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arXiv · hep-ph/9910537

Paramagnetic effect of light quark loops on Chiral Symmetry Breaking

Sebastien Descotes·Luca Girlanda·Jan Stern
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Abstract

We argue that light quark loops produce a paramagnetic suppression of infrared-sensitive order parameters such as , as the number N_f of light fermions increases. The possibly strong dependence of 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.

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Sebastien Descotes, Luca Girlanda, Jan Stern. 1999-10-28. Paramagnetic effect of light quark loops on Chiral Symmetry Breaking. https://doi.org/10.1088/1126-6708%2F2000%2F01%2F041

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