Twist-3 generalized parton distributions of sea quarks at zero skewness in the light-cone quark model

Abstract

We present a systematic study of twist-3 generalized parton distributions (GPDs) for $\bar{u}$ and $\bar{d}$ sea quarks in the proton at zero skewness ($\xi =0$) using the light-cone formalism with overlap representation. The proton wave functions are derived from a meson-baryon fluctuation model that incorporates $|q\bar{q}B⟩$ Fock states, providing a natural framework for investigating sea quark contributions. Within this approach, we compute the complete set of twist-3 GPDs and present the numerical results, including both chiral-odd ($H_2$, $E_2$, ${\tilde{E}}_2$, ${\tilde{H}}_2^{\prime }$) and chiral-even (${\tilde{E}}_{2T}$, $H_{2T}^{\prime }$, $E_{2T}^{\prime }$, ${\tilde{H}}_{2T}^{\prime }$) distributions for $\bar{u}$ and $\bar{d}$ quarks at zero skewness. By taking the forward limit, we also calculate the corresponding twist-3 parton distribution functions $e(x)$ of $\bar{u}$ and $\bar{d}$ quarks. The kinetic orbital angular momenta of sea quarks deduced from the twist-3 GPDs are studied and compared to those from the twist-2 GPDs.

Comments: 13 pages, 6 figures