12C(e,e'pN) measurements of short range correlations in the tensor-to-scalar interaction transition region
High-momentum configurations of nucleon pairs at short-distance are probed using measurements of the 12C(e,e′p) and 12C(e,e′pN) reactions (where N is either n or p), at high-Q2 and xB>1.1. The data span a missing-momentum range of 300–1000 MeV/c and are predominantly sensitive to the transition region of the strong nuclear interaction from a Tensor to Scalar interaction. The data are well reproduced by theoretical calculations using the Generalized Contact Formalism with both chiral and phenomenological nucleon-nucleon (NN) interaction models. This agreement suggests that the measured high missing-momentum protons up to 1000 MeV/c predominantly belong to short-ranged correlated (SRC) pairs. The measured 12C(e,e′pN) / 12C(e,e′p) and 12C(e,e′pp) / 12C(e,e′pn) cross-section ratios are consistent with a decrease in the fraction of proton-neutron SRC pairs and increase in the fraction of proton-proton SRC pairs with increasing missing momentum. This confirms the transition from an isospin-dependent tensor NN interaction at ∼400 MeV/c to an isospin-independent scalar interaction at high-momentum around ∼800 MeV/c as predicted by theoretical calculation.
Korover, I.; Pybus, J. R.; Schmidt, A.; Hauenstein, F.; Duer, M.; Hen, O.; Piasetzky, E.; Weinstein, L. B.; Higinbotham, D. W.; Adhikari, S.; Adhikari, K.; Amaryan, M. J.; Angelini, Giovanni; Atac, H.; Barion, L.; Battaglieri, M.; Beck, A.; Bedlinskiy, I.; Benmokhtar, Fatiha; Bianconi, A.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Bulumulla, D.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chatagnon, P.; and Djalali, C., "12C(e,e'pN) measurements of short range correlations in the tensor-to-scalar interaction transition region" (2021). Physics & Astronomy Open Access Publications. 164.