The WA3 data and the two $K_1(1270)$ resonances

TL;DR

This paper analyzes WA3 experimental data on kaon-proton interactions using unitary chiral perturbation theory, providing evidence for two distinct $K_1(1270)$ resonances, thus advancing understanding of axial vector mesons.

Contribution

It offers a novel analysis of experimental data supporting the existence of two separate $K_1(1270)$ states predicted by U$\chi$PT, enhancing meson resonance models.

Findings

Support for two $K_1(1270)$ resonances

Validation of U$\chi$PT predictions

Analysis of WA3 data at 63 GeV

Abstract

Recent studies based on unitary chiral perturbation theory (U$\chi$PT) found that the low-lying axial vector mesons can be dynamically generated due to the interaction of the pseudoscalar octet of the pion and the vector nonet of the rho. In particular, two poles in the second Riemann sheet have been associated to the nominal $K_1(1270)$ resonance. In this talk, we present a recent analysis of the WA3 data on $K^-p\to K^-\pi^+\pi^- p$ at 63 GeV using the U$\chi$PT amplitudes, and show that it is in favor of the existence of two $K_1(1270)$'s [Phys. Rev. D 75, 014017 (2007)].