Y-scaling and nucleon momentum distributions in few body systems and light nuclei

The basic elements of y-scaling, which takes properly into account nucleon binding and momentum are reviewed. A new method of analysis which allows one to obtain the experimental asymptotic scaling function from inclusive cross sections even if these data are affected by final state interactions is illustrated and the nucleon momentum distributions obtained by such a method are discussed. For few-body systems these momentum distributions satisfactorily agree with the ones extracted from (e,e'p) reactions and with theoretical calculations performed within Faddeev or variational approaches, whereas for complex nuclei they qualitatively agree with predictions of theoretical many-body approaches which take nucleon-nucleon correlations into account and disagree, at k≥350 MeV/c, with predictions by mean field approaches. (orig.)