Speaker
Dr
Zhenyu ZHANG
(Wuhan University)
Description
The high-energy photoproduction of light-quark pseudoscalar and scalar mesons is an effective tool for understanding the properties of strong interaction in the nonperturbative regime. It has been investigated theoretically using Regge-cut phenomenology with massive quasi-particle exchange in high-energy regime, and the linearly polarized photon beam asymmetry $\Sigma$ can provide insight into dominant production mechanism. In the low-energy region, it can provide constraints on "background" to baryon resonance extraction. With almost 50-year history, intensive experiments on meson photoproduction are growing vigorously at several international laboratories, such as JLab, ELSA, and MAMI. Recently the beam asymmetry $\Sigma$ in high-energy $\pi^0/\eta$ photoproduction has been measured at GlueX, which is the first measurement both from the GlueX experiment and the 12-GeV-upgraded JLab. The highest precision measurement of the $\pi^0$ asymmetry and the first measurement of $\eta$ beam asymmetry at the energy above $E_{\gamma} = 3$ GeV are presented. A broad meson photoproduction project, including scalar meson $a_0(980) /f_0(980)$, is under way at GlueX. In this talk, we will report the beam asymmetry results for $\pi^0/\eta$ photoproduction at GlueX, as well as preliminary results for scalar meson photoproduction in the $\pi^0 \pi^0$ and $\pi^0 \eta$ channels.
Primary author
Dr
Zhenyu ZHANG
(Wuhan University)
