Probing short-range NN-correlations in the reaction 12C + p → p + pN + 10A

The exclusive reaction 12C(p, ppN)10A of quasi-elastic knockout of the nucleon from the short-rangecorrelated nucleon pair <NN> in the 12C nucleus by proton with an energy of few GeV is considered in the plane-wave approximation.The two-nucleon spectroscopic factors and momentum distributions of the center of mass motion of NN-pairs are considered by analogy with theory of quasi-elastic knockout of fast deuteron clusters from nuclei (p, Nd) using the translationally-invariant shell model.

Method simplifying calculation of coefficients of fractional parentage for translationally invariant shell-model

A new procedure for large-scale calculations of the coefficients of fractional parentage (CFP) for many-particle systems is presented. The approach is based on a simple enumeration scheme for antisymmetric N particle states, and we suggest an efficient method for constructing the eigenvectors of two-particle transposition operator $$P_{N_1 ,N}$$ in a subspace where N 1 and N 2 = N − N 1 nucleons basis states are already antisymmetrized. The main result of this paper is that according to permutation operators $$P_{N_1 ,N}$$ eigenvalues we can distinguish totally asymmetrical N particle states from the other states with lower degree of asymmetry.

CLUSTER–CLUSTER POTENTIALS FOR THE LITHIUM NUCLEI

Two types of cluster–cluster potentials are obtained for the lithium nuclei. The first is an attractive one and the second is a superposition of repulsive and attractive Gaussian forces. The ground-state wave functions of the lithium nuclei 6 Li , 7 Li , 8 Li , and 9 Li are expanded in terms of products of two wave functions: the first represents the set of A-4 nucleons and the second represents the set of the last four nucleons. In the construction of these wave functions, we have used the basis functions of the translation-invariant shell model. The expansion coefficients of the factorizations of these wave functions are products of four-particle orbital and spin-isospin fractional parentage coefficients. Two least-square formulas for the cluster–cluster potentials, which depend on the mass number A, are fitted for the lithium nuclei.