Figure 4

Figure 4: The compactness of a stable boson star (black solid line) as a function of the adimensional self-interaction parameter Λ ≡ λ ∕(4π Gm2 ). The compactness is shown for the most massive stable star (the most compact BS is unstable). This compactness asymptotes for Λ → ∞ to the value indicated by the red, dashed line. Also shown for comparison is the compactness of a Schwarzschild BH (green dot-dashed line), and the maximum compactness of a non-spinning neutron star (blue dotted line). Reprinted with permission from [8]; copyright by IOP.