Signatures of the chiral two-pion exchange electromagnetic currents in the 2H and 3He photodisintegration reactions

TL;DR

This paper investigates the impact of long-range two-pion exchange electromagnetic currents derived from chiral effective field theory on the photodisintegration reactions of deuterium and helium-3, comparing predictions with experimental data.

Contribution

It introduces the use of NLO chiral two-pion exchange currents in describing electromagnetic nuclear reactions and assesses their effects across different NN potential parametrizations.

Findings

Long-range TPE currents improve agreement with experimental data.

Predictions are consistent with AV18 potential results.

Theoretical uncertainties are estimated using multiple NN potential parametrizations.

Abstract

The recently derived long-range two-pion exchange (TPE) contributions to the nuclear current operator which appear at next-to-leading order (NLO) of the chiral expansion are used to describe electromagnetic processes. We study their role in the photodisintegration of 2H and 3He and compare our predictions with experimental data. The bound and scattering states are calculated using five different parametrizations of the chiral next-to-next-to-leading order (N2LO) nucleon-nucleon (NN) potential which allows us to estimate the theoretical uncertainty at a given order in the chiral expansion. For some observables the results are very close to the predictions based on the AV18 NN potential and the current operator (partly) consistent with this force. In the most cases, the addition of long-range TPE currents improved the description of the experimental data.