2011 Particle Accelerator Conference - List of Authors (Zolkin, T.V.)

Paper	Title	Page
MOP062	Usage of Li-rods for Ionization Cooling of Muons	226
	A.N. Skrinsky BINP SB RAS, Novosibirsk, Russia T.V. Zolkin University of Chicago, Chicago, Illinois, USA
	Four different schemes of final ionization cooling are discussed. The first scheme is the straight channel based on lithium rods, which can provide only 4D cooling, but which can be modified to obtain 6D cooling. The helical orbit scheme with decrement redistribution is one such modification. Two other modifications use emittance redistribution and emittance exchange procedures, respectively, to transfer phase-space volume from longitudinal to transverse degrees of freedom (where the transverse degrees of freedom alternate for each successive exchange or redistribution). By emittance redistribution is meant a arbitrary redistribution of phase-space volume from one degree of freedom to another and by emittance exchange is meant a symplectic operation of emittance swap. Estimates of the final emittance, calculations of the technical parameters and simulations of beam movement are presented for each scheme. The study focused on the scheme with emittance exchange because it looks the most promising and simple, both conceptually and in terms of implementation, and it can also extend the cooling process to handle a larger initial emittance relative to the basic straight channel scheme.

WEP087	Numerical Studies of Non-Linear Dynamics in BEP	1636
	I. Koop, E. Perevedentsev BINP SB RAS, Novosibirsk, Russia T.V. Zolkin University of Chicago, Chicago, Illinois, USA
	An analysis of the dependence of experimental captured positron current data from the booster storage ring BEP (VEPP-2000 facility, BINP, Russia) on the working point position on the frequency map has uncovered a great number of different non-linear resonances. The number of captured positrons after a single injection is observed to be much less than the expected value. It is anticipated that the high degree of symmetry in the magnet system of BEP, however, should lead to the suppression of such resonances. To study this discrepancy, numerical simulations of positron beam movement under different perturbations to account for potential errors in magnetic field gradient of non-linear elements and errors in their angular location are used. The findings of this research provide qualitative explanations of the experimental work diagram and answers to two main questions, specifically “Why in the absence of skew-sextupoles in structure and small coupling are strong skew-sextupole resonances observed” and “Why skew-sextupole resonances are stronger than sextupole ones of the same harmonic”. A comparison between simulation results and analytical estimates is also presented.

Paper

Title

Page

Usage of Li-rods for Ionization Cooling of Muons

226

A.N. Skrinsky
BINP SB RAS, Novosibirsk, Russia
T.V. Zolkin
University of Chicago, Chicago, Illinois, USA

Four different schemes of final ionization cooling are discussed. The first scheme is the straight channel based on lithium rods, which can provide only 4D cooling, but which can be modified to obtain 6D cooling. The helical orbit scheme with decrement redistribution is one such modification. Two other modifications use emittance redistribution and emittance exchange procedures, respectively, to transfer phase-space volume from longitudinal to transverse degrees of freedom (where the transverse degrees of freedom alternate for each successive exchange or redistribution). By emittance redistribution is meant a arbitrary redistribution of phase-space volume from one degree of freedom to another and by emittance exchange is meant a symplectic operation of emittance swap. Estimates of the final emittance, calculations of the technical parameters and simulations of beam movement are presented for each scheme. The study focused on the scheme with emittance exchange because it looks the most promising and simple, both conceptually and in terms of implementation, and it can also extend the cooling process to handle a larger initial emittance relative to the basic straight channel scheme.

WEP087

Numerical Studies of Non-Linear Dynamics in BEP

1636

I. Koop, E. Perevedentsev
BINP SB RAS, Novosibirsk, Russia
T.V. Zolkin
University of Chicago, Chicago, Illinois, USA

An analysis of the dependence of experimental captured positron current data from the booster storage ring BEP (VEPP-2000 facility, BINP, Russia) on the working point position on the frequency map has uncovered a great number of different non-linear resonances. The number of captured positrons after a single injection is observed to be much less than the expected value. It is anticipated that the high degree of symmetry in the magnet system of BEP, however, should lead to the suppression of such resonances. To study this discrepancy, numerical simulations of positron beam movement under different perturbations to account for potential errors in magnetic field gradient of non-linear elements and errors in their angular location are used. The findings of this research provide qualitative explanations of the experimental work diagram and answers to two main questions, specifically “Why in the absence of skew-sextupoles in structure and small coupling are strong skew-sextupole resonances observed” and “Why skew-sextupole resonances are stronger than sextupole ones of the same harmonic”. A comparison between simulation results and analytical estimates is also presented.