Search for Lambda(+)(c)-> pK(+)pi(-) and D-s(+)-> K+K+pi(-) using genetic programming event selection

We apply a genetic programming technique to search for the doubly Cabibbo suppressed decays Λ+c → pK+π− and Ds+ → K+K+π−. We normalize these decays to their Cabibbo favored partners and find BR(Λ+c → pK+π−)/BR(Λ+c → pK−π+) = (0.05 ± 0.26 ± 0.02)% and BR(Ds+ → K+K+π−)/BR(Ds+ → 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 < 0.46 and < 0.78%, respectively. This is the first successful use of genetic programming in a high energy physics data analysis.