Near-threshold Photoproduction of Phi Mesons from Deuterium

Abstract

We report the first measurement of the differential cross section on $\ddot{I}•$-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, $K^{+}$ and $K^{-}$ near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections $\frac{d\ddot{I}ƒ}{dt}$ for the initial photon energy from 1.65-1.75 GeV are consistent with predictions based on a quasifree mechanism. This experiment establishes a baseline for a future experimental search for an exotic $\ddot{I}•$-N bound state from heavier nuclear targets utilizing subthreshold/near-threshold production of $\ddot{I}•$ mesons.