Studies on the polarization transfer coefficients C_x and C_z in the gamma p -> K^+ Lambda(1520,3/2^-) reaction process

TL;DR

This study analyzes polarization transfer coefficients in the gamma p -> K^+ Lambda(1520) reaction using an effective Lagrangian approach, highlighting the dominant roles of contact and K-exchange contributions in polarization transfer.

Contribution

It introduces a detailed calculation of polarization transfer coefficients including nucleon resonance effects and identifies the dominant mechanisms affecting polarization transfer.

Findings

K-exchange significantly enhances C_x polarization transfer.

Contact and K-exchange contributions dominate polarization transfer.

Negligible effects from K^*-exchange and D_{13}(2080) resonance.

Abstract

We investigate the polarization transfer coefficients C_(x,z) for the gamma p -> K^+ Lambda(1520,3/2^-) reaction process, in which the photon is polarized circularly and the Lambda(1520,3/2^-) along the x- or z-axis. To this end, we employ the effective Lagrangian method at tree level and the gauge-invariant form factor scheme. In addition to the Born terms, (s,u,t_K,t_K^*)-channels and contact term, we include the nucleon resonance D_{13}(2080) in the s-channel. We compute the C_(x,z) as functions of theta_K as well as E_cm. It turns out that the K^*-exchange and D_{13} contributions are negligible within available experimental and theoretical inputs for them. In contrast, we observe that the contact and K-exchange contributions play dominant roles for determining the C_(x,z). Especially, the $K$-exchange enhances the transverse polarization transfer C_x considerably.