Hadron spectrum in a two-colour baryon-rich medium

The hadron spectrum of SU(2) lattice gauge theory with two flavours of Wilson quark is studied on an 83×16 lattice using all-to-all propagators, with particular emphasis on the dependence on quark chemical potential μ. As μ is increased from zero the diquark states with non-zero baryon number B respond as expected, while states with B=0 remain unaffected, until the onset of non-zero baryon density at μ=mπ/2. Post onset the pi-meson mass increases in accordance with chiral perturbation theory while the rho becomes lighter. In the diquark sector a Goldstone state associated with a superfluid ground state can be identified. A further consequence of superfluidity is an approximate degeneracy between mesons and baryons with the same spacetime and isospin quantum numbers. Finally we find tentative evidence for the binding of states with kaon quantum numbers within the baryonic medium.