New Hg-Mn binary stars in open clusters

GONZALEZ, J. F.; LEVATO, H.

Isla de Margarita, Venezuela

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 themare kinematic cluster members.