The $\gamma p \to n a^+_2(1320) \to n \rho^0 \pi^+$ reactions within an effective Lagrangian approach

TL;DR

This paper models the production of the $a_2(1320)$ meson in photon-proton reactions using an effective Lagrangian approach, successfully describing experimental data and providing predictions for future experimental tests.

Contribution

It introduces a detailed effective Lagrangian model for $a_2(1320)$ meson production in photon-proton reactions, focusing on $t$-channel $ ext{pi}^+$ exchange and offering predictions for observables.

Findings

Good agreement with experimental total cross section data for $ ext{gamma} p o n a_2^+(1320)$

Predictions for invariant mass distributions and Dalitz plots for $ ext{gamma} p o n ho^0 ext{pi}^+$

Theoretical framework can be tested by future experiments.

Abstract

We investigate the $a_2(1320)$ meson photon production in the $\gamma p \to n a^+_2(1320)$ and $\gamma p \to n \rho^0 \pi^+$ reactions within the effective Lagrangian method. For $\gamma p \to n a^+_2(1320)$ reaction, by considering the contributions only from the $t-$channel $\pi^+$ exchange, we get a fairly good description of the current experimental total cross section data. We also studied the $\gamma p \to n \rho^0 \pi^+$ reaction, which mainly contribute to the $\gamma p \to n \pi^+ \pi^+ \pi^-$ reaction. The latter reaction has measured by the CLAS Collaboration. The total cross sections, invariant mass distribution, and the Dalitz Plot of $\gamma p \to n \rho^0 \pi^+$ reaction are shown, which can be tested by future experiments.