The international particle physics community is almost unanimous in its desire for a TeV electron–positron linear collider. Such a facility would be at least 30 km long and cost $5–7 billion. But for more than a decade, competing international collaborations have devoted intensive R&D to two different RF accelerating technologies for the collider (see Physics Today, Physics Today 0031-9228 57 9 2004 49 https://doi.org/10.1063/1.1809092 September 2004, page 49 ). Now, at last, the community has settled on one of the competing technologies.
The International Committee for Future Accelerators has endorsed the recommendation of the 12-member International Technology Recommendation Panel (ITRP) that the RF accelerating cavities be made of superconducting niobium operating at 2 K rather than copper at room temperature (see http://www.ligo.caltech.edu/~skammer/ITRP_Home.htm). Although the superconducting technology was championed by DESY, the German Electron Synchrotron laboratory in Hamburg, the choice does not imply a specific site for the collider,...
