New Hg-Mn binary stars in open clusters

GONZALEZ, J. F.; LEVATO, H.

Isla de Margarita

Congreso; XII Reunión Latioamericana de la IAU; 2007

Unión Astronómica Internacional

We report the discovery of three new binary systems containing Hg-Mn stars in  open clusters: NGC2546-10, NGC3532-155, and NGC6025-14. We study also the peculiar binary NGC,2287-105 previously known. In the binary system NGC2546-10 both components are HgMn stars. Besides Hg and Mn overabundance, NGC6025-14 presents strong P and Ga lines, while NGC3532-155 and NGC2287-105 present enhanced Pt and Y. We present radial velocity curves and derive  spectroscopic orbits. Their orbital periods are between 14 and 41 days and all of them are kinematic cluster members.