CAN LIGHT NAMBU-GOLDSTONE BOSON LOOPS COUNTER THE S-ARGUMENT AGAINST TECHNICOLOR

We examine the oblique correction phenomenology of one-family technico lor with light pseudo Nambu-Goldstone bosons. From loop calculations b ased on a gauged chiral Lagrangian for technicolor we are led to concl ude that even though loops with light Nambu-Goldstone bosons give a ne gative contribution to S measured at the Z pole, this effect is not su fficiently large to unambiguously counter the ''S argument'' against o ne-family technicolor. This result cannot be guessed a priori, but mus t be explicitly calculated. Our analysis entails an extended version o f the STU oblique parametrization of Peskin and Takeuchi. In principle , this extended formalism (STUVWX) must be used when there are light n ew particles in loops.