  First, we present a simple confining abelian pure gauge theory. Classically,
its kinetic term is not positive definite, and it contains a simple UV
regularized F^4 interaction. This provoques the formation of a condensate ~ F^2
such that, at the saddle point of the effective potential, the wave function
normalization constant of the abelian gauge fields vanishes exactly. Then we
study SU(2) pure Yang-Mills theory in an abelian gauge and introduce an
additional auxiliary field for a BRST invariant condensate of dimension 2,
which renders the charged sector massive. Under simple assumptions its
effective low energy theory reduces to the confining abelian model discussed
before, and the vev of rho is seen to scale correctly with the renormalization
point. Under these assumptions, the confinement condition Z_eff = 0 also holds
for the massive charged sector, which suppresses the couplings of the charged
fields to the abelian gauge bosons in the infrared regime.
