Studying few-body nuclear targets in the (e,e'p) reaction
is a powerful method to investigate specific aspects of the nucleus.
The 4He nucleus is an especially interesting target since it has
many of the ingredients of a complex, heavy nucleus, while as an A=4
system, microscopic calculations are still feasible.
Making use of the high luminosity electron beam at Jefferson Lab
together with the high resolution spectrometers in Hall A,
Jefferson Lab Hall A experiment E97-111 has measured the
4He(e,e'p)3He cross section at recoil momenta up to~500 MeV/c in various
kinematics. In plane-wave impulse approximation, many calculations
predict a sharp minimum in the cross section for recoil
momenta around 450~MeV/c and show that its location
is sensitive to the short-range part of the internucleon potential.
However, reaction dynamic effects such as final-state
interactions and meson-exchange currents can obscure such a minimum.
Measuring this cross section at various kinematical settings over the
same recoil-momentum range gives the possibility to study these reaction
dynamics effects. Preliminary results of this experiment will be
presented, and will be compared to recent theoretical predictions.