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.
last update : 10-21 00:00:00-2005 (827)
With the emergence of projects with large-scale accelerating cavities or even complete cryomodules (e.g. Spiral 2 and XFEL), there has been an increasing need for large surface preparation and clean room assembly facilities.
Learning more about the properties of neutrinos is one of the great challenges in modern-day physics. Physicists are investigating new neutrino sources, based on particle accelerators, to produce neutrino beams that are more intense and better defined in terms of energy and flavor. These sources are known by different names, according to the parent particles concerned. Thus superbeams involve pion decay, neutrino factories concern muon decay, and beta beams radioactive ion decay.
Development of the instrumentation and radio frequency components (RF) covers everything that concerns RF supply, beam measurements (beam position monitor, beam profile monitors…), tuning rings, as well as the design and incorporation of the cavity fittings, such as the couplers that inject the radio frequency wave and the cold tuning systems. At the same time it must make allowance for environmental constraints (i.e. radio frequency, heat and radiation).
The high-intensity light ion source, Silhi, developed as part of the Iphi project, has demonstrated its efficiency for producing intense proton (H+) beams with good qualities and a long lifetime. For example, the source operated for 160 hours at 100 mA with a 99.9% availability, thus proving its reliability, which is one of the main objectives of the Iphi project. Encouraged by this performance, we developed two new sources based on the same principle: the plasma is generated by electron cyclotron resonance (ECR) at a 2.45 GHz radio frequency.
Accelerator instrumentation refers to all the sensors installed in an accelerator to provide information on its operating status and to tune it. Two of the main applications are beam diagnostics − position and profile monitors in particular − and low-level radiofrequency sensors to tune the field of accelerating cavities powered by RF power supplies. IRFU's SIS and SEDI departments are particularly involved in R&D on this area.
Beam dynamics involves studying the motion of a great number of charged particles in static or non-static electromagnetic fields. These fields may be external or induced by particle distribution. At high energy, the effect of synchrotron radiation must be considered. Once the transport optics has been defined to meet accelerator or transfer line specifications, many problems must be overcome to guarantee accurate modeling of beam dynamics. Examples on the fundamental level include the following phenomena: interaction with the residual gas, interaction with solid interfaces, the dynamics of ion source plasmas, beam optics in the presence of high-order electromagnetic elements (hexapoles, ... More »
R&D in this area seeks to improve the performance of niobium accelerating cavities. They are qualified by two figures of merit: the accelerating field, Eacc, and the quality factor, Q0, which is inversely proportional to the surface resistance. Shorter structures can be obtained by increasing Eacc, and cryogenic cooling requirements can be reduced by increasing Q0. So far, accelerating fields in the region of 40 MV/m have been obtained with a quality factor of about 1010, but only with bulk niobium, electropolished, baked cavities. Additional facilities for studying surfaces and superconductivity are now available in completion to ongoing experiments to optimize electropolishing and ... More »