The technology of using ac dipole to achieve long lasting large coherent betatron oscillation has been proved in various accelerators at BNL and FNAL. Various beam experiments of applying ac dipole have performed with very encouraging results. Hence, ac dipole will be a useful device for beam diagnostics. A collaboration is formed between FNAL, UT Austin, BNL and CERN to focus on the conceptual design of ac dipole design.
