What prevents us from building super-high intensity accelerators? The answer is case-specific, but it often points to one of the following phenomena: machine resonances, various tune shifts (and spreads), and instabilities. These three phenomena are
interdependent in all present machines. In this paper we propose a path toward alleviating these phenomena by making accelerators nonlinear. This idea is not new: Orlov (1963) and McMillan (1967) have proposed initial ideas on nonlinear focusing systems for accelerators. However, practical implementations of such ideas proved elusive, until recently.
Integrable nonlinear motion in accelerators has the potential to introduce a large betatron tune spread to suppress instabilities and to mitigate the effects of space charge and magnetic field errors. To create such an accelerator lattice one has to
find magnetic and/or electric field combinations leading to a stable integrable motion. This paper presents families of lattices with one invariant where bounded motion can be easily created in large volumes of the phase space. In addition, it presents two examples of integrable nonlinear accelerator lattices, realizable with longitudinal-coordinate-dependent magnetic or electric fields with the stable nonlinear motion, which can be solved in terms of separable variables.
Exitation of atomic levels due to interaction with electromagnetic waves has been the subject of numerous works, both experimental and theoretical. This topic became of interest in accelerator physics in relation to high efficiency charge exchange in
jection into rings for high beam power applications. Taking equations of resonant atom-wave interaction equations as a basis, this paper shows that there exist some interesting phenomena which lead to the existence of trapped electomagnetic waves (photon traps) in a medium that consists of atoms with transition frequencies in proximity to the wave frequency. These traps may exist in random and periodic lattices, and may have very low loss rate. The atomic medium can serve as an excellent wavegiude or tool to form and transmit electromagnetic waves for applications to accelerators and to electromagnetic devices in general, where high pressure gas use is acceptable. In addition, such traps in gases may accumulate substantial energy for a long period of time, leading to the possibility of creating objects similar (or equivalent) to ball lightning.
