  Numerous non-standard dynamics are described by contact-like effective
interactions that can manifest themselves in electron-positron collisions only
through deviations of the observables (cross sections, asymmetries) from the
Standard Model predictions. If such a deviation were observed, it would be
important to identify the actual source among the possible non-standard
interactions as many different new physics scenarios may lead to very similar
experimental signatures. We study the possibility of uniquely identifying the
indirect effects of s-channel sneutrino exchange, as predicted by
supersymmetric theories with R-parity violation, against other new physics
scenarios in high-energy e^+e^- annihilation into lepton pairs at the
International Linear Collider. These competitive models are interactions based
on gravity in large and in TeV-scale extra dimensions, anomalous gauge
couplings, Z' vector bosons and compositeness-inspired four-fermion contact
interactions. To evaluate the identification reach on sneutrino exchange, we
use as basic observable a double polarization asymmetry, that is particularly
suitable to directly test for such s-channel sneutrino exchange effects in the
data analysis. The availability of both beams being polarized plays a crucial
role in identifying the new physics scenario.
