# Exclusive $\eta$ electroproduction at $W>2$ GeV with CLAS and transversity generalized parton distributions

## TL;DR

This paper reports on measurements of exclusive eta electroproduction at high energies using CLAS, providing insights into transversity GPDs and their flavor decomposition, with results consistent with theoretical models at low momentum transfer.

## Contribution

It presents new experimental data on eta electroproduction at W>2 GeV, comparing it with pi0 data to enhance understanding of transversity GPDs and their flavor structure.

## Key findings

- Cross sections and structure functions measured over wide Q^2 and x_B ranges.
- Data consistent with chiral-odd transversity GPD dominance at low t.
- Combined eta and pi0 data aid in flavor decomposition of transversity GPDs.

## Abstract

The cross section of the exclusive $\eta$ electroproduction reaction $ep\to e^\prime p^\prime \eta$ was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections $d^4\sigma/dtdQ^2dx_Bd\phi_\eta$ and structure functions $\sigma_U = \sigma_T+\epsilon\sigma_L, \sigma_{TT}$ and $\sigma_{LT}$, as functions of $t$ were obtained over a wide range of $Q^2$ and $x_B$. The $\eta$ structure functions are compared with those previously measured for $\pi^0$ at the same kinematics. At low $t$, both $\pi^0$ and $\eta$ are described reasonably well by generalized parton distributions (GPDs) in which chiral-odd transversity GPDs are dominant. The $\pi^0$ and $\eta$ data, when taken together, can facilitate the flavor decomposition of the transversity GPDs.