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Cornell physicists, working with Brookhaven National Lab, are developing a new type of particle accelerator called CBETA. This Energy Recovery Linac (ERL) is funded by the National Science Foundation, the Department of Energy, and New York State to create a test accelerator built with permanent magnets as well as electro magnets.

Cornell University has prototyped technology essential for CBETA, including a DC gun and an SRF injector Linac with world-record current and normalized brightness in a bunch train, a high-current CW cryomodule for 70 MeV energy gain, a high-power beam stop, and several diagnostics tools for high-current and high-brightness beams, e.g. a beamline for measuring 6-D phase-space densities, a fast wire scanner for beam profiles, and beam loss diagnostics. All these are now available to equip a one-cryomodule ERL and will be utilized for CBETA.

Within the next several years, CBETA will develop into a powerhouse of accelerator physics and technology, and will be one of the most advanced on the planet (earth). When this prototype ERL is complete and expanded upon, it will be a critical resource to New York State, the nation, and the world, propelling science, biomedical advancement and economic development.

How it works: CBETA will recirculate multiple beams of different energies around the accelerator at one time. The electrons will make four accelerating passes around the accelerator, while building up energy as they pass through the cryomodule. In four more passes, they will return to the superconducting cavities that accelerated them and return their energy back to these cavities - hence it is an Energy Recovery Linac (ERL). While this method conserves energy, it also creates beams that are tightly bound and are a factor of 1,000 times brighter and more coherent than current sources. For more details, please contact the Cornell PI Prof. Hoffstaetter.