MODEL-INDEPENDENT LIMITS ON 4-FERMION CONTACT INTERACTIONS AT LC WITHPOLARIZATION

Fermion compositeness, and other types of new physics that can be desc ribed by the exchange of very massive particles, can manifest themselv es as the result of an effective four-ferrnion contact interaction. In the case of the processes e(+) e(-)-->mu(+)mu(-),tau(+)tau(-), (b) ov er bar b and (c) over bar c at future e(+)e(-) colliders with root s = 0.5-1 TeV, we examine the sensitivity to four-fermion contact interac tions of two new integrated observables, sigma(+), and sigma(-), conve niently defined for such kind of analysis. We find that, if longitudin al polarization of the electron beam were available, these observables would offer the opportunity to separate the helicity cross sections a nd, in this way, to derive model-independent bounds on the relevant pa rameters. (C) 1998 Published by Elsevier Science B.V. All rights reser ved.