Quark Momentum Distributions Beyond the Free Nucleon Limit
This paper, coauthored by Nadia Fomin, a former UVa graduate student (and now a research associate at the University of Tennessee), Donal Day (her advisor at UVa), John Arrington of Argonne National Lab and others, provides for the first time a direct connection between inclusive electron-nucleus data taken at Jefferson Lab's momentum transfers with data at momentum transfers 10 times higher. This connection is important because it allows an examination of the quark momentum distributions at momenta forbidden in the free nucleon. These data are snapshots of the behavior of quarks under certain extreme conditions possible only inside the nucleus - rare fluctuations in which nucleons overlap, generating very high densities and violent reactions. Theories that attempt to describe the dynamics by which a quark obtains such large momenta - be it parton recombination or the presence of pre-existing exotic 6 or 9-quark states, or some combination with conventional nuclear physics - will find a testing ground here.