Search for the U-boson in the process e +e- → μ+ μ- γ, U → μ+μ- with the KLOE detector

الأصل · EN

We present a search for a new light vector boson, carrier of a "dark force" between WIMPs, with the KLOE detector at ΦNE. We analyzed e+ e- → μ+ μ- γ ISR events corresponding to an integrated luminosity of 239 pb⁻¹ to find evidence for the e+ e- → Uγ, U→μ+μ- process. We found no U vector boson signal and set a 90% CL upper limit on the ratio of the U boson and photon coupling constants between 1.6×10⁻⁵ to 8.6×10⁻⁷ in the mass region 520<M U<980 MeV. A projection of the KLOE sensitivity for the μμγ and ππγ channels at full statistics and extended muon acceptance is also presented.