γZ kinetic mixing as signal of a higher scale

In models with an additional large scale the low-energy effective Lagrangian may contain terms beyond the standard model which generate kinetic mixing between the γ and Z. This modifies the coupling of the Z and changes the relation between the masses of the W,Z and the parameters α/sub EM/, G/sub F/, and sintheta/sub W/2. Such an effect, which probes the existence of a higher scale (compositeness, extended hypercolor, etc.) may be seen in future precision measurements of the W,Z masses and Z couplings