Flavor changing effects in theories with a heavy Z ' boson with family nonuniversal couplings - art. no. 013006

There are theoretical and phenomenological motivations that there may exist additional heavy Z' bosons with family nonuniversal couplings. Flavor mixi ng in the quark and lepton sectors will then lead to flavor changing coupli ngs of the heavy Z', and also of the ordinary Z when Z-Z' mixing is include d. The general formalism of such effects is described, and applications are made to a variety of flavor changing and CP-violating tree and loop proces ses. Results are described for three specific cases motivated by a specific heterotic string model and by phenomenological considerations, including c ases in which all three families have different couplings, and those in whi ch the first two families, but not the third, have the same couplings. Even within a specific theory the results are model dependent because of unknow n quark and lepton mixing matrices. However, assuming that typical mixings are comparable to the Cabibbo-Kobayashi-Maskawa matrix, processes such as c oherent mu-e conversion in a muonic atom, K-0-(K) over bar(0) and B-(B) ove r bar mixing, epsilon, and epsilon'/epsilon lead to significant constraints on Z' bosons in the theoretically and phenomenologically motivated range M (Z')similar to 1 TeV.