Browsing by Author "Leontiou, Theodoros"
Now showing items 19 of 9

Article
Axial nucleon and nucleon to Δ form factors and the GoldbergerTreiman relations from lattice QCD
Alexandrou, Constantia; Koutsou, Giannis; Leontiou, Theodoros; Negele, J. W.; Tsapalis, Antonios (2007)We evaluate the nucleon axial form factor, GA(q2), and induced pseudoscalar form factor, Gp(q2), as well as the pionnucleon form factor, GπNN(q2), in lattice QCD. We also evaluate the corresponding nucleon to Δ transition ...

Article
Erratum: Axial nucleon and nucleon to Δ form factors and the GoldbergerTreiman relations from lattice QCD (Phys. Rev. D (2007) 76 (094511))
Alexandrou, Constantia; Koutsou, Giannis; Leontiou, Theodoros; Negele, J. W.; Tsapalis, Antonios (2009)

Conference Object
Importance of closed quark loops for lattice QCD studies of tetraquarks
Berlin, J.; AbdelRehim, A.; Alexandrou, Constantia; Brida, M. D.; Finkenrath, J.; Gravina, M.; Leontiou, Theodoros; Wagner, M. (Proceedings of Science (PoS), 2016)To investigate the light scalar tetraquark candidate a0(980) (quantum numbers JP =0+), a correlation matrix including a variety of two and fourquark interpolating operators has to be computed. We discuss efficient ...

Article
NtoΔ axial transition form factors from lattice QCD
Alexandrou, Constantia; Leontiou, Theodoros; Negele, J. W.; Tsapalis, Antonios (2007)We evaluate the N to Δ axial transition form factors in lattice QCD with no dynamical sea quarks, with two degenerate flavors of dynamical Wilson quarks, and using domain wall valence fermions with three flavors of staggered ...

Article
Novel analysis method for excited states in lattice QCD: The nucleon case
Alexandrou, Constantia; Leontiou, Theodoros; Papanicolas, Costas N.; Stiliaris, Efstathios (2015)We employ a novel method to analyze Euclidean correlation functions entering the calculation of hadron energies in lattice QCD. The method is based on the sampling of all possible solutions allowed by the spectral decomposition ...

Article
Nucleon excited states in N f = 2 lattice QCD
Alexandrou, Constantia; Korzec, T.; Koutsou, Giannis; Leontiou, Theodoros (2014)We investigate the excited states of the nucleon using Nf=2 twisted mass gauge configurations with pion masses in the range of about 270 to 450 MeV and one ensemble of Nf=2 Clover fermions at almost physical pion mass. We ...

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
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 ...

Article
Δbaryon electromagnetic form factors in lattice QCD
Alexandrou, Constantia; Korzec, T.; Koutsou, Giannis; Leontiou, Theodoros; Lorcé, C.; Negele, J. W.; Pascalutsa, V.; Tsapalis, Antonios; Vanderhaeghen, M. (2009)We develop techniques to calculate the four Δ electromagnetic form factors using lattice QCD, with particular emphasis on the subdominant electric quadrupole form factor that probes deformation of the Δ. Results are presented ...