BAGELS for simultaneous polarization, orbit, and optics control in electron storage rings

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Signorelli, M. G., Hoffstaetter, G. H.
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866912154883457024
author Signorelli, M. G.
Hoffstaetter, G. H.
author_facet Signorelli, M. G.
Hoffstaetter, G. H.
contents We present a new method for minimizing the effects of radiative depolarization in electron storage rings by use of a minimal number of special vertical orbit bumps. The bumps can be used to minimize the effects of radiative depolarization while simultaneously maintaining other common benefits of vertical orbits, e.g. transverse coupling and vertical dispersion control. Because simultaneously optimizing the large number of vertical correctors in a ring is operationally infeasible, we use dimensionality reduction to define a minimal number of most effective groups of vertical correctors that can be optimized during operation, motivating the name ``Best Adjustment Groups for ELectron Spin'' (BAGELS). The method is streamlined by using suitable ``basis bumps'' instead of all individual vertical correctors. We define three types of basis bumps for different purposes: (1) generates no delocalized transverse coupling nor delocalized vertical dispersion, (2) generates no delocalized vertical dispersion, and (3) generates no delocalized transverse coupling. BAGELS has been essential in the design of the Electron Storage Ring (ESR) of the Electron-Ion Collider (EIC), and will be beneficial for any polarized electron ring, including FCC-ee. HERA and LEP would have likely benefitted as well. We use BAGELS to significantly increase polarization in the 18 GeV EIC-ESR, beyond achievable with conventional methods; in the 1-IP lattice, we nearly double the asymptotic polarization, and in the 2-IP lattice we more than triple the asymptotic polarization. We also use BAGELS to construct knobs that can be used for global coupling correction, and knobs that generate vertical emittance for beam size matching, all while having minimal impacts on the polarization and orbit/optics.
format Preprint
id arxiv_https___arxiv_org_abs_2412_10195
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle BAGELS for simultaneous polarization, orbit, and optics control in electron storage rings
Signorelli, M. G.
Hoffstaetter, G. H.
Accelerator Physics
We present a new method for minimizing the effects of radiative depolarization in electron storage rings by use of a minimal number of special vertical orbit bumps. The bumps can be used to minimize the effects of radiative depolarization while simultaneously maintaining other common benefits of vertical orbits, e.g. transverse coupling and vertical dispersion control. Because simultaneously optimizing the large number of vertical correctors in a ring is operationally infeasible, we use dimensionality reduction to define a minimal number of most effective groups of vertical correctors that can be optimized during operation, motivating the name ``Best Adjustment Groups for ELectron Spin'' (BAGELS). The method is streamlined by using suitable ``basis bumps'' instead of all individual vertical correctors. We define three types of basis bumps for different purposes: (1) generates no delocalized transverse coupling nor delocalized vertical dispersion, (2) generates no delocalized vertical dispersion, and (3) generates no delocalized transverse coupling. BAGELS has been essential in the design of the Electron Storage Ring (ESR) of the Electron-Ion Collider (EIC), and will be beneficial for any polarized electron ring, including FCC-ee. HERA and LEP would have likely benefitted as well. We use BAGELS to significantly increase polarization in the 18 GeV EIC-ESR, beyond achievable with conventional methods; in the 1-IP lattice, we nearly double the asymptotic polarization, and in the 2-IP lattice we more than triple the asymptotic polarization. We also use BAGELS to construct knobs that can be used for global coupling correction, and knobs that generate vertical emittance for beam size matching, all while having minimal impacts on the polarization and orbit/optics.
title BAGELS for simultaneous polarization, orbit, and optics control in electron storage rings
topic Accelerator Physics
url https://arxiv.org/abs/2412.10195