On the distance of the globular cluster M4 (NGC 6121) using RR Lyrae stars: I. optical and near-infrared Period-Luminosity and Period-Wesenheit relations

Abstract

We present new distance determinations to the nearby globular M4 (NGC~6121) based on accurate optical and Near Infrared (NIR) mean magnitudes for fundamental (FU) and first overtone (FO) RR Lyrae variables (RRLs), and new empirical optical and NIR Period-Luminosity (PL) and Period-Wesenheit (PW) relations. We have found that optical-NIR and NIR PL and PW relations are affected by smaller standard deviations than optical relations. The difference is the consequence of a steady decrease in the intrinsic spread of cluster RRL apparent magnitudes at fixed period as longer wavelengths are considered. The weighted mean visual apparent magnitude of 44 cluster RRLs is $⟨V⟩=13.329\pm 0.001$ (standard error of the mean) $\pm$0.177 (weighted standard deviation) mag. Distances were estimated using RR Lyr itself to fix the zero-point of the empirical PL and PW relations. Using the entire sample (FU$+$FO) we found weighted mean true distance moduli of 11.35$\pm$0.03$\pm$0.05 mag and 11.32$\pm$0.02$\pm$0.07 mag. Distances were also evaluated using predicted metallicity dependent PLZ and PWZ relations. We found weighted mean true distance moduli of 11.283$\pm$0.010$\pm$0.018 mag (NIR PLZ) and 11.272$\pm$0.005$\pm$0.019 mag (optical--NIR and NIR PWZ). The above weighted mean true distance moduli agree within 1$\sigma$. The same result is found from distances based on PWZ relations in which the color index is independent of the adopted magnitude (11.272$\pm$0.004$\pm$0.013 mag). These distances agree quite well with the geometric distance provided by \citep{kaluzny2013} based on three eclipsing binaries. The available evidence indicates that this approach can provide distances to globulars hosting RRLs with a precision better than 2--3\%.

Accepted for publication on ApJ

References in corpus (15)

• The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous HST Photometry
• Updated Electron-Conduction Opacities: The Impact on Low-Mass Stellar Models
• Spectroscopic and Photometric evidence of two stellar populations in the Galactic Globular Cluster NGC6121 (M4)
• HD 140283: A Star in the Solar Neighborhood that Formed Shortly After the Big Bang
• The RR Lyrae Period - K Luminosity relation for Globular Clusters: an observational approach
• Optical and Near-Infrared UBVRIJHK Photometry for the RR Lyrae stars in the Nearby Globular Cluster M4 (NGC 6121)
• On the distance of the Magellanic Clouds using Cepheid NIR and optical-NIR Period Wesenheit Relations
• Space Velocities of Southern Globular Clusters. V. A Low Galactic Latitude Sample
• Cepheids in external galaxies. I. The maser-host galaxy NGC 4258 and the metallicity dependence of P-L and P-W relations
• Merging of globular clusters within inner galactic regions. II. The Nuclear Star Cluster formation
• The infrared JHK light curves of RR Lyr
• Relative distances of Omega Centauri and 47 Tucanae
• Proper Motions in the Galactic Bulge: Plaut's Window
• Multicolour CCD photometry of the variable stars in globular cluster M3
• The Araucaria Project. The Distance to the Sculptor Group Galaxy NGC 55 from a Newly Discovered Abundant Cepheid Population

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