Browsing by Author "Allés, B."

Now showing items 1-13 of 13

    • Article  

      The 3-loop beta function of QCD 

      Allés, B.; Christou, Chris; Feo, A.; Panagopoulos, Haralambos G.; Vicari, E. (1997)
      Using the background field technique, we calculate the 3-loop beta function of lattice SU (N) gauge theories. In the pure gluonic case, we present our results, comparing to those recently obtained by Luescher and Weisz. ...
    • Article  

      Asymptotic scaling corrections in QCD with Wilson fermions from the 3-loop average plaquette 

      Allés, B.; Feo, A.; Panagopoulos, Haralambos G. (1998)
      We calculate the 3-loop perturbative expansion of the average plaquette in lattice QCD with Nf massive Wilson fermions and gauge group SU(N). The corrections to asymptotic scaling in the corresponding energy scheme are ...
    • Article  

      Erratum: Asymptotic scaling corrections in QCD with Wilson fermions from the 3-loop average plaquette (Physics Letters, Section B: Nuclear, Elementary Particle (1998) 426 (361)) 

      Allés, B.; Feo, A.; Panagopoulos, Haralambos G. (2003)
    • Article  

      Lattice multiplicative renormalization beyond 1-loop 

      Allés, B.; Campostrini, M.; Feo, A.; Panagopoulos, Haralambos G. (1994)
      This is a progress report on a computational scheme for the perturbative evaluation of lattice renormalization functions. This scheme, implemented as a package on a symbolic manipulation computer language, has already ...
    • Article  

      Lattice perturbation theory by computer algebra: A three-loop result for the topological susceptibility 

      Allés, B.; Campostrini, M.; Feo, A.; Panagopoulos, Haralambos G. (1994)
      We present a scheme for the analytic computation of renormalization functions on the lattice, using a symbolic manipulation computer language. Our first nontrivial application is a new three-loop result for the topological ...
    • Article  

      The proton matrix element of the topological charge in quenched QCD 

      Allés, B.; Campostrini, M.; Del Debbio, L.; Di Giacomo, A.; Panagopoulos, Haralambos G.; Vicari, E. (1994)
      We compute on the lattice the on-shell proton matrix element of the topological charge density in the quenched approximation. Our calculation makes use of a nonperturbative means of determining the multiplicative renormalization ...
    • Article  

      Status of αs determinations from the non-perturbatively renormalised three-gluon vertex 

      Parrinello, C.; Richards, D. G.; Allés, B.; Panagopoulos, Haralambos G.; Pittori, C. (1998)
      We demonstrate the feasibility of computing α, from the lattice three-gluon vertex in the Landau gauge. Data from 164 and 244 quenched lattices at β = 6.0 are presented. Our main result is that 2-loop asymptotic scaling ...
    • Article  

      The three-loop lattice free energy 

      Allés, B.; Campostrini, M.; Feo, A.; Panagopoulos, Haralambos G. (1994)
      We calculate the free energy of SU(N) gauge theories on the lattice, to three loops. Our result, combined with Monte Carlo data for the average plaquette, gives a more precise estimate of the gluonic condensate. © 1994.
    • Article  

      Three-loop results in QCD with Wilson fermions 

      Allés, B.; Christou, Chris; Feo, A.; Panagopoulos, Haralambos G.; Vicari, E. (1998)
      We calculate the third coefficient of the lattice beta function in QCD with Wilson fermions, extending the pure gauge results of Lüscher and Weisz
    • Article  

      Three-loop results on the lattice 

      Allés, B.; Campostrini, M.; Feo, A.; Panagopoulos, Haralambos G. (1993)
      We present some new three-loop results in lattice gauge theories, for the Free Energy and for the Topological Susceptibility. These results are an outcome of a scheme which we are developing (using a symbolic manipulation ...
    • Article  

      The three-loop β function in SU(N) lattice gauge theories 

      Allés, B.; Feo, A.; Panagopoulos, Haralambos G. (1997)
      We calculate the third coefficient of the lattice β function in pure Yang-Mills theory. We make use of a computer code for solving perturbation theory analytically on the lattice. We compute the divergent integrals by using ...
    • Article  

      Topological charge density renormalization in the presence of dynamical fermions 

      Allés, B.; Di Giacomo, A.; Panagopoulos, Haralambos G.; Vicari, E. (1995)
      We study the renormalization group behaviour of the topological charge density in full QCD on the lattice. We propose a way of extracting the necessary renormalization functions from Monte Carlo simulations. © 1995.
    • Article  

      αs from the non-perturbatively renormalised lattice three-gluon vertex 

      Allés, B.; Henty, D. S.; Panagopoulos, Haralambos G.; Parrinello, C.; Pittori, C.; Richards, D. G. (1997)
      We compute the running QCD coupling on the lattice by evaluating two-point and three-point off-shell gluon Green's functions in a fixed gauge and imposing non-perturbative renormalisation conditions on them. Our exploratory ...