Abstract
Abundances of 14 chemical elements have been derived for the two components of the double-lined AmFm spectroscopic binary o Leonis in order to set constraints on the main physical processes that lead to the Am star phenomenon.The tomographic image reconstruction and Fourier disentangling techniques were used in order to recover individual spectra from the composite spectra of the binary system observed in 9 nights using the SOPHIE spectrograph at the Observatoire de Haute Provence. Abundances have been derived by iteratively adjusting synthetic spectra to the normalized spectra of the two components by chi-squared minimization.The abundance determinations made in this paper clearly show that both components of the o Leonis binary system exhibit Am characteristics. Comparison with self-consistent evolutionary models including atomic diffusion and turbulence or mass loss shows a good agreement. This is in favor of the scenario in which element separation occurs relatively deep in the star.