Asymptotics of multivariate orthogonal polynomials with hyperoctahedral symmetry

We present a formula describing the asymptotics of a class of multivariate orthogonal polynomials with hyperoctahedral symmetry as the degree tends to infinity. The polynomials under consideration are characterized by a factorized weight function satisfying certain analyticity assumptions. As an application, the large-degree asymptotics of the Koornwinder-Macdonald BC_N-type multivariate Askey-Wilson polynomials is determined.