A5101533607- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Gyrotron and Vacuum Electronics Research
- Particle Detector Development and Performance
- Advanced X-ray Imaging Techniques
- Magnetic confinement fusion research
- Photocathodes and Microchannel Plates
- Particle physics theoretical and experimental studies
- Muon and positron interactions and applications
- Advancements in Photolithography Techniques
- Electromagnetic Simulation and Numerical Methods
- Plasma Diagnostics and Applications
- Black Holes and Theoretical Physics
- Laser-Plasma Interactions and Diagnostics
- International Science and Diplomacy
- Optical Coatings and Gratings
- Crystallography and Radiation Phenomena
- Atomic and Molecular Physics
- Distributed and Parallel Computing Systems
- Cosmology and Gravitation Theories
- Electron and X-Ray Spectroscopy Techniques
- Advanced Data Storage Technologies
- Nuclear Physics and Applications
- Advanced Surface Polishing Techniques
SLAC National Accelerator Laboratory
2015-2024
University of Dallas
2024
The University of Tokyo
2023-2024
Menlo School
2004-2022
Brookhaven National Laboratory
2021
Thomas Jefferson National Accelerator Facility
2015-2019
Stanford University
2006-2017
Linac Coherent Light Source
2003-2017
European Organization for Nuclear Research
2002-2013
Stanford Synchrotron Radiation Lightsource
1997-2008
The machine commissioning of KEKB started in December 1998 and its operation was terminated at the end June 2010 to upgrade SuperKEKB. In this paper, we summarize history show achievements made there.
The International Linear Collider (ILC) is on the table now as a new global energy-frontier accelerator laboratory taking data in 2030s. ILC addresses key questions for our current understanding of particle physics. It based proven technology. Its experiments will challenge Standard Model physics and provide window to look beyond it. This document brings story up date, emphasizing its strong motivation, readiness construction, opportunity it presents US community.
Energy extraction efficiency of a free electron laser (FEL) can be greatly increased using tapered undulator and self-seeding. However, the rate is limited by various effects that eventually lead to saturation peak intensity power. To better understand these effects, we develop model extending Kroll-Morton-Rosenbluth, one-dimensional theory include physics diffraction, optical guiding, radially resolved particle trapping. The predictions agree well with GENESIS single-frequency numerical...
We have designed an ``ultimate'' storage ring for a future light source that would be resided in the positron-electron-project (PEP) tunnel and achieves diffraction-limited emittances (at 1.5 \AA{}) of 12 pm-rad both horizontal vertical planes with 4.5-GeV electron beam. These include contribution intrabeam scattering at nominal current 200 mA 3300 bunches. This quality beam conjunction conventional 4-m undulator straight section can generate synchrotron radiation having spectral brightness...
We use a Vlasov-Fokker-Planck program and linearized Vlasov solver to study the microwave instability threshold of impedance models: (1) $Q=1$ resonator (2) shielded coherent synchrotron radiation (CSR), find results two programs agree well. For CSR we show that only dimensionless parameters, shielding parameter $\ensuremath{\Pi}$ strength ${S}_{\mathrm{csr}}$, are needed describe system. further there is strong associated with CSR, threshold, good approximation, given by...
A preliminary lattice design of a muon collider ring with the center-of-mass (CM) energy 6 TeV is presented. The circumference 6.3 km, and beta function at collision point β* = 1 cm in each plane. linear optics, local non-linear chromaticity compensation Interaction Region (IR), additional IR correction knobs, effects fringe field are discussed. Magnet specifications based on maximum pole-tip 20 T dipoles 15 quadrupoles. Careful chromatic amplitude dependent provides sufficiently large...
An object-oriented accelerator design code has been designed and implemented in a simple modular fashion. It contains all major features of its predecessors: TRACY DESPOT. All physics single-particle dynamics is based on the Hamiltonian local frame component. Components can be moved arbitrarily three dimensional space. Several symplectic integrators are used to approximate integration Hamiltonian. A differential algebra class introduced extract Taylor map up arbitrary order. Analysis optics...
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 well-known Haissinski distribution provides a stable equilibrium of longitudinal beam in electron storage rings below threshold current. Yet, how to accurately determine this threshold, above which the becomes unstable, is not firmly established theory. In paper, we will show apply Laguerre polynomials an analysis stability that are associated with potential-well distortion. Our approach alternative discretization method proposed by Oide and Yokoya. Moreover, it reestablishes essential...
Abstract The LHC@Home BOINC project has provided computing capacity for numerical simulations to researchers at CERN since 2004, and 2011 been expanded with a wider range of applications. traditional accelerator physics simulation code SixTrack enjoys continuing volunteers support, thanks virtualisation number applications from the LHC experiment collaborations particle theory groups have joined consolidated project. This paper addresses challenges related virtualized in environment, how...
In recent high luminosity colliders, the finite crossing angle scheme becomes popular to gain with multibunch or long bunch operation. Success of KEKB factory showed that has no problem achieving beam-beam parameters up 0.05. We have studied interactions and without toward higher luminosity. discuss how affects parameter in present using computer simulations. The simulations crab cavities, which realize head-on collision effectively, can be expected double
In the continuing efforts to reduce beam emittance of an electron storage ring composed theoretical minimum (TME) lattice, down a level several tens picometers, nonlinear dynamics grows be great challenge performance because strong sextupoles needed compensate for its large global natural chomaticities coupled with small average dispersion function. To help in dealing optimization, we propose novel variation named as ``modified-TME'' minimal about 3 times exact minimum, while more compact...
We study coherent synchrotron radiation by electrons in the Frenet-Serret coordinate system with a constant curvature $1/\ensuremath{\rho}$. Based on Hamiltonian Courant-Synder theory of particle accelerators, we find general that transverse force is essentially Lorentz but substitution magnetic field ${B}_{x,y}\ensuremath{\rightarrow}(1+x/\ensuremath{\rho}){B}_{x,y}$, where $x$ and $y$ are positions. The term provides us key to derive point-charge wakefield explicitly terms incomplete...
A highly accurate self-consistent particle code to simulate the beam-beam collision in ${e}^{+}{e}^{\ensuremath{-}}$ storage rings has been developed. It adopts a method of solving Poisson equation with an open boundary. The consists two steps: assigning potential on finite boundary using Green's function and then inside fast solver. Since solution Poisson's is unique, our exactly same as one obtained by simply function. allows us select much smaller region mesh therefore increase resolution...
The ion-caused beam instability in the future light sources and electron damping rings can be serious due to high current ultrasmall emittance of picometer level. One simple effective mitigation is a multibunch train filling pattern which significantly reduce ion density near beam, therefore growth rate up 2 orders magnitude. suppression more for intensity beams with low emittance. distribution electric field trapped ions are benchmarked validate model used paper. wakefield cloud beam-ion...
There is a worldwide interest in developing so-called ultimate storage ring (USR) light sources having electron emittances near the X-ray diffraction limit that would provide spectral brightness one or two orders of magnitude higher than present-day, third-generation and very large coherent flux multi-keV photon energy range [1 Hettel, R. Qin, Q. 2013. Report on Workshop Accelerator R&D for Ultimate Storage Rings, Oct. 30–Nov. 1, 2012, Beijing, China, SLAC-PUB-15379, February [Google...
A weak vertical coupled-bunch instability with oscillation amplitude of the order a few $\ensuremath{\mu}\mathrm{m}$ has been observed in SPEAR3 at nominal vacuum pressure. The becomes stronger increasing neutral gas pressure as by turning off pumps, and weaker when beam emittance is increased. These observations indicate that motion driven ions trapped periodic potential electron beam. In this paper we present series comprehensive measurements, impedance-based stability analysis, numerical...