Convergence of nuclear effective field theory with perturbative pions

Journal Article · Wed Sep 16 00:00:00 EDT 2020 · Physical Review C

DOI:https://doi.org/10.1103/physrevc.102.034004· OSTI ID:1799979

Kaplan, David B. ^[1]

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1. Univ. of Washington, Seattle, WA (United States); OSTI

The classic paper by Fleming, Mehen, and Stewart (FMS) cast doubts on the convergence of spin-triplet nucleon-nucleon partial wave scattering amplitudes when following the proposal of Kaplan, Savage, and Wise to construct nuclear effective field theory (EFT) around the unitary fermion limit with perturbative pion exchange. FMS identified the subclass of iterated one-pion exchange potential graphs as the cause of this poor convergence, which they showed persisted in the chiral limit. Theoretical tools are developed in this work to compute these Feynman graphs analytically to high order in all angular momentum channels simultaneously, examining the amplitudes computed to seven loops in the $$\textit{L = J}$$ channels and three loops in the coupled $$\textit{L = J}$$ ± 1 channels. One finds that there is nothing pathological about the perturbative expansion of a 1/$r^3$ potential in general and that the expansion converges satisfactorily in all partial waves except those with the lowest angular momentum, particularly the $$^3P_0$$ and the coupled $$^3S_1 - ^3D_1$$ channels. The results corroborate work by Birse, which suggests possible avenues to explore for improving the range of validity of the EFT expansion.

• Research Organization: Univ. of Washington, Seattle, WA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: FG02-00ER41132
• OSTI ID: 1799979
• Journal Information: Physical Review C, Journal Name: Physical Review C Journal Issue: 3 Vol. 102; ISSN 2469-9985
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
Physics