Electromagnetic response of 12C: a first-principles calculation

TL;DR

This paper presents a first-principles Green's function Monte Carlo calculation of $^{12}$C's electromagnetic responses, showing excellent agreement with experimental data and no evidence of quenching, thus advancing nuclear structure understanding.

Contribution

It introduces a comprehensive ab initio calculation of $^{12}$C's electromagnetic responses using realistic interactions and confirms the absence of response quenching.

Findings

Excellent agreement between theory and experiment.

No evidence for quenching of the longitudinal response.

Re-analysis of Coulomb sum rule supports findings.

Abstract

The longitudinal and transverse electromagnetic response functions of $^{12}$C are computed in a "first-principles" Green's function Monte Carlo calculation, based on realistic two- and three-nucleon interactions and associated one- and two-body currents. We find excellent agreement between theory and experiment and, in particular, no evidence for the quenching of measured versus calculated longitudinal response. This is further corroborated by a re-analysis of the Coulomb sum rule, in which the contributions from the low-lying $J^\pi\,$=$\, 2^+$, $0^+_2$ (Hoyle), and $4^+$ states in $^{12}$C are accounted for explicitly in evaluating the total inelastic strength.