TY - JOUR

T1 - Non-Abelian gauged Nambu-Jona-Lasinio models on the lattice

AU - Catterall, Simon

AU - Galvez, Richard

AU - Hubisz, Jay

AU - Mehta, Dhagash

AU - Veernala, Aarti

PY - 2012/8/13

Y1 - 2012/8/13

N2 - We use Monte Carlo simulation to probe the phase structure of a SU(2) gauge theory containing N f Dirac fermion flavors transforming in the fundamental representation of the group and interacting through an additional four-fermion term. Pairs of physical flavors are implemented using the two tastes present in a reduced staggered fermion formulation of the theory. The resultant lattice theory is invariant under a set of shift symmetries which correspond to a discrete subgroup of the continuum chiral-flavor symmetry. The pseudoreal character of the representation guarantees that the theory has no sign problem. For the case of N f=4 we observe a crossover in the behavior of the chiral condensate for strong four-fermi coupling associated with the generation of a dynamical mass for the fermions. At weak gauge coupling this crossover is consistent with the usual continuous phase transition seen in the pure (ungauged) Nambu-Jona-Lasinio model. However, if the gauge coupling is strong enough to cause confinement, we observe a much more rapid crossover in the chiral condensate consistent with a first order phase transition.

AB - We use Monte Carlo simulation to probe the phase structure of a SU(2) gauge theory containing N f Dirac fermion flavors transforming in the fundamental representation of the group and interacting through an additional four-fermion term. Pairs of physical flavors are implemented using the two tastes present in a reduced staggered fermion formulation of the theory. The resultant lattice theory is invariant under a set of shift symmetries which correspond to a discrete subgroup of the continuum chiral-flavor symmetry. The pseudoreal character of the representation guarantees that the theory has no sign problem. For the case of N f=4 we observe a crossover in the behavior of the chiral condensate for strong four-fermi coupling associated with the generation of a dynamical mass for the fermions. At weak gauge coupling this crossover is consistent with the usual continuous phase transition seen in the pure (ungauged) Nambu-Jona-Lasinio model. However, if the gauge coupling is strong enough to cause confinement, we observe a much more rapid crossover in the chiral condensate consistent with a first order phase transition.

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U2 - 10.1103/PhysRevD.86.034502

DO - 10.1103/PhysRevD.86.034502

M3 - Article

AN - SCOPUS:84865074122

SN - 1550-7998

VL - 86

JO - Physical Review D - Particles, Fields, Gravitation and Cosmology

JF - Physical Review D - Particles, Fields, Gravitation and Cosmology

IS - 3

M1 - 034502

ER -