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arXiv · 2506.15406

Towards a microscopic description of nucleus-nucleus collisions

Matteo Vorabbi·Michael Gennari·Paolo Finelli·Carlotta Giusti·Petr Navrátil
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Abstract

We present the first results of a comprehensive microscopic approach to describe nucleus-nucleus elastic collisions by means of an optical potential derived at first order in multiple-scattering theory and computed by folding the projectile and target nuclear densities with the nucleon-nucleon $t$ matrix, which describes the interaction between each nucleon of the projectile and each nucleon of the target. Chiral interactions are consistently used in the calculation of the $t$ matrix and of the nonlocal nuclear densities, which are computed within the ab initio no-core shell model. Cross sections calculated for $\alpha$ collisions on $^{12}$C and $^{16}$O at projectile energies in the range 100-300 MeV are presented and compared with available data. For momentum transfer $q$ up to about $1.0$ fm$^{-1}$ our results are in good agreement with the experimental data, whereas for higher momenta a reduction of the imaginary contributions is needed.

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Matteo Vorabbi, Michael Gennari, Paolo Finelli, Carlotta Giusti, Petr Navrátil. 2025-06-18. Towards a microscopic description of nucleus-nucleus collisions. https://arxiv.org/abs/2506.15406

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