Sample Parameters of a Two - Mile

The results derived in Ref. 2 have been used to calculate a sample set of parameters1 for a superconducting version of the two-mile SLAC accelerator. These calculations have been carried out in order to provide a basis for further technical discussions. Beam Energy The energy goal of 100 GeV (10 MeV/ft.) has been chosen since this energy is sufficiently higher than the 20 GeV capability of the present SLAC accelerator to be of great interest in physics research and yet within anticipated fiscal and technical limitations. It should be remarked here that the gradient of 10 MeV/ft. is several times higher than the best gradient achieved to date in a superconducting accelerator. However, superconductivity in its application to accelerators is still in its infancy; therefore, in establishing tentative design parameters for a future accelerator it has been assumed that further advances will make the proposed gradient realistic. Selection of Accelerator Type As noted in Ref. 2, the ratio of peak to average fields in a traveling wave accelerator is significantly less than in a standing wave accelerator (a factor of w 1.6 improvement appears to be achievable). For this reason, the tentative decision has been made to adopt a traveling wave design with RF feedback.