Solution of the H+3model on a disc

We determine all the correlators of the H3+ model on a disc with AdS2-braneboundary conditions in terms of correlators of Liouville theory on a disc withFZZT-brane boundary conditions. We argue that the Cardy-Lewellen constraintsare weaker in the H3+ model than in rational conformal field theories due toextra singularities of the correlators, but strong enough to uniquely determinethe bulk two-point function on a disc. We confirm our results by detailedanalyses of the bulk-boundary two-point function and of the boundary two-pointfunction. In particular we find that, although the target space symmetrypreserved by AdS2-branes is the group SL(2,R), the open string states betweentwo distinct parallel AdS2-branes belong to representations of the universalcovering group.Comment: 32 pages, v2: minor change