BOSE-EINSTEIN AND COLOR INTERFERENCE IN W-PAIR DECAYS

We study effects on the W mass measurements at LEP2 from non-perturbat ive interference effects in the fully hadronic decay channel. Based on a model for Bose-Einstein interference, which is in agreement with LE P1 data, we argue that there are no Bose-Einstein correlations between bosons coming from the different W's. For small reconnection probabil ities we rule out the possible experimental signal of colour interfere nce at LEP2, suggested in [1]. The conclusions from this paper are tha t the theoretical uncertainties in the W mass determination should be smaller than the experimental statistical error.