A5076712155- Particle accelerators and beam dynamics
- Particle Accelerators and Free-Electron Lasers
- Gyrotron and Vacuum Electronics Research
- Superconducting Materials and Applications
- Microwave Engineering and Waveguides
- Particle Detector Development and Performance
- Pulsed Power Technology Applications
- Electromagnetic Simulation and Numerical Methods
- Radio Frequency Integrated Circuit Design
- Photonic and Optical Devices
- Advanced Frequency and Time Standards
- Particle physics theoretical and experimental studies
- Magnetic confinement fusion research
- Superconducting and THz Device Technology
- Plasma Diagnostics and Applications
- Advanced X-ray Imaging Techniques
- Advanced Surface Polishing Techniques
- Superconductivity in MgB2 and Alloys
- Electrostatic Discharge in Electronics
- Dark Matter and Cosmic Phenomena
- Physics of Superconductivity and Magnetism
- Electronic Packaging and Soldering Technologies
- Wireless Power Transfer Systems
- Laser-Plasma Interactions and Diagnostics
- Soil Moisture and Remote Sensing
European Organization for Nuclear Research
2015-2024
University of Strathclyde
2021
Lancaster University
2017-2020
Instituto de Física Corpuscular
2020
Tsinghua University
2019
Moscow University of Finance and Law
2017
A possible design of a multi-TeV e+e- linear collider is presented. The based on the CLIC (Compact Linear Collider) two-beam technology proposed and developed at CERN. Though study has shown that this applicable to with centre-of-mass energies from 500 GeV or less up 5 TeV, present report focuses nominal energy 3 Te V. First, short overview given physics could possibly be done such collider. Then, description main-beam complex covers injection system, 30 GHz main linac, beam delivery system....
The increase in efficiency of RF power generation for future large accelerators is considered a high priority issue. vast majority the existing commercial high-power klystrons operates electronic range between 40% and 55%. Only few available on market are capable operating with 65% or above. In this paper, new method to achieve 90% conversion klystron amplifier presented. essential part bunching technique - bunch core oscillations. Computer simulations confirm that production above can be...
The High Efficiency International Klystron Activity (HEIKA) was initiated at CERN in 2014 to evaluate and develop new klystron bunching technologies for high-efficiency klystrons application the large-scale scientific projects such as Compact Linear Collider (CLIC) Future Circular (FCC). success of development strongly depends on availability specialized computer codes. Unfortunately, accurate efficient 2-D large-signal codes are proprietary not freely available wide community. 1.5-D code...
Compactness and cost-effectiveness are two major concerns in the development of a Ka-band linearizer, which is crucial accelerator component European CompactLight project. A higher order mode (HOM) multibeam Klystron (MBK) could accommodate distributed electron current with low operating voltage 60 kV, thus making it competitive to deliver high RF power at frequency compared single beam or fundamental MBK. In this article, modeling design study 36-GHz HOM MBK presented. The double...
The RF power production efficiency is one of the major concerns in 3-TeV Compact Linear Collider (CLIC) Drive Beam Accelerator, as it responsible for almost 50% entire accelerator complex consumption. klystron technology with dc post acceleration prebunched beam was reconsidered recently, an attempt to develop a technological solution high efficiency, L -band multibeam klystrons (MBKs). In this article, modeling and design study CLIC MBK two-stage (TS) configuration presented. TS performance...
One priority of the CLIC (Compact Linear Collider) accelerating-structure development program has been to investigate ways achieve accelerating gradients above 150 MV/m. Two main concepts such high have emerged: reduced surface field geometries and use alternative materials. An experimental demonstration these two made in CTFII (CLIC Test Facility) using three 30 GHz structures: one entirely from copper, with copper cavity walls tungsten irises molybdenum irises. A peak gradient over 190...
We present an X-band high-power pulse compression system for a klystron-based compact linear collider. In this design, one rf power unit comprises two klystrons, correction cavity chain, and SLAC Energy Doubler (SLED)-type compressors (SLEDX). An passes the by which shape is modified. The then equally split into ways, each deploying SLEDX to compress power. Each produces short with length of 244 ns peak 217 MW four accelerating structures. With help phase-to-amplitude modulation, has...
CERN has constructed and is operating a klystron- based X-band test stand, called Xbox-1, dedicated to the high-gradient testing of prototype accelerating structures for CLIC other applications such as FELs. The stand now been in operation year significant progress made understanding system, improving its reliability, upgrading hardware implementing automatic algorithms conditioning structures.
The CLIC study has progressively tested prototype accelerating structures which incorporate an ever increasing number of features are needed for a final version ready to be installed in linear collider. most recent high power test made the CERN X-band stand, Xbox-1, is CERN-built includes damping but also compact input and output couplers, maximize overall length active gradient ratio structure. structure’s high-gradient performance, 105 MV/m at 250 ns pulse low breakdown rate, matches...
A semianalytical parametric scaling procedure (PSP) for klystron design has been developed. The PSP allows existing designs to be scaled different operating frequencies, beam power, and perveance, while maintaining the electron bunching deceleration processes. For fixed layout of a RF circuit, provides parameters which are nearly optimal. theoretical background step by derivation principles presented. effectiveness is shown through generic five-cavity L-band klystron.
Klystrons employing traditional monotonic electron bunching are capable of efficiencies up to ~70%. The use the core oscillation method (COM) has predicted a significant improvement in efficiency towards 90%. Here, we document refinements on previously presented geometries, with PIC simulations predicting 85%.
One of the major objectives CTF3 (CLIC Test Facility) is production 30 GHz power for high-gradient testing CLIC accelerating structures. To this end a dedicated beam line, generating structure and transfer line have been designed, installed commissioned. 52 MW with pulse length 74 ns repetition rate 16 Hz were delivered to test area. This will allow operation structures in first run 2005 up nominal gradient 150 MV/m beyond length. The system described performances linac, rf components are reviewed.
A novel high-gradient accelerating structure with low phase velocity, $v/c=0.38$, has been designed, manufactured and high-power tested. The was designed built using the methodology technology developed for CLIC $100\text{ }\text{ }\mathrm{MV}/\mathrm{m}$ structures, which have speed of light but adapts them to a nonrelativistic particles. parameters were optimized compact proton therapy linac project, specifically 76 MeV energy protons, type opens more generally possibility velocity linacs....
The CLIC study is high power testing accelerating structures in a number of different materials and structure designs to understand the physics breakdown, determine appropriate scaling performance particular find ways increase achievable gradient. most recent 30 GHz which have been tested include damped copper, molybdenum, titanium aluminum. results from these new are presented this paper.
The CLIC power extraction and transfer structure (PETS) is a passive microwave device in which bunches of the drive beam interact with impedance periodically loaded waveguide excite preferentially synchronous mode. RF produced (several hundred MW) collected at downstream end by means Power Extractor delivered to main linac structure. PETS geometry result multiple compromises between stability needs. Another requirement provide local termination case accelerating failure (ON/OFF capability)....
This paper outlines the results obtained from Magic software for CSM_23 (Core Stabilization Method) klystron. klystron implements use of a second and third harmonic to increase efficiency. From PIC simulation an efficiency 78.1% was achieved.
New developments relating to compact X-band, SLED-I type pulse compressors being developed at CERN for testing high gradient structures are described. Pulse of interest take rf pulses from one or more power klystrons with duration typically $>1.5\text{ }\text{ }\ensuremath{\mu}\mathrm{s}$ and deliver up 5 times the input a shorter $<250\text{ }\mathrm{ns}$. Time domain models compressor operation low level (LLRF) control have been developed. Input drive amplitude phase each is evolved...
High-frequency, high-power klystrons proved to be significant for application in compact particle accelerators, high-resolution radars, and fast data communication systems. As most of the linear beam devices, performance klystron deteriorates progressively with an increasing operating frequency due reduction individual RF cavity impedances. Coupled cell structures can alleviate such degradation by extending beam-wave interaction region. The accurate simulation coupled structure relies on...
We discuss $X$-band rf power production and deceleration in the two-beam test stand of CLIC facility at CERN. The is extracted from an electron drive beam by a specially designed extraction structure. In order to structures high-power levels, part generated recirculated input port, thus allowing for increased levels within degree recirculation controlled splitter phase shifter. present model that describes system validate it with measurements over wide range parameters. Moreover, correlating...
A compact X-band correction cavity chain (CC) has been successfully designed, fabricated and high power tested for the Compact Linear Collider (CLIC) project. The CC consists of eight spherical cavities four polarizers, each a ${Q}_{0}$ 45 000 diameter 7 cm. can correct decaying pulse shape generated by storage without need low efficiency modulation or solution based on long delay lines. flattop output with small ripples be obtained if are matched. Experiments barrel open (BOC) were...