Universality and scaling behavior of RG gauge actions

Abstract We study universality and scaling properties of RG gauge actions (Iwasaki and DBW2). In the first part we consider the critical temperature T c and compute the reference energy scale r 0 for critical couplings β c corresponding to N t =3,4,6,8. The universality of T c r 0 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 T c r 0 =0.7498(50) is extracted. We compute also the glueball masses for the states 0 ++ and 2 ++ , investigate the scaling of m 0 ++ r 0 and m 2 ++ r 0 and point out practical problems which are due to the violation of positivity present in the RG actions.