THE CORE CHAIN OF CIRCLES OF MASKIT'S EMBEDDING FOR ONCE-PUNCTURED TORUS GROUPS

In this paper, we describe the limit set Lambda(n) of a sequence of manifolds N-n in the boundary of Maskit's embedding of the once- punctured torus. We prove that Lambda(n) contains a chain of tangent circles {C-n,C-j} that are described from the end invariants of the manifold. In particular, we give estimates in terms of n of the radii r(n,j) of the circles and prove that r(n,j) decrease when n tends to infinity. We then apply these results to McShane's identity, to obtain an estimate of the width of the limit set in terms of n.