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 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 radii and distances was derived by using Monte Carlo simulations. Our analysis gives a distance modulus for NGC 1866 of 18.51 ± 0.03mag, which is in agreement with several independent results.
R. Molinaro, V. Ripepi, M. Marconi, I. Musella, E. Brocato, A. Mucciarelli, et al. (2012). CORS BAADE–WESSELINK DISTANCE TO THE LMC NGC 1866 BLUE POPULOUS CLUSTER. THE ASTROPHYSICAL JOURNAL, 748, 69-82 [10.1088/0004-637X/748/1/69].
CORS BAADE–WESSELINK DISTANCE TO THE LMC NGC 1866 BLUE POPULOUS CLUSTER
MUCCIARELLI, ALESSIO;
2012
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 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 radii and distances was derived by using Monte Carlo simulations. Our analysis gives a distance modulus for NGC 1866 of 18.51 ± 0.03mag, which is in agreement with several independent results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
