New CKM-related studies on b decays in the DELPHI experiment at LEP

The e-e+ collider LEP, running at sqrt{s} = m(Z0), has been a copious source of b-hadrons produced in decays Z0 -> b \b. We present recent studies using up to 4*10^6 hadronic Z0 decays acquired by the DELPHI detector between 1992 and 2000. They rely on efficient particle identification, precise track and vertex reconstruction and sophisticated data analysis algorithms. Presented are: a new measurement of the CKM matrix element |V_cb| in the semileptonic exclusive decays B0_d -> D*+ l- \nu_l; a new measurement of the B0_d - \B0_d oscillation frequency Delta(m_d); and searches by three methods for B0_s - \B0_s oscillations, yielding new lower limits on Delta(m_s).