a₀(980) as a dynamically generated resonance in the extended Linear Sigma Model

We study basic properties of scalar hadronic resonances within the so-called extended linear sigma model (eLSM), which is an effective model of QCD based on chiral symmetry and dilatation invariance. In particular, we focus on the mass and decay width of the isovector state a₀(1450) and perform a numerical study of the propagator pole(s) on the unphysical Riemann sheets. Here, the a₀(1450) is understood as a seed state explicitly included in the eLSM - this is in fact not true for the corresponding resonance below 1 GeV, the a₀(980), which is sometimes interpreted as a kaonic (i.e., dynamically generated) bound state. In our work we want to clarify if the yet not included a₀(980) can be found as a propagator pole generated by hadronic loop contributions. From such an investigation one could learn more about the general dependence of the eLSM - and effective field models in general - on strongly coupled hadronic intermediate states, possibly giving new insight into the low-energy regime, scalar resonances and both its theoretical description and physical interpretation.