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arXiv · 2508.02200

$A=2,3,4$ nuclear contact coefficients in the generalized contact formalism

E. Proietti·L. E. Marcucci·M. Viviani
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Abstract

We present a theoretical calculation for the $A = 2, 3$ and 4 nuclear contact coefficients within the generalized contact formalism, using both local and non-local chiral potentials. The Hyperspherical Harmonics method is employed to calculate the nuclear wave functions, from which we derive two-body momentum distributions and density functions to extract the contact coefficients. We have extracted the contact coefficients from two-body momentum distributions or from density functions, for a given nucleus and potential, and we have found that the generalized contact formalism predictions are verified in the triplet spin channel for local and non-local potentials. On the other hand, some significant tensions exist for the singlet channels, especially when studied with non-local potentials. We have also analyzed the model-independence of the ratios between the contact coefficients, and we have found to be quite satisfied. This study extends previous works based on local interaction models only.

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E. Proietti, L. E. Marcucci, M. Viviani. 2025-08-04. $A=2,3,4$ nuclear contact coefficients in the generalized contact formalism. https://arxiv.org/abs/2508.02200

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