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Chiral Lagrangian Approach to Exchange Vector Currents in Nuclei

Tae-Sun Park·Dong-Pil Min·Mannque Rho
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Abstract

Exchange vector currents are calculated up to one-loop order (corresponding to next-to-next-to-leading order) in chiral perturbation theory. As an illustration of the power of the approach, we apply the formalism to the classic nuclear process $n+p\rightarrow d +γ$ at thermal energy. The exchange current correction comes out to be $(4.5 \pm 0.3)$ \% in amplitude giving a predicted cross section $σ= (334\pm 3)\ {\mbox mb}$ in excellent agreement with the experimental value $(334.2\pm 0.5)\ {\mbox mb}$. Together with the axial charge transitions computed previously, this result provides a strong support for the power of chiral Lagrangians in nuclear physics. As a by-product of our results, we suggest an open problem in the application of chiral Lagrangian approach to nuclear processes that has to do with giving a physical meaning to the short-range correlations that play an important role in nuclei.

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Tae-Sun Park, Dong-Pil Min, Mannque Rho. 1995-05-12. Chiral Lagrangian Approach to Exchange Vector Currents in Nuclei. https://doi.org/10.1016/0375-9474(95)00406-8

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