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arXiv · 1903.09976

A Solution to the Quenched ${g_A}$ Problem in Nuclei and Dense Baryonic Matter

Mannque Rho
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Abstract

When scale symmetry is combined with chiral symmetry in a scale-chiral Lagrangian, it can be shown in Fermi-liquid fixed point theory that $g_A^{\rm eff}\approx 1$ in finite nuclei {\it as well as} in dense baryonic matter. This is suggested as a signal for emergence of hidden symmetries of QCD in baryonic matter from low to very high density. This calculation throws doubt on the "first principles" explanation of the quenching of $g_A$ in nuclei with two-body meson-exchange currents. It also has relevance to Gamow-Teller matrix elements in neutrinoless double $\beta$ decay.

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Mannque Rho. 2019-03-24. A Solution to the Quenched ${g_A}$ Problem in Nuclei and Dense Baryonic Matter. https://arxiv.org/abs/1903.09976

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