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arXiv · hep-ph/9901240

Barions as Solitons in Quantum SU(2) Skyrme Model

Abstract

This paper is a PhD thesis defended at Institute of Theoretical Physics and Astronomy on 18 December, 1998. The following (abbreviated) statements represent the main results of the work: 1.Each of SU(2) representation j yields the different quantum Lagrangian density. As a consequence, theoretical observables depend on representation j which can be treated as a new phenomenological parameter. 2.Quantum chiral solitons exist and possess asymptotic behaviour consistent with the massive Yukawa field fall. The asymptotic shape and PCAC relation leads to the correct asymptotic equation coinciding with contribution of explicitly broken term. 3.A nucleon and Δ_{33}-resonance are the only stable states for irreducible representations j=3/2 and j=2. Unphysical tower of states l_{spin} =l_{isospin} is, therefore, terminated by choosing the appropriate SU(2) representations. 4.Higher spin l> 1/2 quantum states are not "spherically symmetric". The Hamiltonian density function depends on the polar angle theta. 5.Each of the spin-isospin state yields the different range of realizable values of the parameter e. 6.A very good agreement with experimental data is obtained for axial coupling constant g_A in higher representations of SU(2), the problem being previously unsolved by using various extensions of the model in the fundamental representation of SU(2). 7.The basic quantum Skyrme model provides considerable improvements in nucleon magnetic momenta and, especially, in neutron charge density distribution.

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A. Acus, E. Norvaisas. 1999-01-07. Barions as Solitons in Quantum SU(2) Skyrme Model. https://arxiv.org/abs/hep-ph/9901240

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