Even Grassmann fields in momentum space

We extend previous results about fields whose Fourier components are even elements of a Grassmann algebra. Their main interest is related to the possibility that they describe fermionic composites. We evaluate the free propagators for arbitrary index of nilpotency and investigate to one loop a φ⁴ model. Due to the nature of the integral over even Grassmann fields such a model exists for repulsive as well as attractive selfinteraction. In the first case the β-function is equal to that of the ordinary theory while in the second one the model is asymptotically free. The renormalized mass has a peculiar dependence on the cut off, being quadratically increasing/decreasing for attractive/repulsive selfinteraction.