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arXiv · 1504.05233

Ab Initio Approach to the Non-Perturbative Scalar Yukawa Model

Yang Li·V. A. Karmanov·P. Maris·J. P. Vary
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Abstract

We report on the first non-perturbative calculation of the scalar Yukawa model in the single-nucleon sector up to four-body Fock sector truncation (one "scalar nucleon" and three "scalar pions"). The light-front Hamiltonian approach with a systematic non-perturbative renormalization is applied. We study the $n$-body norms and the electromagnetic form factor. We find that the one- and two-body contributions dominate up to coupling $α\approx 1.7$. As we approach the coupling $α\approx 2.2$, we discover that the four-body contribution rises rapidly and overtakes the two- and three-body contributions. By comparing with lower sector truncations, we show that the form factor converges with respect to the Fock sector expansion.

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Yang Li, V. A. Karmanov, P. Maris, J. P. Vary. 2015-07-09. Ab Initio Approach to the Non-Perturbative Scalar Yukawa Model. https://doi.org/10.1016/j.physletb.2015.07.014

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