PT Journal
AU Bernardoni, F
   Garron, N
   Hernandez, P
   Necco, S
   Pena, C
TI Probing the chiral regime of N-f=2 QCD with mixed actions
SO Physical Review D
JI Phys. Rev. D
PY 2011
BP 054503
EP 17pp
VL 83
IS 5
DI 10.1103/PhysRevD.83.054503
LA English
AB We report on our first experiences with a mixed action setup with overlap valence quarks and nonperturbatively O(a) improved Wilson sea quarks. For the latter we employ CLS N-f = 2 configurations with light sea-quark masses at small lattice spacings. Exact chiral symmetry allows to consider very light valence quarks and explore the matching to (partially-quenched) Chiral Perturbation Theory (ChPT) in a mixed epsilon/p-regime. We compute the topological susceptibility and the low-lying spectrum of the massless Neuberger-Dirac operator for three values of the sea-quark mass, and compare the sea-quark mass dependence to NLO ChPT in the mixed regime. This provides two different determinations of the chiral condensate, as well as information about some NLOlow-energy couplings. Our results allow to test the consistency of the mixed-regime approach to ChPT, as well as of the mixed action framework.
ER