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تسجيل مستخدم جديدImproved description of light nuclei through chiral effective field theory at leading order
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We propose an arrangement of the most commonly invoked version of the two-nucleon chiral potential such that the low-lying amplitude zero of the 1S0 partial wave is captured at leading order of the effective expansion. Adopting other partial waves from the LENPIC interaction, we show how this modification yields an improved description of ground-state energies and point-proton radii of three test nuclei.
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We explore the effects on nuclear bulk properties of using regularization cutoffs larger than the nucleon mass within the chiral effective field theory using a power counting that ensures order-by-order renormalization in the two-nucleon system. To d
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Song et al. [Phys. Rev. C 102, 065208 (2020)] presented results for the $Lambda_c N$ interaction based on an extrapolation of lattice simulations by the HAL QCD Collaboration at unphysical quark masses to the physical point via covariant chiral effec
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Motivated by the recent experimental measurements of differential cross sections of the $Sigma^{-}p$ elastic scattering in the momentum range of $470$ to $850$ MeV$/c$ by the J-PARC E$40$ experiment, we extend our previous studies of $S=-1$ hyperon-n
ucleon interactions to relatively higher energies up to $900$ MeV$/c$ for both the coupled-channel $Lambda prightarrow(Lambda p, Sigma^{+}n, Sigma^{0}p)$, $Sigma^{-}prightarrow(Lambda n, Sigma^{0}n, Sigma^{-}p)$ and single-channel $Sigma^{+}prightarrowSigma^{+}p$ reactions. We show that although the leading order covariant chiral effective field theory is only constrained by the low energy data, it can describe the high energy data very well, in particular, the J-PARC E40 differential cross sections. In particular, we predict a pronounced cusp structure close to the $Sigma N$ threshold in the $Lambda pto Lambda p$ reaction, which can be checked in the future using, e.g., the Femtoscopy technique. The predicted total and differential cross sections are of relevance for ongoing and planned experiments.
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