CORS Baade-Wesselink distance to the LMC NGC 1866 blue populous cluster

TL;DR

This study applies the CORS Baade-Wesselink method to determine the distance to the NGC 1866 cluster in the LMC using Cepheid variables, achieving a precise distance estimate consistent with previous measurements.

Contribution

It introduces a detailed application of the CORS Baade-Wesselink method with rigorous error analysis to measure the distance to NGC 1866.

Findings

Distance modulus of 18.51±0.03 mag for NGC 1866

Consistent with previous independent measurements

Demonstrates the effectiveness of the CORS method for distance estimation

Abstract

We used Optical, Near Infrared photometry and radial velocity data for a sample of 11 Cepheids belonging to the young LMC blue populous cluster NGC 1866 to estimate their radii and distances on the basis of the CORS Baade-Wesselink method. This technique, based on an accurate calibration of the surface brightness as a function of (U-B), (V-K) colors, allows us to estimate, simultaneously, the linear radius and the angular diameter of Cepheid variables, and consequently to derive their distance. A rigorous error estimate on radius and distances was derived by using Monte Carlo simulations. Our analysis gives a distance modulus for NGC 1866 of 18.51+/-0.03 mag, which is in agreement with several independent results.