The role of the $N^*(2080)$ resonance in the $\vec{\gamma} p \to K^+ \Lambda(1520)$ reaction

TL;DR

This paper studies the role of the $N^*(2080)$ resonance in $ar{ ext{γ}} p o K^+ ext{Λ}(1520)$ reactions, showing it improves cross section predictions but not asymmetry fits, thus aiding understanding of this nucleon resonance.

Contribution

It introduces the $N^*(2080)$ resonance into the effective Lagrangian model for $ ext{Λ}(1520)$ photoproduction, providing a better fit to differential cross section data.

Findings

Inclusion of $N^*(2080)$ improves cross section description.

Model fits well to differential cross sections.

Discrepancies remain in photon-beam asymmetry predictions.

Abstract

We investigate the $\Lambda(1520)$ photo-production in the $\vec{\gamma} p \to K^+ \Lambda(1520)$ reaction within the effective Lagrangian method near threshold. In addition to the "background" contributions from the contact, $t-$channel $K$ exchange, and $s-$channel nucleon pole terms, which were already considered in previous works, the contribution from the nucleon resonance $N^*(2080)$ (spin-parity $J^P = 3/2^-$) is also considered. We show that the inclusion of the nucleon resonance $N^*(2080)$ leads to a fairly good description of the new LEPS differential cross section data, and that these measurements can be used to determine some of the properties of this latter resonance. However, serious discrepancies appear when the predictions of the model are compared to the photon-beam asymmetry also measured by the LEPS Collaboration.