Eur. Phys. J. C (2016) 76: 573
https://doi.org/10.1140/epjc/s10052-016-4427-8

Regular Article - Theoretical Physics

: confronting theory and lattice simulations

Instituto de Física Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigación de Paterna, Aptdo. 22085, 46071, Valencia, Spain

^* e-mail: miguelalbaladejo@gmail.com

Received: 10 June 2016
Accepted: 10 October 2016
Published online: 24 October 2016

Abstract

We consider a recent T-matrix analysis by Albaladejo et al. (Phys Lett B 755:337, 2016), which accounts for the and coupled-channels dynamics, and which successfully describes the experimental information concerning the recently discovered . Within such scheme, the data can be similarly well described in two different scenarios, where is either a resonance or a virtual state. To shed light into the nature of this state, we apply this formalism in a finite box with the aim of comparing with recent Lattice QCD (LQCD) simulations. We see that the energy levels obtained for both scenarios agree well with those obtained in the single-volume LQCD simulation reported in Prelovsek et al. (Phys Rev D 91:014504, 2015), thus making it difficult to disentangle the two possibilities. We also study the volume dependence of the energy levels obtained with our formalism and suggest that LQCD simulations performed at several volumes could help in discerning the actual nature of the intriguing state.