Scaling limits at q → 1 of the elliptic vertex algebras A q,p ( sl(N ) c ) are defined for any N , extending the previously known case of N = 2. They realise deformed, centrally extended double Yangian structures DY r (sl(N )) c . As in the quantum affine algebras U q ( sl(N ) c ), and quantum elliptic affine algebras A q,p ( sl(N ) c ), these algebras contain subalgebras at critical values of the central charge c = −N − M r (M integer, 2r = ln p/ ln q), which become Abelian when c = −N or 2r = N h for h integer. Poisson structures and quantum exchange relations are derived for their abstract generators.
MSC number: 81R50, 17B37LAPTH-716/99 PAR-LPTHE 99-05 DTP-99-7 math.QA/9905100