Status and challenges in beam crystallization

ビーム結晶化の現状と挑戦

Wei, J.*; Yu, P.*; 岡本 宏巳*; 百合 庸介; Li, X.-P.*; Sessler, A. M.*

Wei, J.*; Yu, P.*; Okamoto, Hiromi*; Yuri, Yosuke; Li, X.-P.*; Sessler, A. M.*

During the past several decades, beam crystallization has been studied both theoretically and experimentally. Theoretical investigations have been numerical, mainly using computer modeling based on the method of molecular dynamics, and analytical, based on phonon theory. Experimental investigations involve both ion storage rings and ion traps using both electron and laser beam cooling. Topics of interests include crystal stability in various accelerator lattices and under different beam conditions, crystalline beam formation in shear-free ring lattices with both magnets and electrodes, experimental simulation of alternating-gradient conditions with an ion trap, etc. In this paper, we first review theoretical approaches and major conclusions pertaining to beam crystallization. Then, we analyze conditions and methods of the various major experiments. Finally, we discuss, both theoretically and experimentally, some improvements, open questions, and challenges in beam crystallization.