Conveners
SRF: Directions for R&D
- Frank Marhauser (JLAB)
SRF: Cavity technology
- Cristian Pira (LNL-INFN)
SRF: Studies
- Anne-Marie Valente-Feliciano (Jefferson Lab)
SRF: Innovation
- Olivier Brunner (CERN)
The design study for the future circular collider (FCC) includes an electron-positron collider with beam energies ranging from 45.6 to 182.5 GeV in order to study the properties of the Z, W and H bosons and the top quark with high precision. In order to accelerate the particles to the required energy, an RF system is needed to provide the accelerating voltage for the four machine setups....
Superconducting accelerating cavities are the technology of choice for many modern and future particle accelerators. Increasing their efficiency is therefore crucial to minimize the power consumption during their operation and therefore significantly cut the cost and enabling the realization of more powerful machines.
The efficiency of niobium superconducting RF cavities can be maximized in...
Niobium coated copper accelerating cavities have demonstrated their strong potential in accelerators such as LEP, LHC and HIE-ISOLDE and could become a technology of choice for such a machine as the FCC.
On the way of further improving thin-film coated copper cavities performances one proposes to substitute niobium by a superconductor that could lead to a higher quality factor as well as a...
A key challenge for the next accelerators is the cost reduction. Bulk niobium cavities performances are closer to their theoretical limits and an alternative technology is mandatory. Niobium thin film copper cavities are the most explored solution, but the Q-slope problem, characteristic of these resonators, limits the applications where high accelerating fields are requested.
In this work an...
In order to achieve the performance required for the Future Circular Collider (FCC) Superconducting Radio Frequency (SRF) cavities, new superconducting thin films are being investigated. The functionality of the cavities are particularly dependent upon the reliability of these films at the micro and nanoscale. Therefore, in order to gain insight into their characteristics, the advanced...
In the framework of the FCC study, niobium-coated copper cavities are considered to operate at 400 MHz. Electrohydraulic forming (EHF) is a potential alternative to conventional shaping methods of copper half cells, through which geometrical precision, a good repeatability and a reduced spring back can be achieved.
Material characterisation by hardness measurements, Electron Backscatter...
Recently, nitrogen doping (N-doping) technology has been proved to increase Q value of superconducting cavity obviously, which lowers the BCS resistance of Nb. After N-doping, Q of 9-cell 1.3 GHz cavity can be increased to 3E10 at Eacc = 16 MV/m, while 1.5*1010 without N-doping. Since 2013, there have been over 60 cavities nitrogen doped at FNAL, JLAB and Cornell. The Circular Electron...
