Stabilization of the linear SU(2) Nambu-Jona-Lasinio soliton via vector mesons

The solitonic sector of the SU(2) NJL model with σ, π ρ A1 and ω mesons is investigated. the scalar and pseudo-scalar meson fields are not constrained to the chiral circle condition, i.e. σ2(r) + ''pi''2(r) ''no='' fπ2. We show numerically that the repulsive ω meson prevents the recently discovered collapse of the hedgehog soliton. A comparison of the linear and the nonlinear NJL model leads to similar solitonic properties, although the deviations from the chiral circle condition are found not to be small. (Author)