Eur. Phys. J. A (2007) 31: 543-548
https://doi.org/10.1140/epja/i2006-10193-6

QNP 2006

Towards an understanding of the light scalar mesons

Institut für Kernphysik, Forschungszentrum Jülich, D-52425, Jülich, Germany

^* e-mail: c.hanhart@fz-juelich.de

Received: 8 October 2006
Accepted: 15 October 2006
Published online: 23 February 2007

Abstract

Although studied for many years the nature of the light scalar mesons remains controversial. Here we shall present a method, applicable for s-wave states located close to a threshold, that allows one to quantify the molecular part of a given state. When applied to the f ₀(980) a dominance of the molecular component is found. In the second part, we show that requirements of field-theoretic consistency and chiral symmetry, when applied to the scattering of light pseudo-scalars, naturally lead to the appearance of dynamical poles in the scalar sector. A program is proposed on how to further investigate experimentally the mixing between these dynamical states and possible genuine quark states.