(Seamless, Niobium Coated Copper Cavities for SRF accelerators) LOC's -Biased deposition of Nb-on-Electro-Hydro-Formed-Cu cavities for SRF accelerators

The DOE High Energy Physics (HEP) program seeks to develop advanced accelerator technologies that reduce overall machine size and cost, and also to develop new concepts and capabilities that further scientific and commercial goals beyond HEP’s discovery science mission. Superconducting Radiofrequency ccelerators consume much less power than room temperature accelerators, so can one day replace larger accelerators used in medicine and industry. Breakthroughs are needed, such as replacement of costly bulk niobium cavities by cheaper copper cavities that have a skin of niobium or higher temperature superconductors that reduce cryogenic costs. Statement of how this Problem or Situation is Being Addressed – Alameda Applied Sciences Corporation (AASC) has coated copper cavities with Nb but tests at Jefferson National Accelerator Facility (JLab) and at Los Alamos National Laboratory (LANL) showed that their superconducting performance was deficient, due most likely to the poor quality of the interior surface of the cavities before coating. In this project we will use cavities produced in a single piece via ElectroHydroForming (EHF). These cavities lack the interior weld seam of traditionally manufactured cavities and will be able to attain the desired interior surface figure without the need for expensive and time-consuming steps such as centrifugal barrel polishing and extensive electro-polishing. The seamless cavity with superior surface quality will improve the RF performance of AASC’s superconducting coatings, enhancing their application to SRF technology and leading to commercially available niobium-clad bulk copper SRF cavities. Commercial Applications and Other Benefits – Various governments alone are expected to invest $1B over the next decade or so into superconducting accelerators. Private sector investment would match or exceed that with breakthroughs. AASC would license its knowhow and patents to larger companies so as to have an impact on this opportunity. Key Words – superconducting radiofrequency accelerators, thin film superconductors