A5022656297- Gyrotron and Vacuum Electronics Research
- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Microwave Engineering and Waveguides
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- Wave and Wind Energy Systems
- Electromagnetic Simulation and Numerical Methods
- Advanced Multi-Objective Optimization Algorithms
- Wind Energy Research and Development
- Frequency Control in Power Systems
- Microgrid Control and Optimization
- Maritime Transport Emissions and Efficiency
- Pulsed Power Technology Applications
- Energy Harvesting in Wireless Networks
Cockcroft Institute
2017
Daresbury Laboratory
2017
Lancaster University
2009-2017
In certain high power RF systems multipactor cannot be avoided for all operating points, but its existence places limits on performance, efficiency, lifetime, and reliability. As an example in the input couplers of superconducting cavities can a major limitation to maximum power. Several studies have concentrated rectangular waveguide which are used many light sources. Most these neglect space charge assuming that effect is simply defocus electron bunches. Modelling saturation interest...
Use of a second harmonic and third cavity within klystron to increase efficiency has been studied using particle-in-cell (PIC) code, MAGIC 2D. The six device drive frequency 1GHz, predicted 88%, 39 dB gain an output power 833 kW. preliminary simulation results have revealed indications bunching with bunch core oscillations. initial analysis the F-Tube PIC study are presented.
A 4-rod deflecting structure is proposed as a possible crab cavity design for the LHC high luminosity upgrade. Crab cavities are required upgrade to provide greater bunch overlap in presence of crossing angle, but must fit existing limited space. The has two parallel sections consisting longitudinally opposing quarter-wave rods, where each rod opposite charge from its nearest neighbors. transversely compact because frequency dependent on lengths rather than radius. Simulations were...
The design of klystrons has long been a manual process guided by experience. However, with well-defined specifications and sufficiently rapid simulation methods, it is good candidate for automatic optimization techniques. In this paper, such technique evaluated refined using klystron specific techniques, leading to several designs (with different tradeoffs between efficiency size) each structure comparable the SLAC B-factory klystrons. most efficient which, while only 1% more efficient,...
Upcoming large scale particle accelerators, such as the Future Circular Collider (FCC), Compact Linear (CLIC) and International (ILC) are expected to require RF drive on order of 100 MW. Therefore, efforts improve efficiency specific source is significant interest accelerator community. Klystrons an attractive choice source, with current state art tubes offering efficiencies up 70%. The High Efficiency Klystron Activity (HEIKA) collaboration seeks upon this by considering novel methods...
Six UK institutes are engaged in a collaborative R&D programme with CERN aimed at demonstrating key aspects of technology feasibility for the Compact Linear Collider (CLIC). We give an overview and status of: 1) Drive-beam components: quadrupole magnets beam phase feed-forward prototype. 2) Beam instrumentation: stripline cavity position monitors, electro-optical longitudinal bunch profile monitor, laserwire diffraction transition radiation monitors transverse beam-size determination. 3)...
Concerns over climate change and energy security help motivate research into wave converters (WEC). Two WEC topologies have shown particular promise many proposed devices rely on these forms, namely the heaving buoy bottom hinged surging flap. It can be that to achieve resonance a point absorber requires diameter is much larger than practical. By contrast, flaps are generally smaller, hence flap non resonant. This paper proposes hybrid of two topologies, in form an off-set The exact...
This paper describes an extension of the method moments to allow full solutions a reentrant cavity for modes with azimuthal variation by coupling TE and TM at interface between two regions. In addition treatment MBK stability using wake field theory is proposed.