Tensor Correlations Measured in 3He(e,e'pp)n

TL;DR

This study measures the ratio of proton-proton to proton-neutron pairs in helium-3 at high energy, revealing the dominance of tensor correlations over central ones at specific momenta, providing new insights into nuclear force interactions.

Contribution

First measurement of the pp to pn pair ratio as a function of pair total momentum in 3He(e,e'pp)n reactions, highlighting tensor correlation dominance.

Findings

pp to pn ratio increases with pair total momentum

Tensor correlations dominate over central correlations at certain momenta

Provides new data on nucleon pair correlations in helium-3

Abstract

We have measured the 3He(e,e'pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum, $p_{tot}$. For pair relative momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low $p_{tot}$ and rises to approximately 0.5 at large $p_{tot}$. This shows the dominance of tensor over central correlations at this relative momentum.