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Strangeness Equilibration at GSI Energies

G. E. Brown·Mannque Rho·Chaejun Song
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Abstract

We develop the notion of "broad-band equilibration" in heavy-ion processes involving dense medium. Given density-dependent \Km-masses we show that the equilibration at GSI energies claimed to hold in previous treatments down to $\sim ρ_0/4$, can be replaced by a broad-band equilibration in which the \Km-meson and hyperons are produced in an essentially constant ratio independent of density. There are experimental indications that this also holds for AGS energies. We then proceed to argue that {\it both} $K^+$ and $K^-$ must get lighter in dense medium at some density $ρ>ρ_0$ due to the decoupling of the vector mesons. As a consequence, kaon condensation in compact stars could take place {\it before} chiral restoration since the sum of bare quark masses in the kaon should lie below $μ_e$. Another consequence of the decoupling vector interactions is that the quasi-particle picture involving (quasi)quarks, presumably ineffective at low densities, becomes more appropriate at higher densities as chiral restoration is approached.

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G. E. Brown, Mannque Rho, Chaejun Song. 2000-11-01. Strangeness Equilibration at GSI Energies. https://doi.org/10.1016/s0375-9474(01)00942-3

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