The double life of the X meson

Abstract

The molecule and the tetraquark model are the two competing interpretations of the X(3872). I will briefly comment on how far these two pictures are really resolvable by the experiment, and I will give a concise account on a new method for defining the quark content of hadrons at heavy-ion colliders.

Comments: 6 pages, to appear in the Proceedings of IFAE2006, Pavia, Italy