DETECCIÓN DE UNA POBLACIÓN ESTELAR JOVEN CONTRA EL FONDO DE CÚMULOS ABIERTOS EN EL TERCER CUADRANTE DE LA GALAXIA

R.A. VÁZQUEZ, G. CARRARO, A. MOITINHO Y G. BAUME

La Plata, Buenos Aires, Argentina

Congreso; XLVIII Reunión Anual de la Asociación Argentina de Astronomía; 2005

Instituto Argentino de Radioastronomía

We report on the detection of a young stellar population (50 < age < 100 Myrs) in the background of young open clusters in the Third Galactic Quandrant that follows remarkably well the trace of the Norma-Cygnus spiral arm as defined by CO clouds. This population coincides with the one recently detected in 3 intermediate-age open clusters and suggested to be a 1-2 Gyr old population belonging to the Canis Major overdensity (Bellazzini et al. 2004). The distances and ages of the population we detected definitely rule out this possibility.