Tetraquarks with colour-blind forces in chiral quark models

Abstract

We discuss the stability of multiquark systems within the recent model of Glozman et al. where the chromomagnetic hyperfine interaction is replaced by pseudoscalar-meson exchange contributions. We find that such an interaction binds a heavy tetraquark systems $QQ\bar{q}\bar{q}$ ($Q=c,bandq=u,d)$ by 0.2-0.4 GeV. This is at variance with results of previous models where $cc\bar{q}\bar{q}$ is unstable.

Comments: 10 pages, plain teX