  A model to study two-proton emission processes induced by electron scattering
is developed. The process is induced by one-body electromagnetic operators
acting together with short-range correlations, and by two-body $\Delta$
currents. The model includes all the diagrams containing a single correlation
function. A test of the sensitivity of the model to the various theoretical
inputs is done. An investigation of the relevance of the $\Delta$ currents is
done by changing the final state angular momentum, excitation energy and
momentum transfer. The sensitivity of the cross section to the details of the
correlation function is studied by using realistic and schematic correlations.
Results for $^{12}$C, $^{16}$O and $^{40}$Ca nuclei are presented.
