  The effect of changing the lattice action for the gluon field on the recently
observed [1] first order phase transition near zero quark mass is investigated
by replacing the Wilson plaquette action by the DBW2 action. The lattice action
for quarks is unchanged: it is in both cases the original Wilson action. It
turns out that Wilson fermions with the DBW2 gauge action have a phase
structure where the minimal pion mass and the jump of the average plaquette are
decreased, when compared to Wilson fermions with Wilson plaquette action at
similar values of the lattice spacing. Taking the DBW2 gauge action is
advantageous also from the point of view of the computational costs of
numerical simulations.
