SEARCH FOR η_b AT CDF

摘要

The η_b(1S) is the J_(PC) = 0~(+-)bb-bar ground state, and has not yet been experimentally observed. Theorists have recently suggested that it could be observed at the Fermilab Tevatron through its decay to J/ψJ/ψ, if not in the 1992-96 ("Run 1") dataset, then in Run 2. This article describes a search for this particle at CDF in Run 1 using this decay channel. A small cluster is seen, with 7 events where 1.8 events are expected from background. The statistical significance is estimated to be 2.2σ, and an upper limit is set on the product of cross section and branching fractions.