Abstract :
We study universality and scaling properties of RG gauge actions (Iwasaki and DBW2). In the first part we consider the critical temperature Tc and compute the reference energy scale r0 for critical couplings βc corresponding to Nt=3,4,6,8. The universality of Tcr0 between Iwasaki and Wilson action is confirmed and the scaling behavior of the Iwasaki action is found to be better than the one for the Wilson action. The results for the DBW2 action show larger lattice artifacts. A continuum value Tcr0=0.7498(50) is extracted. We compute also the glueball masses for the states 0++ and 2++, investigate the scaling of m0++r0 and m2++r0 and point out practical problems which are due to the violation of positivity present in the RG actions.
