The rare decay K+->pi(+)-nu(nu)over-bar and effects of charged technipions

In this paper we calculate the contributions to the FCNC rare decay K+ --> pi(+)<nu(nu)over bar> from the charged technipion P+/- and P-8(+/-) in the framework of technicolor theory. We find that: (a) P+/- can provide a posit ive but relatively small contribution to the K+ --> pi(+)<nu(nu)over bar> p rocess; (b) the contribution is large and positive for relatively light P-8 (+/-) and becomes negative for m(p8) greater than or equal to 531 GeV; (c) the enhancement to the ratio BR(K+ --> pi(+)<nu(nu)over bar>) can be as lar ge as a factor of 30 for m(p1) = 50 GeV and m(p8) = 100 GeV; (d) the lower mass bound on m(p8) is m(p8) > 220, 190 GeV for m(p1) = 50, 200 GeV, respec tively.