Strange baryonic matter from chiral effective Lagrangians

We investigate the existence of bound states of baryons in a kaon condensate using chiral mean field theory based on an effective SU(3)(L) x SU(3)(R) chiral Lagrangian with next to leading order terms (n = 2, 3, 4). We search for infinite baryon number solutions, namely ''strange baryonic matter''. using a Thomas-Fermi and the lowest order Hartree approximations. For simplicity we study a pure K-0-condensate and only neutrons, the lightest baryons in that condensate. We find solutions with neutron number densities, rho(n) greater than or similar to 3.5 rho(0), where rho(0) is the infinite nuclear matter density. This is consistent with the estimate of the onset of a K-condensate at rho(n) similar or equal to 2-4 rho(0). We show that the binding energies, E-b, grow with rho(n) and for rho(n) < 7 rho(0) (at rho(n) greater than or similar to 7 rho(0) perturbative expansion is lost) we find E-b < 150 MeV (E-b < 70 MeV for rho(n) < 5 rho(0)) even in the most favorable cases. These binding energies may be too low for this type of matter to appear and persist in the early Universe. (C) 1997 Published by Elsevier Science B.V.