Kaons and pions in strange quark matter

P. Costa; M. C. Ruivo

doi:doi:10.1209/epl/i2002-00272-8

DOI: 10.1209/epl/i2002-00272-8

Europhys. Lett., 60 (3) , pp. 356-362 (2002)

Kaons and pions in strange quark matter

P. Costa and M. C. Ruivo

Centro de Física Teórica, Departamento de Física, Universidade de Coimbra P-3004-516 Coimbra, Portugal

(Received 23 April 2002; accepted in final form 16 August 2002)

Abstract
The behavior of kaons and pions in strange quark matter in weak equilibrium is investigated within the SU(3) Nambu-Jona-Lasinio (NJL) model. This work focuses a region of high densities where the behavior of mesons has not been explored in the framework of this model. It is found that above the density where strange valence quarks appear in the medium, $\rho=3.8 \rho_0$ , a change of behavior of different observables is observed indicating a tendency to the restoration of flavor symmetry. In particular, the splitting between charge multiplets, K⁺, K^-; K⁰, $\bar{K^0}$ and $\pi^+$ , $\pi^-$ decrease and the low-energy modes with quantum numbers of K^-, $\bar{K^0}$ and $\pi^+$ , which are excitations of the Fermi sea, are less relevant than for lower densities.

PACS
11.30.Rd - Chiral symmetries.
11.55.Hx - Sum rules.
14.40.Aq - $\pi$ , K, and $\eta$ mesons.

© EDP Sciences 2002