Study of 3-prong hadronic τ decays with charged kaons

Using a sample of 4.7 fb{sup -1} integrated luminosity accumulated with the CLEO-II detector at the Cornell Electron Storage Ring (CESR), we have measured the ratios of the branching fractions B({tau}{sup -}{yields}K{sup -}h{sup +}{pi}{sup -}{nu}{sub {tau}})/B({tau}{sup -}{yields}h{sup -}h{sup +}h{sup -}{nu}{sub {tau}})=(5.16(+= - )0.20{+-}0.50)x10{sup -2}, B({tau}{sup -}{yields}K{sup -}h{sup +}{pi}{sup -}{pi}{sup 0}{nu}{sub {tau}})/B({tau}{sup -}{yields}h{sup -}h{sup +}h{sup -}{pi}{sup 0}{nu}{sub (t= a u))=(2.54{+-}0.44{+-}0.39)x10{sup -2}, B({tau}{sup -}{yields}K{sup -}K{sup +}{pi}{sup -}{nu}{sub {tau}})/B({tau}{sup -}{yields}h{sup -}h{sup +}h{sup -}{nu}{sub {tau}})=(1.52(+= - )0.14{+-}0.29)x10{sup -2}, and the upper limit B({tau}{sup -}{yields}K{sup -}K{sup +}{pi}{sup -}{pi}{sup 0}{nu}{sub {tau}})/B({tau}{sup -}{yields}h{sup -}h{sup +}h{sup -}{pi}{sup 0}{nu}{sub (t= a u))<0.0154 at 95% C.L. Coupled with additional experimental information, we use our results to extract information on the structure of three-prong tau decays to charged kaons. (c) 1999 The American Physical Society.