Lyrae stars are excellent tracers of the old population II due to their period-luminosity (PL) and period-luminosity-metallicity (PLZ) relations. While these relations have been investigated in detail in many photometric bands, there are few comprehensive studies about them in Sloan-like systems. We present PL and PLZ relations (as well as their counterparts in Wesenheit magnitudes) in the Sloan--Pan-STARSS $g_ P1 r_ P1 i_ P1 $ bands obtained for Galactic RR Lyrae stars in the vincinity of the Sun. The data used in this paper were collected with the network of $40$ cm telescopes of the Las Cumbres Observatory, and geometric parallaxes were adopted from Gaia Data Release $3$. We derived PL and PLZ relations separately for RRab and RRc-type stars, as well as for the mixed population of RRab+RRc stars. To our knowledge, these are the first PL and PLZ relations in the Sloan bands determined using RR Lyrae stars in the Galactic field.