A5075400886- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Particle Detector Development and Performance
- Gyrotron and Vacuum Electronics Research
- Particle physics theoretical and experimental studies
- Magnetic confinement fusion research
- Plasma Diagnostics and Applications
- Distributed and Parallel Computing Systems
- Advanced Data Storage Technologies
- Electron and X-Ray Spectroscopy Techniques
- Semantic Web and Ontologies
- Advanced Database Systems and Queries
- Electromagnetic Simulation and Numerical Methods
- High-Energy Particle Collisions Research
- Microwave Engineering and Waveguides
- Service-Oriented Architecture and Web Services
- Atomic and Molecular Physics
- Electrostatic Discharge in Electronics
- Fusion materials and technologies
- Scientific Computing and Data Management
- Advancements in Semiconductor Devices and Circuit Design
- Laser-Plasma Interactions and Diagnostics
- Pulsed Power Technology Applications
- Semiconductor materials and devices
European Organization for Nuclear Research
2014-2024
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2007-2018
Technical University of Darmstadt
2018
Istituto Nazionale di Fisica Nucleare
2007
High Energy Accelerator Research Organization
2006
GSI Helmholtz Centre for Heavy Ion Research
1998-2006
Brookhaven National Laboratory
2004
Universitat de València
2004
RIKEN BNL Research Center
2004
Istituto Nazionale di Fisica Nucleare, Sezione di Napoli
1999-2000
Present and future accelerators' performances may be limited by the electron cloud (EC) effect. The EC formation evolution are determined wall-surface properties of accelerator vacuum chamber. We present measurements total secondary yield (SEY) related energy distribution curves electrons as a function incident-electron energy. Particular attention has been paid to emission process due very low-energy primary ($<20\text{ }\text{ }\mathrm{e}\mathrm{V}$). It is shown that SEY approaches unity...
Electron cloud buildup is a major limitation for high-energy particle accelerators such as the CERN Super Proton Synchrotron (SPS). Amorphous carbon thin films with low initial secondary electron yield ($\mathrm{SEY}\ensuremath{\cong}1.0$) have been applied mitigation material in SPS vacuum chambers. This paper summarizes experimental setups monitoring, coating procedures, and recent measurements performed amorphous coated chambers SPS. The measured by dedicated monitors completely...
Beam instabilities cover a wide range of effects in particle accelerators and they have been the subjects intense research for several decades. As machines performance was pushed new mechanisms were revealed nowadays challenge consists studying interplays between all these intricate phenomena, as it is very often not possible to treat different separately. The aim this paper review main mechanisms, discussing particular recent developments beam instability theories simulations.
Photoemission and secondary emission are known to give rise a quasistationary electron cloud inside the beam pipe through beam-induced multipacting process. We investigate electron-cloud build up related effects via computer simulation. In our model, macroparticles representing photoelectrons emitted synchronously with passing proton or positron bunch subsequently accelerated in field of beam. As they hit pipe, new macroelectrons generated, whose charges determined by energy incoming...
Physics Beyond Colliders is an exploratory study aimed at exploiting the full scientific potential of CERN's accelerator complex and its infrastructure in next two decades through projects complementary to LHC, HL-LHC other possible future colliders. These should target fundamental physics questions that are similar spirit those addressed by high-energy colliders, but require different types beams experiments. A kick-off workshop held September 2016 identified a number areas interest working...
HEADTAIL is a simulation program developed at CERN which aimed studying the single-bunch instability arising from interaction on successive turns of single bunch with cloud generated by previous bunches. The code includes chromaticity, space charge tune spread, broad-band impedance, and detuning amplitude for more realistic simulation. Examples application are shown. Transverse longitudinal wake functions also outputs code.
Recently, resonance driving terms were successfully measured in the CERN SPS and BNL RHIC from Fourier spectrum of beam position monitor (BPM) data. Based on these measurements a new analysis has been derived to extract truly local observables BPM These are called since they share some similarities with global terms. In this paper we derive analytically present experimental sextupolar RHIC. Nondestructive using ac dipoles also presented.
During the beam commissioning of Large Hadron Collider (LHC) [LHC Design Report No. CERN-2004-003-V-1, 2004 [http://cds.cern.ch/record/782076?ln=en]; O. Br\"uning, H. Burkhardt, and S. Myers, Prog. Part. Nucl. Phys. 67, 705 (2012)] with 150, 75, 50, 25-ns bunch spacing, important electron-cloud effects, like pressure rise, cryogenic heat load, instabilities, or emittance growth, were observed. Methods have been developed to infer different key beam-pipe surface parameters by benchmarking...
The interaction between a low-density electron cloud in circular particle accelerator with circulating charged beam is considered. beam's space charge attracts the cloud, enhancing density near axis. It shown that this enhanced and image charges associated conducting wall of may have important consequences for dynamics propagation. tune shift due to obtained analytically compared new numerical model (QuickPIC) described here. Sample results are presented their significance current planned...
The Future Circular Collider FCC-ee is a study toward high luminosity electron-positron collider with centre-of-mass energy from 91 GeV to 365 GeV. Due the beam parameters and pipe dimensions, collective effects electron cloud can be very critical aspects for machine represent main limitations its performance. An estimation of build up in components an impedance model are required analyze induced instabilities find solutions their mitigation. Special attention has been given resistive wall...
The Large Hadron Collider (LHC) is one of the largest scientific instruments ever built. Since opening up a new energy frontier for exploration in 2010, it has gathered global user community working fundamental particle physics and hadronic matter at extreme temperature density. To sustain extend its discovery potential, LHC will undergo major upgrade 2020s. This increase rate collisions by factor five beyond original design value integrated luminosity ten. configuration, known as High...
The Experimental Cavern North 3 (ECN3) is an underground experimental cavern on the CERN Pr\'evessin site. ECN3 currently hosts NA62 experiment, with a physics programme devoted to rare kaon decays and searches of hidden particles approved until Long Shutdown (LS3). Several options are proposed longer term in order make best use worldwide unique potential high-intensity/high-energy proton beam extracted from Super Proton Synchrotron (SPS) ECN3. current status their study by Physics Beyond...
The longitudinal space charge and resistive wall impedances have been investigated in a smooth cylindrical beam pipe. At any point from the axis, we obtained an expression for total impedance, which at surface r=a infinite pipe conductivity gives impedance that was derived by Zotter Kheifets studying of uniform beams concentric chambers, when single chamber is considered [B. W. S. A. Kheifets, Impedances Wakes High-Energy Particle Accelerators (World Scientific, Singapore, 1998), Chap. 6]. A...
The aim of our study is the numerical computation wakefield and energy loss per unit length for relativistic, short ($<10\text{ }\text{ }\mathrm{ns}$) proton bunches interacting with an electron cloud inside beam pipe. We present analytical expressions in impulse kick approximation. For simulation wakefields a 2D self-consistent, electrostatic particle-in-cell (PIC) code employed. Results are presented parameter scope CERN LHC SPS. selected parameters results compared to three-dimensional...
To achieve high luminosity at the collision point of Compact Linear Collider (CLIC), normalized horizontal and vertical emittances electron positron beams must be reduced to 500 4 nm before enter 1.5 TeV linear accelerators. An effective way accomplish ultralow with only small effects on polarization is using damping rings operating 2.86 GeV equipped superconducting wiggler magnets. This paper describes a technical design concept for CLIC wigglers.
CERN is currently carrying out an ambitious improvement programme of the full LHC Injectors chain in order to enable delivery beams with challenging HL-LHC parameters. The Upgrade project coordinates this massive upgrade program, and covers a new linac (Linac4 project) as well upgrades Proton Synchrotron Booster, Super Synchrotron. heavy ion injector also included, adding Linac3 Low Energy Ion Ring list accelerators concerned. performance objectives roadmap main will be presented, including...
The electron cloud may cause transverse single-bunch instabilities of proton beams such as those in the Large Hadron Collider (LHC) and CERN Super Proton Synchrotron (SPS). We simulate these consequent emittance growth with code HEADTAIL, which models turn-by-turn interaction between beam. Recently some new features were added to code, particular, electric conducting boundary conditions at chamber wall, feedback, variable beta functions. sensitivity several numerical parameters has been...
The transverse impedance in the LHC is expected to be dominated by numerous collimators, most of which are made Fibre-Reinforced-Carbon withstand impacts high intensity proton beams case failures, and will moved very close beam, with full gaps few millimetres, order protect surrounding super-conducting equipments. We present an estimate resistive-wall total at injection top energy, induced coupled-bunch growth rates tune shifts, finally result comparison theoretical predictions measurements...
Due to its effective pumping ability, nonevaporable getter (NEG) coating is considered for the vacuum chambers of Compact Linear Collider (CLIC) electron damping rings (EDR). The aim suppress fast beam ion instabilities. electromagnetic (EM) characterization NEG properties up ultra-high frequencies required correct impedance modeling ring (DR) components. are determined using rectangular waveguides which coated with NEG. method based on a combination complex transmission coefficient...
The beam-induced electron cloud buildup is one of the major concerns for SPS and design future LHC. During 2000 run, this effect has also been observed in PS with nominal LHC-type beam. induces a baseline distortion electrostatic pickup signals, both during last turns PS, when full bunch length reduced to less than 4 ns, transfer line between rings. In year 2001, modifications rf hardware allowed us study properties beam instability related phenomenon total about 10 ns. complete set...