The 59th Winter Nuclear & Particle Physics Conference (WNPPC2022)

η Meson Photoproduction with the GlueX Experiment

17 Feb 2022, 10:48

12m

virtual

QCD and Hadrons Scattering and Electrons

Speaker

Jonathan Zarling (University of Regina)

Description

Studies of the exclusive production of the $\eta$ meson in photonuclear reactions offer a wide range of physics insight. These include constraining models of hadron photoproduction, insight into the spectrum of excited N* states, and may even provide a probe into the structure of the nucleon at wide-angles of production. GlueX, a high-intensity photoproduction experiment located at Hall D of Jefferson Lab, measures exclusive $\eta$ mesons off the proton with large statistics and comparatively low background. We present cross section measurements of $\eta$ photoproduction at $E_{\gamma }=$ 6-11 GeV and find consistent results using the decay modes $\eta \to \gamma \gamma$, ${\pi }^{+}{\pi }^{-}{\pi }^0$, and ${\pi }^0{\pi }^0{\pi }^0$. When studied as a function of Mandelstam $t$, these cross sections can constrain models describing $\eta$ production in terms of $t$-channel Reggeon exchange. Such measurements inform future searches for exotic hybrid mesons and serve as a benchmark for the Jefferson Lab Eta Factory, a future upgrade to the existing GlueX facility focused on rare $\eta$ decays.

This work is supported by the Natural Sciences and Engineering Research Council of Canada Grant No. SAPPJ-2018-00021.

Presentation materials

eta_xsec.pdf