Studies of Proton Momentum Distributions in Light Nuclei

Studies of proton momenum distributions inside light nuclei have attracted significant interest from both experimentalists and theoreticians for decades. This talk review what we have learned about the proton distributions in ³He and ⁴He nuclei with a focus on the most recent results obtained from Hall A on ⁴He at Jefferson Lab. This experimental determined cross sections for the 4He(e,e′p)X reactions in the missing energy range from 0.017 to 0.022 GeV and up to a missing momentum of 0.632 GeV/c at x_B=1.24 and Q²=2 (GeV/c). The results have been compared to relativistic distorted-wave impulse approximation calculations and show significantly more events for pm≥0.45 GeV/c than are predicted by the theoretical along with a striking fluctuation in the ratio of data to the theoretical model around pm=0.3GeV/c pointing to possible signals of initial-state multinucleon correlations.