Consensus Report of a Workshop on "Matrix elements for Neutrinoless Double Beta Decay"

This is the consensus of a Workshop on “Matrix elements for Neutrinoless Double Beta Decay” held at the IPPP Durham (UK). The aim of this workshop has been to define a well planned, coherent strategy to reduce the errors on nuclear matrix element calculations for double beta decay to a level of 30% by performing the necessary measurements with currently existing and planned facilities. These measurements should provide reliable input for the theoretical calculations. The outcome of the workshop has been organised in working packages. The consensus might act as a starting point for an international coherent effort to achieve this goal.