We report on the first observation of the fast beam–ion instability (FBII), at the Advanced Light Source (ALS). The FBII [1, 2] is a novel single-pass instability, which is similar to the classical beam break up instability in a linac. Unlike the classical trapped-ion instability, the FBII cannot be cured by a clearing gap in the bunch train, and it is predicted to be a potential limitation for...

In this paper we demonstrate that cyclotrons can be made to have precisely constant betatron tunes over wide energy ranges. particular, show the horizontal tune and does not follow Lorentz factor gamma, while still perfectly satisfying isochronous condition. To make demonstration developed a technique based on calculation of entirely from geometry realistic non-hard-edge closed orbits. We prese...

The University of Maryland Electron Ring (UMER), currently under construction, has been designed to study the physics of space-charge dominated beams at extremely large values of the betatron tune shift which exceed those of existing strong-focusing synchrotrons and rings by more than an order of magnitude. In this paper, the unique design features of this research facility, the new beam physic...

Scaling laws for the dynamic aperture due to chromatic sextupoles are investigated. The problem is addressed in a simpliied lattice model containing 4N identical cells and one linear betatron phase shifter to break the overall cell-lattice symmetry. Two families of chromatic sextupoles are used to compensate the natural chromaticity. Analytical formulae for the dynamic aperture as a function of...

We demonstrate that a beam of x-ray radiation can be generated by simply focusing a single high-intensity laser pulse into a gas jet. A millimeter-scale laser-produced plasma creates, accelerates, and wiggles an ultrashort and relativistic electron bunch. As they propagate in the ion channel produced in the wake of the laser pulse, the accelerated electrons undergo betatron oscillations, genera...

The beam optics of the PS-SPS transfer line at CERN has been studied and optimised for a variety of beams. Betatron and dispersion matching has been performed for the fixedtarget proton and ion beams, as well as for the future LHC proton beam. The techniques applied to the measurement of the optical parameters in the transfer line are discussed and experimental results are presented.

EuPRAXIA is a leading European project aimed at the development of dedicated, ground-breaking, ultra-compact accelerator research infrastructure based on novel plasma acceleration concepts and laser technology their users’ communities. Within this framework, Laboratori Nazionali di Frascati (LNF, INFN) will be equipped with unique combination an X-band RF LINAC generating high-brightness GeV-ra...

Recent polarized proton beam experiments in the IUCF Cooler Ring found an evidence for a second-order snake depolarizing resonance, when the vertical betatron tune was inadvertently set near a quarter-integer. We have also studied the possibility of spin-flipping the beam polarization in the presence of a full Siberian snake using an rf solenoid. By varying the rf solenoid’s ramp time and frequ...