With a newly derived equation of state (EOS) of dense matter, we construct zero-temperature compact-star models in hydrostatic equilibrium, for central densities 1.0 ≤ ρc/ρN ≤ 10.0 (ρN = 2.575 × 1014 g cm-3 is the nuclear saturation density). Based on Skyrme's concept of baryons as solitons (of finite extent) in the meson field, the new EOS represents a fluid of Skyrmions coupled to a dilaton field (associated with the glueball of quantum chromodynamics) and a vector meson field (coupled to the baryon number). We find stable configurations to exist for ρc/ρN ≤ 5.0, and they are mostly fluid (the Skyrmion fluid); we thus name them "Skyrmion stars." The outer region of the star (the crust, for densities below the nuclear saturation density) is constructed using the EOS of Baym, Pethick, and Sutherland and accounts on average for 15% of the total mass of the star. Their masses and radii are 0.5 ≤ M/M☉ ≤ 2.95 and 11.0 km ≤ R ≤ 15.3 km, respectively. The new EOS describes a fluid of Skyrmions with a unique behavior at high densities. The Skyrmions shrink as the density increases, allowing for a high compression of matter near the core of the star and thus greater gravitational binding energy. The heaviest stars, which can then withstand greater centrifugal forces, are expected to rotate the fastest in our model. Much of this interesting behavior is inherent in the glueball potential, with its negative contribution to the pressure acting to bind the system; the Skyrmion responds in a nonlinear fashion by shrinking (a result of Skyrmions having structure). Skyrmion stars are fundamentally different from quark stars; the quark degrees of freedom are integrated out, leaving only meson degrees of freedom. Furthermore, unlike boson/soliton stars where the soliton describes the global structure of the star, Skyrmion stars can be looked at as being made of fermionic soliton objects.
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