Behaviour of the topological susceptibility in two colour QCD across the finite density transition

The behaviour of the topological susceptibility chi in QCD with two colours and 8 flavours of quarks is studied at nonzero temperature on the lattice across the finite density transition. It is shown that the signal of chi drops abruptly at a critical chemical potential mu_c, much as it happens at the finite temperature and zero density transition. The Polyakov loop and the chiral condensate undergo their transitions at the same critical value mu_c. At a value mu_s of the chemical potential, called saturation point, which in our case satisfies mu_s > mu_c, Pauli blocking supervenes and consequently the theory becomes quenched.