Exclusive electroproduction of strange mesons with JLab 12 GeV

TL;DR

This paper discusses planned high-Q^2 exclusive electroproduction experiments of strange mesons at Jefferson Lab 12 GeV, aiming to explore reaction mechanisms and extract baryon structure information through GPDs.

Contribution

It proposes new experimental measurements to investigate the nucleon's gluon and quark GPDs using exclusive strange meson production at Jefferson Lab.

Findings

Probing the transverse spatial distribution of gluons in the nucleon.

Separating nucleon helicity-flip and non-flip GPDs via recoil polarization.

Analyzing strangeness polarization in the nucleon.

Abstract

We summarize the physics topics which can be addressed by measurements of high-Q^2 exclusive electroproduction of strange mesons, gamma* N -> phi N, K* Lambda, K Lambda, K Sigma, at Jefferson Lab with 11 GeV beam energy. The proposed investigations are aimed both at exploring the reaction mechanism (dominance of point-like configurations) and extracting information about baryon structure from the data (generalized parton distributions, or GPDs). They include (a) probing the t-dependence of the nucleon's gluon GPD (transverse spatial distribution of gluons) in phi meson production; (b) separating the nucleon helicity-flip and nonflip quark GPDs in K* Lambda production with measurement of the Lambda recoil polarization; (c) probing strangeness polarization in the nucleon in K Lambda and K Sigma production. These studies rely only on the analysis of cross section ratios, which are less affected by the theoretical uncertainties of present GPD-based calculations than absolute cross sections.