Donald F. Geesaman, Physics Division, Argonne Nat. Lab.,
How vanilla is your proton?
Physics Division Colloquium - 11 Feb 2000

While the property of the quark flavor played a leading role in the development of the quark model, in Quantum Chromodynamics, the theory of the strong interaction, flavor only appears in the quark mass terms. In particular, for many years the sea of quark-antiquark pairs in hadrons was assumed to be flavor symmetric, at least for the light up and down quarks. Recent direct measurements of the flavor dependence of the quark sea in the proton reveal a large flavor dependence which gives new insight into the structure of bound hadronic states. Our current knowledge of the flavor dependence of the sea, from hard scattering reactions and hadronic form factors, will be reviewed and some of the implications for hadron structure will be discussed as we seek a more complete understanding of the non-perturbative aspects of Quantum Chromodynamics.

ANL Physics Division Colloquium Schedule