Galactic halos as boson stars

We investigate a boson star with a self-interacting scalar field as a model of galactic halos. The model has slightly increasing rotation curves and allows wider ranges of the mass (m) and coupling (λ) of the halo dark matter particle than the noninteracting model previously suggested. The two quantities are related by ${\lambda }^{1/2}$(${\mathit{m}}_{\mathit{p}}$/m${)}^2$≳${10}^{50}$. © 1996 The American Physical Society.