Quantum Solitons with Cylindrical Symmetry

Abstract

Soliton solutions with cylindrical symmetry are investigated within the nonlinear $σ$-model disregarding the Skyrme-stabilization term. The solitons are stabilized by quantization of collective breathing mode and collapse in the $\hbar \to 0$ limit. It is shown that for such stabilization mechanism the model, apart from solitons with integer topological number $B$, admits the solitons with half-odd $B$. The solitons with integer $B$ have standard spin-isospin classification, while $B={\ds {1\over 2}}$ solitons are shown to be characterized by spin, isospin and some additional "momentum".