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arXiv · 1201.3478

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

R. Molinaro·V. Ripepi·M. Marconi·I. Musella·E. Brocato·A. Mucciarelli·P. B. Stetson·J. Storm·A. R. Walker
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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.

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R. Molinaro, V. Ripepi, M. Marconi, I. Musella, E. Brocato, A. Mucciarelli, P. B. Stetson, J. Storm, A. R. Walker. 2012-01-17. CORS Baade-Wesselink distance to the LMC NGC 1866 blue populous cluster. https://doi.org/10.1088/0004-637x/748/1/69

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