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In this paper, we describe newly developed tools for the study and analysis of the dynamics in FFAG accelerators based on transfer map methods unique to the code COSY INFINITY. With these new tools, closed orbits, transverse amplitude dependencies and dynamic aperture are determined inclusive of full nonlinear fields and kinematics to arbitrary order. The dynamics are studied at discrete energies, via a high-order energy-dependent transfer map.

The order-dependent convergence in the calculated maps allows precise determination of dynamic aperture and detailed particle dynamics. Using normal form methods, and minimal impact symplectic tracking, amplitude- and energy-dependent tune shifts and resonance strengths are extracted. Optimization by constrained global optimization methods further refine and promote robust machine attributes.

Various methods of describing the fields will be presented, including representation of fields in radius-dependent Fourier modes, which include complex magnet edge contours and superimposed fringe fields, as well as the capability to interject calculated or measured field data from a magnet design code or actual components, respectively.

The document summarizes the recent papers, presentations and other public information on Radio-Frequency (RF) Linear Accelerators (linacs) and Fixed-Field Alternating-Gradient (FFAG) accelerators for hadron therapy. The main focus is on technical aspects of these accelerators. This report intends to provide a general overview of the state-of-the-art in those accelerators which could be used in short and middle-term for treating cancer.

Progress in the study of beam optics and acceleration of the scaling FFAG accelerator has been presented in this paper.

Non-scaling FFAG (NS-FFAG) rings have been proposed as a solution for muon acceleration in the Neutrino Factory. In order to achieve small orbit excursion and small time of flight variation, lattices with a very compact cell structure and consequent short straight sections are required. The resulting geometry, combined with the large transverse emittance of the muon bunch, places very challenging constraints on the injection/extraction systems. The injection/extraction system requires a set of distributed kickers, a superconducting septum and increased aperture in some of the main ring magnets. A scheme for both injection and extraction for a FFAG with triplet geometry is presented. In addition, a solution for the required kicker magnets is proposed.

Non-scaling FFAGs have gained interest in the past decade for their potential application to charged particle therapy using proton and ion beams. However, linear ns-FFAGs naturally cross betatron resonances throughout acceleration. With an acceleration cycle of thousands rather than tens of turns, we find that resonance crossing produces severe orbit distortion in a linear proton/ion ns-FFAG in the presence of alignment errors. To overcome this, the PAMELA (Particle Accelerator for MEdicaL Applications) lattice design avoids resonance crossing with a non-linear ns-FFAG design. This design is outlined and a comparative analysis of alignment tolerances presented.

PAMELA(Particle Accelerator for Medical Application) aims to design a particle therapy facility using NS-FFAG(Non-Scaling Fixed Field Alternating Gradient) accelerator. A newly proposed lattice design and the new type of combined function magnet provide the accelerator flexible tuneability of operating point and variability in operation modes. A remarkable features for a fixed field accelerator are its high repetition rate, about 1 kHz, and energy variable beam extraction. These features make the machine a promising candidate of versatile accelerator not restricted to medical applications.

The Cornell-BNL Electron Test Accelerator (CBETA), a four-pass, 150 MeV energy recovery linac (ERL), is now in construction at Cornell. Commissioning commenced on March 2019. A particularity of CBETA is that a single channel loop recirculates the four energies (42, 78, 114 and 150 MeV). The return loop arcs are based on fixed-field alternating gradient (FFAG) optics. The loop is comprised of 107 quadrupole-doublet cells, built using Halbach permanent magnet technology. Spreader and combiner sections (4 independent beam lines each) connect the 36 MeV linac to the FFAG arcs. We introduce here a start-to-end simulation of the 4-pass ERL, based entirely, and exclusively, on the use of magnetic field maps to model the optical components.

A brief review is given of the development of linacs, cyclotrons, synchrotrons (also accumulators) and FFAG accelerators for a variety of high power hadron beam applications.

This article describes particle accelerators using magnets whose field strengths are fixed in time to steer and focus ion beams in a spiral orbit so that they pass between (and can be accelerated by) the same electrodes many times. The first example of such a device, Lawrence's cyclotron, revolutionized nuclear physics in the 1930s, but was limited in energy by relativistic effects. To overcome these limits two approaches were taken, enabling energies of many hundreds of MeV/u to be reached: either frequency-modulating the rf accelerating field (the synchrocyclotron) or introducing an azimuthal variation in the magnetic field (the isochronous or sector-focused cyclotron). Both techniques are applied in fixed-field alternating-gradient accelerators (FFAGs), which were intensively studied in the 1950s and '60s with electron models. Technological advances have made possible the recent construction of several proton FFAGs, and a wide variety of designs is being studied for diverse applications with electrons, muons, protons and heavier ions. All fixed-field accelerators offer high beam intensity: classical and isochronous cyclotrons operate in cw mode and in some cases deliver beams of 2 mA; synchrocyclotrons and most FFAGs operate in pulsed mode, but are capable of much higher pulse repetition rates (≤ kHz) than synchrotrons.

This review summarizes projects and studies on circular accelerators proposed for driving subcritical reactors. The early isochronous cyclotron cascades, proposed about 20 years ago, and the evolution of these layouts up to the most recent solutions or designs based on cyclotrons and fixed field alternating gradient accelerators, are reported. In addition, the newest ideas and their prospects for development are discussed.

A brief review is given of the development of linacs, cyclotrons, synchrotrons (also accumulators) and FFAG accelerators for a variety of high power hadron beam applications.

This article describes particle accelerators using magnets whose field strengths are fixed in time to steer and focus ion beams in a spiral orbit so that they pass between (and can be accelerated by) the same electrodes many times. The first example of such a device, Lawrence's cyclotron, revolutionized nuclear physics in the 1930s, but was limited in energy by relativistic effects. To overcome these limits two approaches were taken, enabling energies of many hundreds of MeV/u to be reached: either frequency-modulating the rf accelerating field (the synchrocyclotron) or introducing an azimuthal variation in the magnetic field (the isochronous or sector-focused cyclotron). Both techniques are applied in fixed-field alternating-gradient accelerators (FFAGs), which were intensively studied in the 1950s and '60s with electron models. Technological advances have made possible the recent construction of several proton FFAGs, and a wide variety of designs is being studied for diverse applications with electrons, muons, protons and heavier ions. All fixed-field accelerators offer high beam intensity: classical and isochronous cyclotrons operate in cw mode and in some cases deliver beams of 2 mA; synchrocyclotrons and most FFAGs operate in pulsed mode, but are capable of much higher pulse repetition rates (≤ kHz) than synchrotrons.

This review summarizes projects and studies on circular accelerators proposed for driving subcritical reactors. The early isochronous cyclotron cascades, proposed about 20 years ago, and the evolution of these layouts up to the most recent solutions or designs based on cyclotrons and fixed field alternating gradient accelerators, are reported. In addition, the newest ideas and their prospects for development are discussed.

Fixed Field Alternating Gradient accelerators(FFAGs) have been developed for various applications recently. Contrary to the ordinary synchrotron, FFAGs have a large capability of accelerating high current beams because of strong beam focusing to have a large beam acceptance and static magnetic field which allows to have very fast beam acceleration and large repetition rate in operation. In this paper I will present the expected characteristics and possible performance of FFAG as the proton drivers for ADSR and muon source, and also show the recent preliminary experiment on ADSR with FFAG proton accelerator complex at Kyoto University Research Reactor Institute (KURRI).

A review is given of present and planned involvement in ADSR research in the UK, and the activities of the ThorEA association.