Eur. Phys. J. C (2005) 41: 535-544
https://doi.org/10.1140/epjc/s2005-02250-9

theoretical physics

Operator product expansion and quark condensate from lattice QCD in coordinate space

¹ Departament de Fisica Teórica and IFIC, Univ. de Valéncia, Dr. Moliner 50, 46100, Burjassot, Valéncia, Spain
² Dipartimento di Fisica, Univ. di Roma Tre, Via della Vasca Navale 84, 00146, Rome, Italy
³ INFN, Sezione di Roma III, Via della Vasca Navale 84, 00146, Rome, Italy
⁴ INFN, Laboratori Nazionali di Frascati, Via E. Fermi 40, 00044, Frascati, Italy
⁵ Dipartimento di Fisica, Univ. di Roma “La Sapienza”, P.le A. Moro 2, 00185, Rome, Italy

Abstract

We present a lattice QCD determination of the chiral quark condensate based on a new method. We extract the quark condensate from the operator product expansion of the quark propagator at short euclidean distances, where it represents the leading contribution in the chiral limit. From this study we obtain , in good agreement with determinations of this quantity based on different approaches. The simulation is performed by using the -improved Wilson action aton a volume 32³ × 70 in the quenched approximation.