Near-threshold Photoproduction of Phi Mesons from Deuterium

TL;DR

This study measures the differential cross section of phi meson photoproduction from deuterium near the threshold energy, providing baseline data for future searches for exotic phi-N bound states.

Contribution

First measurement of phi meson photoproduction cross sections near threshold from deuterium, supporting quasifree production models and enabling future exotic state searches.

Findings

Differential cross sections align with quasifree mechanism predictions.

Measurement conducted near the production threshold of 1.57 GeV.

Establishes baseline for future heavy nuclear target experiments.

Abstract

We report the first measurement of the differential cross section on $\phi$-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 $\frac{d\sigma}{dt}$ 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 $\phi$-N bound state from heavier nuclear targets utilizing subthreshold/near-threshold production of $\phi$ mesons.