Classical Cepheids, what else?

TL;DR

This paper refines distance estimates to the Magellanic Clouds using near-infrared and optical-NIR period-Wesenheit relations for Cepheids, confirming their reliability and consistency with other methods.

Contribution

It provides new independent distance measurements to the Magellanic Clouds using NIR and optical-NIR PW relations, with zero points fixed from Galactic Cepheids.

Findings

Distances to LMC and SMC are consistent with previous estimates.

PW relations are linear and metal-independent over the entire period range.

Zero points fixed using Galactic Cepheids yield accurate distance moduli.

Abstract

We present new and independent estimates of the distances to the Magellanic Clouds (MCs) using near-infrared (NIR) and optical--NIR period--Wesenheit (PW) relations. The slopes of the PW relations are, within the dispersion, linear over the entire period range and independent of metal content. The absolute zero points were fixed using Galactic Cepheids with distances based on the infrared surface-brightness method. The true distance modulus we found for the Large Magellanic Cloud---$(m-M)_0 = 18.48 \pm 0.01 \pm 0.10$ mag---and the Small Magellanic Cloud---$(m-M)_0 = 18.94 \pm 0.01 \pm 0.10$ mag---agree quite well with similar distance determinations based on robust distance indicators. We also briefly discuss the evolutionary and pulsation properties of MC Cepheids.