TY - JOUR

T1 - Sp (4) gauge theories on the lattice

T2 - Quenched fundamental and antisymmetric fermions

AU - Bennett, Ed

AU - Hong, Deog Ki

AU - Lee, Jong Wan

AU - Lin, C. J.David

AU - Lucini, Biagio

AU - Mesiti, Michele

AU - Piai, Maurizio

AU - Rantaharju, Jarno

AU - Vadacchino, Davide

PY - 2020/4/1

Y1 - 2020/4/1

N2 - We perform lattice studies of meson mass spectra and decay constants of the Sp(4) gauge theory in the quenched approximation. We consider two species of (Dirac) fermions as matter field content, transforming in the 2-index antisymmetric and the fundamental representation of the gauge group, respectively. All matter fields are formulated as Wilson fermions. We extrapolate to the continuum and massless limits and compare to each other the results obtained for the two species of mesons. In the case of two fundamental and three antisymmetric fermions, the long-distance dynamics is relevant for composite Higgs models. This is the first lattice study of this class of theories. The global SU(4)×SU(6) symmetry is broken to the Sp(4)×SO(6) subgroup, and the condensates align with the explicit mass terms present in the lattice formulation of the theory. The main results of our quenched calculations are that, with fermions in the 2-index antisymmetric representation of the group, the masses squared and decay constant squared of all the mesons we considered are larger than the corresponding quantities for the fundamental representation, by factors that vary between ∼1.2 and ∼2.7. We also present technical results that will be useful for future lattice investigations of dynamical simulations, of composite chimera baryons, and of the approach to large N in the Sp(2N) theories considered. We briefly discuss their high-temperature behavior, where symmetry restoration and enhancement are expected.

AB - We perform lattice studies of meson mass spectra and decay constants of the Sp(4) gauge theory in the quenched approximation. We consider two species of (Dirac) fermions as matter field content, transforming in the 2-index antisymmetric and the fundamental representation of the gauge group, respectively. All matter fields are formulated as Wilson fermions. We extrapolate to the continuum and massless limits and compare to each other the results obtained for the two species of mesons. In the case of two fundamental and three antisymmetric fermions, the long-distance dynamics is relevant for composite Higgs models. This is the first lattice study of this class of theories. The global SU(4)×SU(6) symmetry is broken to the Sp(4)×SO(6) subgroup, and the condensates align with the explicit mass terms present in the lattice formulation of the theory. The main results of our quenched calculations are that, with fermions in the 2-index antisymmetric representation of the group, the masses squared and decay constant squared of all the mesons we considered are larger than the corresponding quantities for the fundamental representation, by factors that vary between ∼1.2 and ∼2.7. We also present technical results that will be useful for future lattice investigations of dynamical simulations, of composite chimera baryons, and of the approach to large N in the Sp(2N) theories considered. We briefly discuss their high-temperature behavior, where symmetry restoration and enhancement are expected.

UR - http://www.scopus.com/inward/record.url?scp=85084595959&partnerID=8YFLogxK

U2 - 10.1103/PhysRevD.101.074516

DO - 10.1103/PhysRevD.101.074516

M3 - Article

AN - SCOPUS:85084595959

VL - 101

JO - Physical Review D

JF - Physical Review D

SN - 2470-0010

IS - 7

M1 - 074516

ER -