Browsing by Subject "Lattice theory"

Now showing items 21-29 of 29

    • Conference Object  

      PLQCD library for lattice QCD on multi-core machines 

      Abdel-Rehim, A.; Alexandrou, Constantia; Anastopoulos, Nikos; Koutsou, Giannis; Liabotis, A. Ioannis; Papadopoulou, Nikela (Proceedings of Science (PoS), 2013)
      PLQCD is a stand-alone software library developed under PRACE for lattice QCD. It provides an implementation of the Dirac operator for Wilson type fermions and few efficient linear solvers. The library is optimized for ...
    • Conference Object  

      The quark contents of the nucleon and their implication for dark matter search 

      Alexandrou, Constantia; Constantinou, Martha; Drach, V.; Hadjiyiannakou, Kyriakos; Jansen, K.; Koutsou, Giannis; Strelchenko, A.; Vaquero, A. (Proceedings of Science (PoS), 2013)
      We present results concerning the light and strange quark contents of the nucleon using Nf = 2+1+1 flavours of maximally twisted mass fermions. The corresponding σ- Terms are casting light on the origin of the nucleon mass ...
    • Conference Object  

      A QUDA-branch to compute disconnected diagrams in GPUs 

      Alexandrou, Constantia; Hadjiyiannakou, Kyriakos; Koutsou, Giannis; Strelchenko, A.; Avilés-Casco, A. V. (Proceedings of Science (PoS), 2013)
      Although QUDA allows for an efficient computation of many QCD quantities, it is surprinsingly lacking tools to evaluate disconnected diagrams, for which GPUS are specially well suited. We aim to fill this gap by creating ...
    • Article  

      Renormalization and mixing in lattice QCD: The case of the chromomagnetic operator 

      Constantinou, Martha G.; Costa, M. G.; Frezzotti, R.; Lubicz, V.; Martinelli, G.; Meloni, D.; Panagopoulos, Haralambos G.; Simula, S. (2014)
      We study matrix elements of the "chromomagnetic" operator on the lattice. This operator is contained in the strangeness-changing effective Hamiltonian which describes electroweak effects in the Standard Model and beyond. ...
    • Conference Object  

      Sigma- Terms and axial charges for hyperons and charmed baryons 

      Alexandrou, Constantia; Hadjiyiannakou, Kyriakos; Jansen, K.; Kallidonis, Christos (Proceedings of Science (PoS), 2013)
      We present results for the s- Terms and axial charges for various hyperons and charmed baryons using Nf = 2+1+1 twisted mass fermions. For the computation of the three-point function we use the fixed current method. For ...
    • Conference Object  

      Study of the a0(980) on the lattice 

      Wagner, M.; Abdel-Rehim, A.; Alexandrou, Constantia; Gravina, M.; Koutsou, Giannis; Brida, M. D.; Scorzato, L.; Urbach, C. (Proceedings of Science (PoS), 2013)
      We present lattice results for the a0(980) state using a variational approach with a variety of creation operators: quark- Antiquark, mesonic molecule, diquark- Antidiquark as well as two-meson type. Focus is put on recent ...
    • Conference Object  

      A study of the radiative transition ππ → πγ∗ with lattice QCD 

      Petschlies, Marcus; Leskovec, L.; Alexandrou, Constantia; Koutsou, Giannis; Meinel, S.; Negele, J. W.; Paul, S.; Pochinsky, A.; Rendon, G.; Syritsyn, S. (Proceedings of Science (PoS), 2016)
      Lattice QCD calculations of radiative transitions between hadrons have in the past been limited to processes of hadrons stable under the strong interaction. Recently developed methods for 1 → 2 transition matrix elements ...
    • Conference Object  

      Using a new analysis method to extract excited states in the scalar meson sector 

      Finkenrath, J.; Alexandrou, Constantia; Berlin, J.; Brida, M. D.; Leontiou, Theodoros; Wagner, M. (Proceedings of Science (PoS), 2016)
      We explore a method to extract energy eigenstates, called Athens Model Independent Analysis Scheme (AMIAS), which is an alternative to solving standard Generalized Eigenvalue Problems (GEVP). The method is based on ...
    • Conference Object  

      θ Dependence of 4D SU(N) gauge theories at finite temperature 

      Bonati, C.; D'Elia, M.; Panagopoulos, Haralambos G.; Vicari, E. (Proceedings of Science (PoS), 2013)
      We report a study of the dependence of 4D SU(N) gauge theories on the topological θ term at finite temperature, and in particular in the large-N limit. We show that theθ dependence drastically changes across the deconfinement ...