Division of accelerators, cryogenics and magnetism

Breakthroughs in particle physics are closely related to the availability of electron beams of ever-increasing energy and luminosity. Electron accelerators are also essential to free electron lasers operating in the ultraviolet and X-ray regions. To supply the high brilliance beams used in solid-state physics, as well as in chemistry and biology, 3^rd generation synchrotron radiation machines also operate with very intense electron beams.
 

High-intensity high-energy linear accelerators, capable of consistently reaching 1 GeV and several tens of milliamps, find numerous applications in nuclear and particle physics, and in condensed matter physics as well. The interaction of a proton beam, accelerated by a Linac of this kind, with a target, enables the production of particles such as radioactive ions, neutrons, neutrinos or muons. These particles then form secondary beams, which may be used for example in the transmutation of nuclear waste or for studying the structure of various materials.
These future generation accelerators will apply technologies that are the subject of ongoing R&D programmes at SACM, such as the lphi (Injecteur de protons de haute intensité) project for the low energy part, and the programme for 700 MHz superconducting accelerator cavities for the high-energy part. Knowledge and experience gained in these two areas have enabled SACM to play an important role in the Spiral 2 project, a complete linac designed for the study of a large range of exotic nuclei.

 

Any new project presents challenges of its own and generally needs specific R&D. Conversely, it is often the case that breakthroughs in some one particular R&D can profit to several projects. Several lines of R&D specific to accelerators are pursued at SACM:
• The improvement of analytic models and development of numerical methods for modelling the particle beams dynamics which has to be adjusted to higher and higher requirements for operating parameters (energy, luminosity, reliability, …).
• The development of ion sources based on plasma generated by electron cyclotron resonance for the production of intense H+ and H- ion beams; progress here can result in continuous improvement in intensities and reliability.
• Systematic studies in view of understanding the physical origin of the limits of accelerating field in the superconducting radio frequency cavities, and defining treatment suitable to achieve higher fields. In addition, technological developments allow us to study the construction of complete cryomodules in an accelerator environment, by incorporating superconducting cavities, associated RF components, as well as the supporting instrumentation.