Deeply Virtual Pseudoscalar Meson Production at Jefferson Lab and Transversity GPDs

Abstract

The cross section of the exclusive ${\pi }^0$ and $\eta$ electroproduction reaction $ep\to e^{\prime }{p}^{\prime }{\pi }^0/\eta$ was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections $d^4\sigma /dtd{Q}^{2}d{x}_{B}d\varphi$ and structure functions ${\sigma }_T+\epsilon {\sigma }_L,{\sigma }_{TT}$ and ${\sigma }_{LT}$ as functions of $t$ were obtained over a wide range of $Q^2$ and $x_B$. The data are compared with the GPD based theoretical models. Analyses find that a large dominance of transverse processes is necessary to explain the experimental results. Generalized form factors of the transversity GPDs $H_T^{\pi ,\eta }$ and ${\bar{E}}_T^{\pi ,\eta }$ were directly extracted from the experimental observables for the first time. It was found that GPD ${\bar{E}}_T$ dominates in pseudoscalar meson production. The combined ${\pi }^0$ and $\eta$ data opens the way for the flavor decomposition of the transversity GPDs. The first ever evaluation of this decomposition was demonstrated.

6 pages, 5 figures, Invited talk paper compiled for the SPIN-2014 conference proceedings. Typos corrected

References in corpus (3)

• Nucleon Tensor Charge from Exclusive ${\pi }^o$ Electroproduction
• Measurement of Exclusive ${\pi }^0$ Electroproduction Structure Functions and their Relationship to Transversity GPDs
• Exclusive ${\pi }^0$ electroproduction at $W>2$ GeV with CLAS

Cited by in corpus (4)

• Spatial imaging of proton via leading-twist non-skewed GPDs with basis light-front quantization
• Spin-flavor structure of chiral-odd GPDs in the large-N_c limit
• Study of transversity GPDs from pseudoscalar mesons production at EIC of China
• The exclusive Drell-Yan process and deeply virtual pion production