Search for New Vector Bosons and a Test of Quantum Electrodynamics

Muon pairs with invariant pair mass M_μμ between 1300 and 2100 MeV have been photoproduced from carbon. No evidence is found for a heavy vector boson decaying into muon pairs in this mass region, and upper limits on its production are given. Limits on a possible breakdown of quantum electrodynamics are also obtained. Assuming a breakdown in the cross section proportional to M_μμ⁴, we obtain an upper limit on the breakdown parameter λ of |λ|<0.035 GeV^-4, with a confidence level of 95%.