Linear Collider Test of a Neutrinoless Double Beta Decay Mechanism in   left-right Symmetric Theories
  There are various diagrams leading to neutrinoless double beta decay in left-right symmetric theories based on the gauge group SU(2)_L x SU(2)_R. All can in principle be tested at a linear collider running in electron-electron mode. We argue that the so-called lambda-diagram is the most promising one. Taking the current limit on this diagram from double beta decay experiments, we evaluate the relevant cross section e e to W_L W_R, where W_L is the Standard Model W-boson and W_R the one from SU(2)_R. It is observable if the life-time of double beta decay and the mass of the W_R are close to current limits. Beam polarization effects and the high-energy behaviour of the cross section are also analyzed. 
James Barry, Luis Dorame, Werner Rodejohann
hep-ph