Wayne State University Physics Colloquium Series
Richard Jones
University of Connecticut
The Standard Model provides a picture of hadrons as composed of a large number of light quarks and gluons called partons. Calculating observable quantities in the full theory is expensive, but a high priority. The quark models, on the other hand, seek an economical description in terms of a limited number of degrees of freedom. They give a very good description of the experimental spectrum of heavy quarkonia and of the heavy quark-antiquark potential. The quark model is on less firm ground when applied to systems of light quarks, and experimental evidence is now accumulating for so-called exotic states which cannot be accomodated by bound states of quarks alone. The existence and pattern of these new particles promises important new information on the way that partons are confined in hadrons. An new experiment is being planned to exploit 12GeV photons at Jefferson Lab in search of exotic mesons.
4:00pm February 22, 2001