English

Paramagnetic effect of light quark loops on Chiral Symmetry Breaking

High Energy Physics - Phenomenology 2009-10-31 v1 High Energy Physics - Lattice

Abstract

We argue that light quark loops produce a paramagnetic suppression of infrared-sensitive order parameters such as <qq>, as the number N_f of light fermions increases. The possibly strong dependence of <qq> on N_f is related to the observed Zweig rule violation in the scalar channel. Presuming the existence of a chiral phase transition for not too large N_f, we discuss the phenomenological possibilities of separately determining the two-flavour and three-flavour condensates and the quark mass ratio r=2m_s/(m_u+m_d). The issue is closely related to the interpretation of new forthcoming precise pi-pi data at low energy.

Keywords

Cite

@article{arxiv.hep-ph/9910537,
  title  = {Paramagnetic effect of light quark loops on Chiral Symmetry Breaking},
  author = {Sebastien Descotes and Luca Girlanda and Jan Stern},
  journal= {arXiv preprint arXiv:hep-ph/9910537},
  year   = {2009}
}

Comments

15 pages, Latex, using JHEP.cls (included), 1 PS figure