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arXiv · 1003.4383

Effective field theory of 3He

Shung-ichi Ando·Michael C. Birse
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Abstract

3He and the triton are studied as three-body bound states in the effective field theory without pions. We study 3He using the set of integral equations developed by Kok et al. which includes the full off-shell T-matrix for the Coulomb interaction between the protons. To leading order, the theory contains: two-body contact interactions whose renormalized strengths are set by the NN scattering lengths, the Coulomb potential, and a three-body contact interaction. We solve the three coupled integral equations with a sharp momentum cutoff, Lambda, and find that a three-body interaction is required in 3He at leading order, as in the triton. It also exhibits the same limit-cycle behavior as a function of Lambda, showing that the Efimov effect remains in the presence of the Coulomb interaction. We also obtain the difference between the strengths of the three-body forces in 3He and the triton.

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Shung-ichi Ando, Michael C. Birse. 2010-06-28. Effective field theory of 3He. https://doi.org/10.1088/0954-3899%2F37%2F10%2F105108

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