RADIATIVE-CORRECTIONS TO PI(12) DECAYS

Radiative corrections to pi(l2) (l = e or mu) decays are examined. Hig her order electroweak leading logarithms, short-distance QCD correctio ns, and structure dependent effects are incorporated. The results are employed to (1) test e-mu universality in GAMMA(pi --> enu(e)BAR(gamma ))/GAMMA(pi --> munu(mu)BAR(gamma)), (2) extract an f(pi) which is use d to check the Goldberger-Treiman relation and PCAC-anomaly prediction for GAMMA(pi0 --> gammagamma), and (3) determine the tau partial deca y rate GAMMA(tau --> pinu(tau)(gamma)).