VMC RR Lyrae in LMC

For these objects, near-infrared time-series photometry from the VISTA survey of the Magellanic Clouds system (VMC) and optical data from the Optical Gravitational Lensing Experiment (OGLE) IV survey and the Gaia Data Release 2 catalogue of confirmed RR Lyrae stars were exploited. Using VMC and OGLE IV magnitudes we derived period-luminosity (PL), period-luminosity-metallicity (PLZ), period-Wesenheit (PW), and period-Wesenheit-metallicity (PWZ) relations in all available bands.

More that 7000 RR Lyrae were discarded from the analysis because they appear to be overluminous with respect to the PL relations. The PL_K_s_ relation was used to derive individual distance to ~22000 RR Lyrae stars, and study the three-dimensional structure of the LMC. The distribution of the LMC RR Lyrae stars is ellipsoidal with the three axis S_1_=6.5kpc, S_2_=4.6kpc, and S_3_=3.7kpc, inclination i=22+/-4{deg} relative to the plane of the sky and position angle of the line of nodes {theta}=167+/-7{deg} (measured from north to east).