Deconfinement and chiral symmetry restoration in an SU(3) gauge theory with adjoint fermions

analyze the finite temperature phase diagram of QCD with fermions in the adjoint representation. The simulations performed with four dynamical Majorana fermions show that the deconfinement and chiral phase transitions occur at two distinct temperatures. While the deconfinement transition is first-order at T-d We find evidence for a continuous chiral transition at a higher temperature T-c similar or equal to 8 T-d. We observe a rapid change of bulk thermodynamic observables at T-d which reflects the increase in the number of degrees of freedom. However, these show little variation at T-c, where the fermion condensate vanishes. We also analyze the potential between static fundamental and adjoint charges in all three phases and extract the corresponding screening masses above T-d. (C) 1999 Elsevier Science B.V. All rights reserved.