Browsing by Author "Hadjiyiannakou, Kyriakos"

Now showing items 21-30 of 30

    • Conference Object  

      Nucleon spin and quark content at the physical point 

      Alexandrou, Constantia; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Kallidonis, Christos; Koutsou, Giannis; Jansen, K.; Wiese, C.; Avilés-Casco, A. V. (Proceedings of Science (PoS), 2016)
      We present results on the spin and quark content of the nucleon using Nf =2 twisted mass cloverimproved fermion simulations with a pion mass close to its physical value. We use recently developed methods to obtain accurate ...
    • Article  

      Nucleon structure using lattice QCD 

      Alexandrou, Constantia; Constantinou, Martha; Drach, V.; Hadjiyiannakou, Kyriakos; Jansen, K.; Kallidonis, Christos; Koutsou, Giannis; Leontiou, Theodoros; Vaquero, A. (2013)
      A review of recent nucleon structure calculations within lattice QCD is presented. The nucleon excited states, the axial charge, the isovector momentum fraction and helicity distribution are discussed, assessing the methods ...
    • Conference Object  

      Parton distributions from lattice QCD with momentum smearing 

      Alexandrou, Constantia; Cichy, K.; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Jansen, K.; Steffens, F.; Wiese, C. (Proceedings of Science (PoS), 2016)
      In this work we continue our effort to explore a recent proposal, which allows light-cone distributions to be extracted from purely spatial correlations, being thus accessible to lattice methods. In order to test the ...
    • 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 ...
    • Conference Object  

      Recent results for the proton spin decomposition from lattice QCD 

      Alexandrou, Constantia; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Kallidonis, Christos; Koutsou, Giannis; Jansen, K.; Panagopoulos, Haralambos G.; Steffens, F.; Vaquero, A.; Wiese, C. (Proceedings of Science (PoS), 2016)
      The exact decomposition of the proton spin has been a much debated topic, on the experimental as well as the theoretical side. In this talk we would like to report on recent non-perturbative results and ongoing efforts to ...
    • 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 ...
    • Article  

      A stochastic method for computing hadronic matrix elements 

      Alexandrou, Constantia; Constantinou, Martha; Dinter, S.; Drach, V.; Jansen, K.; Hadjiyiannakou, Kyriakos; Renner, D. B. (2014)
      We present a stochastic method for the calculation of baryon three-point functions that is more versatile than the typically used sequential method. We analyze the scaling of the error of the stochastically evaluated ...
    • Article  

      Strangeness of the nucleon from lattice QCD 

      Alexandrou, Constantia; Constantinou, Martha; Dinter, S.; Drach, V.; Hadjiyiannakou, Kyriakos; Jansen, K.; Koutsou, Giannis; Vaquero, A. (2015)
      We present a nonperturbative calculation of the strangeness of the nucleon yN within the framework of lattice QCD. This observable is known to be an important cornerstone to interpret results from direct dark matter detection ...
    • Article  

      Updated lattice results for parton distributions 

      Alexandrou, Constantia; Cichy, K.; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Jansen, K.; Steffens, F.; Wiese, C. (2017)
      We provide an analysis of the x dependence of the bare unpolarized, helicity, and transversity isovector parton distribution functions (PDFs) from lattice calculations employing (maximally) twisted mass fermions. The x ...