Towards observation of three-nucleon short-range correlations in high Q^2 A(e, e')X reactions

Abstract

We present a detailed study of kinematical and dynamical conditions necessary for probing highly elusive three-nucleon short range correlations~(3N-SRCs) in nuclei through inclusive electron scattering. The kinematic requirements that should be satisfied in order to isolate 3N-SRCs in inclusive processes are derived. We demonstrate that a sequence of two short-range NN interactions represents the main mechanism for 3N-SRCs in inclusive processes. Within this mechanism we predict a quadratic dependence of the inclusive cross section ratios of nuclei to $^3$He in the 3N-SRC region to the same ratio measured in 2N-SRC domain. The extended analysis of the available data satisfying the necessary 3N-SRC kinematical conditions is presented. This analysis provides tantalizing signatures of scaling associated with the onset of 3N-SRC dominance. The same data are also consistent with the prediction of the quadratic relation between the ratios measured in the 3N and 2N-SRC regions for nuclei ranging $4 \le A \le 197$. This agreement made it possible to extract $a_3(A)$, the probability of 3N-SRCs relative to the A=3 nucleus. We find $a_3(A)$ to be significantly larger in magnitude than the analogous parameter, $a_2(A)$, for 2N-SRCs.