Leading logarithms in N-flavour mesonic Chiral Perturbation Theory

Summary, in English

We extend earlier work on leading logarithms in the massive nonlinear O(n) sigma model to the case of SU(N) x SU(N)/SU(N) which coincides with mesonic Chiral Perturbation Theory for N flavours of light quarks. We discuss the leading logarithms for the mass and decay constant to six loops and for the vacuum expectation value ((q) over barq) to seven loops. For dynamical quantities the expressions grow extremely large much faster such that we only quote the leading logarithms to five loops for the vector and scalar form factor and for meson-meson scattering. The last quantity we consider is the vector-vector to meson-meson amplitude where we quote results up to four loops for a subset of quantities, in particular for the pion polarizabilities. As a side result we provide an elementary proof that the factors of N appearing at each loop order are odd or even depending on the order and the remaining traces over external flavours. (C) 2013 Published by Elsevier B.V.

• Author: Johan Bijnens; Karol Kampf; Stefan Lanz
• Department/s: Theoretical Particle Physics - Has been reorganised
• Publishing year: 2013
• Language: English
• Pages: 137-164
• Publication/Series: Nuclear Physics, Section B
• Volume: 873
• Issue: 1
• Links: http://dx.doi.org/10.1016/j.nuclphysb.2013.04.012
• Document type: Journal article
• Publisher: North-Holland
• Topic: Subatomic Physics
• Keywords: Renormalization group evolution of parameters; Spontaneous and radiative; symmetry breaking; Chiral Lagrangians; Meson-meson interactions
• Status: Published
• ISBN/ISSN/Other: ISSN: 0550-3213