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arXiv · 0801.2743

Four-nucleon system with $Δ$-isobar excitation

A. Deltuva·A. C. Fonseca·P. U. Sauer
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Abstract

The four-nucleon bound state and scattering below three-body breakup threshold are described based on the realistic coupled-channel potential CD Bonn + $Δ$ which allows the excitation of a single nucleon to a $Δ$ isobar. The Coulomb repulsion between protons is included. In the four-nucleon system the two-baryon coupled-channel potential yields effective two-, three- and four-nucleon forces, mediated by the $Δ$ isobar and consistent with each other and with the underlying two-nucleon force. The effect of the four-nucleon force on the studied observables is much smaller than the effect of the three-nucleon force. The inclusion of the $Δ$ isobar is unable to resolve the existing discrepancies with the experimental data.

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A. Deltuva, A. C. Fonseca, P. U. Sauer. 2008-01-17. Four-nucleon system with $Δ$-isobar excitation. https://doi.org/10.1016/j.physletb.2007.12.058

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