From pions to pentaquarks
arXiv:hep-ph/0406043
Abstract
I overview the physical picture of QCD at low energies that has led to the prediction of a narrow exotic baryon Theta^+ which cannot be made of three quarks. The very narrow width of the Theta^+ and a possible reason why it is seen in low- but not in high-energy experiments are briefly discussed.
Invited talks at the meeting of the American Physical Society (Denver) and at the workshop `Continuous Advances in QCD' (Minneapolis). 13 p., 19 figs