Search for rare B meson decays into D(s)+ mesons

A search has been performed for rareB meson decays intoD s − mesons arising fromb→u transitions,W exchange modes,B+ annihilation processes, and decays where theD s + is not produced via aW→c\(\bar s\) quark pair coupling, using the ARGUS detector operating on the Ψ(4S) resonance at thee+e− storage ring DORISII. Upper limits for individual decay modes are obtained. In addition, from a study ofD s + l- correlations an upper limit of BR (B→D s + l-X) (90% CL) is determined.