Supersymmetry tests from a combined analysis of a chargino and charged Higgs boson pair production at a 1 TeV linear collider

We consider the production of chargino and charged Higgs boson pairs at future linear colliders for c.m. energies in the one TeV range. Working in the MSSM under the assumption of a "moderately" light SUSY scenario, we compute the leading (double) and next-to-leading (linear) supersymmetric logarithmic terms of the so-called "Sudakov expansion" at one loop. We show that a combined analysis of the slopes of the chargino and of the charged Higgs production cross sections would offer a simple possibility for determining tan beta for large (greater than or similar to10) values and an allowed strip in the (M-2,mu) plane. This could provide a strong consistency test of the considered supersymmetric model.