Exact Matched-Beam Envelopes for Undepressed Transport in a Quadrupole Lattice with Unequal Drift Lengths and Arbitrary Field Strength.

Anderson, O. A. ; LoDestro, L. L.

Technical Information Center Oak Ridge Tennessee

关键词: Particle accelerators;    Quadrupole lattices;    Drift;    Field strength;   

RP-ID  :  DE2009953778

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

In their classic paper, Courant and Snyder studied the envelope dynamics of a circular machine with negligible space charge, piecewise constant focusing, and no drift spaces (focusing gaps); they used an expansion in focusing strength to obtain an approximate solution for the envelope. The same case, but for a straight machine, was recently analyzed and an exact solution was obtained. In the present paper we extend that recent analysis to include focusing gaps, still assuming negligible space charge. Of course, particular cases with gaps have long been studied via computer simulations; an especially complete study (including space charge) was published by Lund and Bukh. As with the simulations of Ref. (4), our analysis is not restricted to FODO; the general case of unequal drift lengths is analyzed. The motivations for finding the exact solution are: (1) ease of performing parametric studies such as those in Secs. VI and VIII; (2) to facilitate study of envelope functions in the higher bands, where approximation methods fail and simulations become difficult. In particular, we are interested in the effect of drift spaces and asymmmetry on the remarkable second-band beam compression effect previously reported for the FD case.