Search for Λc+→pK+π− and Ds+→K+K+π− using genetic programming event selection

Abstract We apply a genetic programming technique to search for the doubly Cabibbo suppressed decays Λ c + → p K + π − and D s + → K + K + π − . We normalize these decays to their Cabibbo favored partners and find BR ( Λ c + → p K + π − ) / BR ( Λ c + → p K − π + ) = ( 0.05 ± 0.26 ± 0.02 ) % and BR ( D s + → K + K + π − ) / BR ( D s + → K − K + π + ) = ( 0.52 ± 0.17 ± 0.11 ) % where the first errors are statistical and the second are systematic. Expressed as 90% confidence levels (CL), we find