Search for B0s-B0s oscillations and a measurement of B0d-B0d oscillations using events with an inclusively reconstructed vertex

Neutral B meson oscillations in the B0s-B0s and B0d-B0d systems were studied using a sample of about 4.0 million hadronic Z decays recorded by the DELPHI detector between 1992 and 2000. Events with a high transverse momentum lepton were removed and a sample of 770 k events with an inclusively reconstructed vertex was selected. The mass difference between the two physical states in the B0d-B0d system was measured to be: Δmd=(0.531±0.025(stat.)±0.007(syst.)) ps-1. The following limit on the width difference of these states was also obtained: vertical stroke ΔΓBd vertical stroke ΓBd<0.18 at 95% CL. As no evidence for B0s-B0s oscillations was found, a limit on the mass difference of the two physical states was given: Δms>5.0 ps-1 at 95% CL. The corresponding sensitivity of this analysis is equal to 6.6 ps-1. (orig.)