Probing the Deuteron at Very Large Internal Momenta

We measure H2(e,e′p)n cross sections at 4-momentum transfers of Q2=4.5±0.5 (GeV/c)2 over a range of neutron recoil momenta pr, reaching up to ∼1.0 GeV/c. We obtain data at fixed neutron recoil angles θnq=35°, 45°, and 75° with respect to the 3-momentum transfer q→. The new data agree well with previous data, which reached pr∼500 MeV/c. At θnq=35° and 45°, final state interactions, meson exchange currents, and isobar currents are suppressed and the plane wave impulse approximation provides the dominant cross section contribution. We compare the new data to recent theoretical calculations, where we observe a significant discrepancy for recoil momenta pr>700 MeV/c.