S -wave KK∗ interactions in a finite volume and the f1 (1285)

Abstract

Lattice QCD simulations provide a promising way to disentangle different interpretations of hadronic resonances, which might be of particular relevance to understand the nature of the so-called XYZ particles. Recent studies have shown that in addition to the well-established naive quark model picture, the axial-vector meson f1(1285) can also be understood as a dynamically generated state built upon the KK∗ interaction. In this work, we calculate the energy levels of the KK∗ system in the f1(1285) channel in finite volume using the chiral unitary approach. We propose to calculate the loop function in the dimensional regularization scheme, which is equivalent to the hybrid approach adopted in previous studies. We also study the inverse problem of extracting the bound state information from synthetic lattice QCD data and comment on the difference between our approach and the Lüscher method.