B, V, I photometry of the complete sample of 23 Cepheids in the field of NGC 1866

Abstract

We present the result of BVI photometry, obtained by using FORS@VLT, of the Cepheids present in the field of the Large Magellanic Cloud cluster NGC 1866. We found the 22 known variables plus an additional new Cepheid located about 10' from the cluster center. The accuracy of the photometry allowed us to derive B, V and I mean magnitudes with an uncertainty lower than 0.02 mag for 22 out of the 23 objects, with the exception of only one Cepheid (WS9) which presents a noisy light curve due to the probable occurrence of image blending. As a result, we provide accurate observational data for a substantial sample of variables all lying at the same distance and with a common original composition. The resulting period-luminosity relations are presented and briefly discussed.Comment: 4 pages, 6 figure, to appear in the proceedings of the Workshop "Stellar pulsation and evolution", 2005. Monte Porzio Catone, Italy. Eds.: A. R. Walker and G. Bon