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Tensor Forces and the Ground-State Structure of Nuclei

R. Schiavilla·R. B. Wiringa·Steven C. Pieper·J. Carlson
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Abstract

Two-nucleon momentum distributions are calculated for the ground states of nuclei with mass number $A\leq 8$, using variational Monte Carlo wave functions derived from a realistic Hamiltonian with two- and three-nucleon potentials. The momentum distribution of $np$ pairs is found to be much larger than that of $pp$ pairs for values of the relative momentum in the range (300--600) MeV/c and vanishing total momentum. This order of magnitude difference is seen in all nuclei considered and has a universal character originating from the tensor components present in any realistic nucleon-nucleon potential. The correlations induced by the tensor force strongly influence the structure of $np$ pairs, which are predominantly in deuteron-like states, while they are ineffective for $pp$ pairs, which are mostly in $^1$S$_0$ states. These features should be easily observable in two-nucleon knock-out processes, such as $A(e,e^\prime np)$ and $A(e,e^\prime pp)$.

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R. Schiavilla, R. B. Wiringa, Steven C. Pieper, J. Carlson. 2006-11-10. Tensor Forces and the Ground-State Structure of Nuclei. https://doi.org/10.1103/physrevlett.98.132501

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