Related papers: Interaction Between Beams and Vacuum System Walls
Electron cloud effects have become one of the main performance limitations for circular particle accelerators operating with positively-charged beams. Among other machines worldwide, the CERN Super Proton Synchrotron (SPS), as well as the…
The effects of electron clouds on positively-charged beams have been an active area of research in recent years at particle accelerators around the world. Transverse beam-size blow-up due to electron clouds has been observed in some…
A general derivation of the beam coupling impedances produced by small discontinuities on the wall of the vacuum chamber of an accelerator is reviewed. A collection of analytical formulas for the impedances of small obstacles is presented.
In a virtual cathode oscillator, the scattering of a high-current relativistic electron beam by the anode mesh leads to formation of an electron cloud near the anode. The cloud particles possess low energy and large spread in velocities…
FCC-ee, the lepton version of the Future Circular Collider (FCC), is a 100 Km future machine under study to be built at CERN. It acquires two experiments with a highest beam energy of 182.5 GeV. FCC-ee aims to operate at four different…
Intrabeam scattering refers to the effects of the Coulomb interaction acting between pairs of charged particles within a bunch in an accelerator. One of the main consequences of intrabeam scattering is a change in the emittances of a bunch:…
When a charged particle travels across the vacuum chamber of an accelerator, it induces electromagnetic fields, which are left mainly behind the generating particle. These electromagnetic fields act back on the beam and influence its…
The electron cloud in vacuum pipes of accelerators of positively charged particle beams causes a beam energy loss which could be estimated from the synchronous phase. Measurements done with beams of 75 ns, 50 ns, and 25 ns bunch spacing in…
The collimation system is an essential part of the design of any high-power accelerator. Its functions include protection of components from accidental and intentional energy deposition, reduction of backgrounds, and beam diagnostics.…
A drastic cumulation of current density caused by electrostatic repulsion in relativistic vacuum diodes with ring-type cathodes is described theoretically and confirmed experimentally. The distinctive feature of the suggested cumulation…
Space charge forces, which arise directly from the beam's charge distribution and include the influence of image charges and currents induced by interactions with a perfectly conducting, smooth pipe, are very important in high-intensity,…
Electron beams in two-dimensional systems can provide a useful tool to study energy-momentum relaxation of electrons and to generate microwave radiation stemming from plasma-beam instabilities. Naturally, these two applications cannot…
Th is paper is motivated by the growing importance of better understanding of the phenomena and consequences of high- intensity energetic particle beam interactions with accelerator, generic target , and detector components. It reviews the…
The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated analytically at frequencies for which the wavelength is large compared to a typical size of the obstacle. Simple formulas…
Collective effects in particle accelerators are one of the key constituents for determining the ultimate particle accelerator performance. Their role is becoming increasingly important as particle accelerators are being pushed ever closer…
Beam-beam effects in eRHIC, the proposed ERL-based Electron-Ion Collider (EIC) at BNL, have several unique features distinguishing them from those in hadron-colliders and lepton-colliders. Taking the advantage of the fact that the electron…
The Future Circular Collider (FCC) study aims at designing different options of a post-LHC collider. The high luminosity electron-positron collider FCC-ee based on the crab waist concept is considered as an intermediate step on the way…
This lecture introduces major physics and technology aspects of accelerator vacuum systems. Following an introduction, in the second section generic vacuum quantities such as pressure, gas density, the gas equation, pumping speed,…
The differences of the ejection-image structures in the chromospheric lines and the coronal continuum are considered. The outer, more diffusive scattering envelope of the ejection seems to be produced by the excessive free electrons due to…
Modern electron linear accelerators are often designed to produce smooth bunch distributions characterized by their macroscopic ensemble-average moments. However, an increasing number of accelerator applications call for finer control over…