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Bakamjian-Thomas mass operator for the few-nucleon system from chiral dynamics

L. Girlanda·W. H. Klink·M. Viviani
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Abstract

We present an exploratory study consisting in the formulation of a relativistic quantum mechanics to describe the few-nucleon system at low energy, starting from the quantum field theoretical chiral Lagrangian involving pions and nucleons. To this aim we construct a Bakamjian-Thomas mass operator and perform a truncation of the Fock space which respects at each stage the relativistic covariance. Such truncation is justified, at sufficiently low energy, in the framework of a systematic chiral expansion. As an illustration we discuss the bound state observables and low-energy phaseshifts of the nucleon-nucleon and pion-nucleon scattering at the leading order of our scheme.

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L. Girlanda, W. H. Klink, M. Viviani. 2007-09-15. Bakamjian-Thomas mass operator for the few-nucleon system from chiral dynamics. https://doi.org/10.1103/physrevc.76.044002

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