Measuring the a₂^-(1320) Photoproduction Cross-Section using the KKbar Decay Mode at GlueX.

The GlueX experiment at Jefferson Lab studies photoproduction reactions using a linearly polarized photon beam of up to 12 GeV in an effort to identify light hybrid mesons. Current hybrid meson searches at GlueX include exclusive reconstruction of the γp → ηπ Δ⁺⁺ reaction. To distinguish the overlapping contributions to the ηπ^- system and search for a contribution of the spin-exotic π₁(1600), we focus on understanding the production of the a₂(1320). The light meson is a dominant contribution in the ηπ system in the exotics mass range and an important reference point. In this contribution we will present a complementary study of a₂^- production yield using the exclusive reconstruction of the reaction γp → K_S K^- π⁺ p. The status of the differential photoproduction cross section as a function of four-momentum transfer squared t will be presented. As a consequence, the full -t and beam energy range can be used to measure a more precise B(a₂→ KKbar)/B(a₂ →ηπ) branching fraction using GlueX data.