A rational approximation to ⟨VV-AA⟩ and its O(p6) low-energy constant

Using a sequence of rational approximants and the large-N-C limit of QCD, we estimate the value of the low-energy constant C-87 which appears in the Lagrangian of Chiral Perturbation Theory at O(p(6)). (C) 2008 Elsevier B.V. All rights reserved.