Download or read book Beam Halo Dynamics and Control With Hollow Electron Beams written by and published by . This book was released on 2012 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Conceptual Design of Hollow Electron Lenses for Beam Halo Control in the Large Hadron Collider written by and published by . This book was released on 2014 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. We are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. The expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were checked to ensure that undesired effects were suppressed. Hardware specifications were based on the Tevatron devices and on preliminary engineering integration studies in the LHC machine. Required resources and a possible timeline were also outlined, together with a brief discussion of alternative halo-removal schemes and of other possible uses of electron lenses to improve the performance of the LHC.

Download or read book Hollow Electron Beam Collimation for HL LHC Effect on the Beam Core written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Collimation with hollow electron beams or lenses (HEL) is currently one of the most promising concepts for active halo control in HL-LHC. In previous studies it has been shown that the halo can be efficiently removed with a hollow electron lens. Equally important as an efficient removal of the halo, is also to demonstrate that the core stays unperturbed. In this paper, we present a summary of the experiment at the LHC and simulations in view of the effect of the HEL on the beam core in case of a pulsed operation.

Download or read book Measurements of Beam Halo Diffusion and Population Density in the Tevatron and in the Large Hadron Collider written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Halo dynamics influences global accelerator performance: beam lifetimes, emittance growth, dynamic aperture, and collimation efficiency. Halo monitoring and control are also critical for the operation of high-power machines. For instance, in the high-luminosity upgrade of the LHC, the energy stored in the beam tails may reach several megajoules. Fast losses can result in superconducting magnet quenches, magnet damage, or even collimator deformation. The need arises to measure the beam halo and to remove it at controllable rates. In the Tevatron and in the LHC, halo population densities and diffusivities were measured with collimator scans by observing the time evolution of losses following small inward or outward collimator steps, under different experimental conditions: with single beams and in collision, and, in the case of the Tevatron, with a hollow electron lens acting on a subset of bunches. After the LHC resumes operations, it is planned to compare measured diffusivities with the known strength of transverse damper excitations. New proposals for nondestructive halo population density measurements are also briefly discussed.

Download or read book Applications of Electron Lenses written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron lenses are pulsed, magnetically confined electron beams whose current-density profile is shaped to obtain the desired effect on the circulating beam. Electron lenses were used in the Fermilab Tevatron collider for bunch-by-bunch compensation of long-range beam-beam tune shifts, for removal of uncaptured particles in the abort gap, for preliminary experiments on head-on beam-beam compensation, and for the demonstration of halo scraping with hollow electron beams. Electron lenses for beam-beam compensation are being commissioned in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Hollow electron beam collimation and halo control were studied as an option to complement the collimation system for the upgrades of the Large Hadron Collider (LHC) at CERN; a conceptual design was recently completed. Because of their electric charge and the absence of materials close to the proton beam, electron lenses may also provide an alternative to wires for long-range beam-beam compensation in LHC luminosity upgrade scenarios with small crossing angles. At Fermilab, we are planning to install an electron lens in the Integrable Optics Test Accelerator (IOTA, a 40-m ring for 150-MeV electrons) as one of the proof-of-principle implementations of nonlinear integrable optics to achieve large tune spreads and more stable beams without loss of dynamic aperture.

Download or read book Dynamics of Beam Halo in Mismatched Beams written by and published by . This book was released on 1996 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-power proton linacs for nuclear materials transmutation and production, and new accelerator-driven neutron spallation sources must be designed to control beam-halo formation, which leads to beam loss. The study of particle-core models is leading to a better understanding of the causes and characteristics of beam halo produced by space-charge forces in rms mismatched beams. Detailed studies of the models have resulted in predictions of the dependence of the maximum amplitude of halo particles on a mismatch parameter and on the space-charge tune-depression ratio. Scaling formulas have been derived which will provide guidance for choosing the aperture radius to contain the halo without loss.

Download or read book High Luminosity Large Hadron Collider The New Machine For Illuminating The Mysteries Of The Universe Second Edition written by Lucio Rossi and published by World Scientific. This book was released on 2024-02-06 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the physics and technology of the High-Luminosity Large Hadron Collider (LHC), highlighting the most recent modifications that shaped the final configuration, which is now in the advanced stages of its construction.This new High-Luminosity configuration of the LHC is the major accelerator project of this decade and will give new life to the LHC after its first fifteen years of operation, allowing for more precise measurements of the Higgs Boson and extending the mass limit reach for new particles.The LHC is such a highly optimized machine that upgrading it requires breakthroughs in many areas. Unsurprisingly, the High-Luminosity LHC required a long R&D period to bring into life an innovative accelerator magnet, based on Nb3Sn and capable of generating fields in the 11-12 T range, as well as many other new accelerator technologies such as superconducting compact RF crab cavities, advanced collimation concepts, a novel powering technology based on high temperature superconducting links, and others.The book is a self-consistent series of papers, which addresses all technology and design issues. Each paper can be read separately as well. The first few papers provide a summary of the whole project, the physics motivation, and the accelerator challenges. Altogether, this book brings the reader to the heart of the technologies that will also be key for the next generation of hadron colliders.This book is an essential reference for physicists and engineers in the field of hadron colliders and LHC related issues and can also be read by postgraduate students.

Download or read book Halo Formation and Hollowing in Relativistic Electron Beams written by Richard F. Hubbard and published by . This book was released on 1988 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: A relativistic electron beam propagating through dense gas may evolve to a variety of current density profiles J sub b (r) depending on the beam temperature T and plasma current profile J sup P (r). Four broad classes of equilibria are identified in particle simulations: (1) Bennett-like or compact, (2) core and halo, (3) on-axis hollowed and (4) off-axis hollowed. The qualitative features of each class are reproduced in a simple analytical model which assumes an isothermal beam and a Bennett plasma current profile and iterates about an initial ansatz of a Bennett beam current profile. Bennett-like equilibria are produced when the return current fraction f is small or when T/T sub B = 1-f, where T sub B> 1-f and moderate or high f, the equilibrium consists of a compact core surrounded by a halo which may contain most of the beam current. In extreme cases (T/T sub B” 1-f and f close to unity), an off-axis density minimum occurs. (This is also referred to as off-axis hollowing.) For T/T sub B

Download or read book Simulation of Hollow Electron Beam Collimation in the Fermilab Tevatron Collider written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The concept of augmenting the conventional collimation system of high-energy storage rings with a hollow electron beam was successfully demonstrated in experiments at the Tevatron. A reliable numerical model is required for understanding particle dynamics in the presence of a hollow beam collimator. Several models were developed to describe imperfections of the electron beam profile and alignment. The features of the imperfections are estimated from electron beam profile measurements. Numerical simulations of halo removal rates are compared with experimental data taken at the Tevatron.

Download or read book Beam Dynamics in an Electron Lens with the Warp Particle in cell Code written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron lenses are a mature technique for beam manipulation in colliders and storage rings. In an electron lens, a pulsed, magnetically confined electron beam with a given current-density profile interacts with the circulating beam to obtain the desired effect. Electron lenses were used in the Fermilab Tevatron collider for beam-beam compensation, for abort-gap clearing, and for halo scraping. They will be used in RHIC at BNL for head-on beam-beam compensation, and their application to the Large Hadron Collider for halo control is under development. At Fermilab, electron lenses will be implemented as lattice elements for nonlinear integrable optics. The design of electron lenses requires tools to calculate the kicks and wakefields experienced by the circulating beam. We use the Warp particle-in-cell code to study generation, transport, and evolution of the electron beam. For the first time, a fully 3-dimensional code is used for this purpose.

Download or read book Introduction to Beam Dynamics in High energy Electron Storage Rings written by Andrzej Wolski and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron storage rings play a crucial role in many areas of modern scientific research. Introduction to Beam Dynamics in High-Energy Electron Storage Rings describes the physics of particle behaviour in these machines. Starting with an outline of the history, uses and structure of electron storage rings, the book develops the foundations of beam dynamics, covering particle motion in the components used to guide and focus the beams, the effects of synchrotron radiation, and the impact of interactions between the particles in the beams.

Download or read book Development of Hollow Electron Beams for Proton and Ion Collimation written by and published by . This book was released on 2010 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams.

Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 998 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book INIS Atomindex written by and published by . This book was released on 1996 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1982 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book IRE Transactions on Electron Devices written by and published by . This book was released on 1959 with total page 1454 pages. Available in PDF, EPUB and Kindle. Book excerpt: