Electron-Induced Neutron Knockout fromH4e

Abstract

The differential cross section for electron-induced neutron knockout in the reaction 4He(e,e(')n)(3)He has been measured for the first time with a statistical accuracy of 11%. The experiment was performed in quasielastic kinematics at a momentum transfer of 300 MeV/c and in the missing-momentum range of 25-70 MeV/c. The comparison of the data with theoretical calculations shows an impressive increase of the cross section resulting from final state interaction effects. Specifically, the p-n charge-exchange process dominates the cross section in this kinematical regime.

Deeply virtual Compton scattering off nuclei

“…In abscence of free neutron targets, few-body systems are often used as effective neutron targets. Typically, the deuterium is considered as a free neutron target and polarized 3 He as an effective polarized neutron target; higher mass nuclei feature important contributions from other reaction mechanisms which make the spectator nucleon picture unreliable [43].…”

“…6) which shows that the beam polarized cross section difference off the neutron is, similarly to the transversely polarized target spin asymmetry, sensitive to the least known and constrained GPD E [28] of particular importance in the angular momentum sum rule [1]. AHLT GPDs [41] Lattice QCDSF (quenched) [42] Lattice QCDSF (unquenched) [43] LHPC Lattice (connected terms) [44] A.W. Thomas [45] Figure 6.…”