2011MNRAS.411.2311F

The Bochum Échelle Spectroscopic Observer BESO is a fibre-fed high-resolution spectrograph for the 1.5-m Hexapod Telescope at the Cerro Armazones Observatory in the Atacama desert in Chile. Here we report on the first BESO observations and model atmosphere analyses of solar-type stars secured in 2010 April. The quality of the data is first tested with a reflected sunlight spectrum as well as the standard G-type subgiant 70 Vir. We then investigate the bright and supposedly single F-type star ξ Gem and present the spectroscopic evidence that instead favours an equal-mass binary. We present also the first composite synthetic modelling of the G-type visual binary HR 3430 and discuss the spectroscopic observations that identify this as a triple system. We conclude with another triple, the famous and very nearby α Cen, and the basic stellar parameters of its inner, solar-type visual binary.