CYCLOTRONS2022 - List of Keywords (permanent-magnet)

Paper	Title	Other Keywords	Page
MOPO014	Design Studies of the Cylindrically Symmetric Magnetic Inflector	injection, cyclotron, space-charge, simulation	87
	L.G. Zhang, R.A. Baartman, Y. Bylinskii, T. Planche, Y.-N. Rao TRIUMF, Vancouver, Canada
	The spiral inflector steers the beam from the bore in the main magnet into the median plane to achieve the axial injection with an external ion source. In a conventional electrostatic infector, the injection beam energy is limited by the breakdown voltage on the electrodes. At the same time, the injection intensity is also limited by the small aperture in the electrostatic inflector. Magnetic inflector is a promising alternative to overcome these disadvantages. To demonstrate the technology, we use the TR100 main magnet model, a conceptual idea of an H²⁺ cyclotron, as a testbench to study the inflection conditions and optics of the passive magnetic inflector with a cylindrically symmetric structure. A mirror-like field with optimized mirror length and ratio provides a well-focused beam arriving at the median plane. The required magnetic field is produced by shimming a center plug in the injection hole. The space charge effect is also discussed with the simulation of a high-intensity injection beam.
	Poster MOPO014 [0.678 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO014
About •	Received ※ 04 December 2022 — Revised ※ 01 February 2023 — Accepted ※ 06 February 2023 — Issue date ※ 04 March 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPO016	Design and Analysis of the 230 MeV Cyclotron Magnet for the Proton Therapy System	cyclotron, acceleration, proton, focusing	342
	X.H. Zhang CGN, Mianyang City, People’s Republic of China
	This paper introduces the design and analysis of 230 MeV cyclotron magnet of the proton therapy system. The magnet is an important part of the 230 MeV cyclotron, which can supply proton beam for the therapy terminal. The magnetic field calculation and modification has been done, and the isochronous error of the magnetic field is less than 0.2%. Meanwhile, the thermal analysis of the coil has been calculated by the empirical formula.
	Poster THPO016 [0.591 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO016
About •	Received ※ 02 February 2023 — Revised ※ 07 February 2023 — Accepted ※ 28 February 2023 — Issue date ※ 23 March 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRBI02	Design of a Spiral Inflector at iThemba LABS for Injecting the Beam into a Cyclotron	cyclotron, quadrupole, simulation, optics	373
	A.H. Barnard iThemba LABS, Somerset West, South Africa
	Funding: iThemba LABS Using a Belmont-Pabot spiral inflector for axial beam injection presents difficulties when matching the beam emittance to the cyclotron acceptance. For an electrostatic inflector one of the potential solutions to this problem is to use transverse electric field gradients to influence and optimise the optics. Here we extend this approach to magnetic spiral inflectors. It is demonstrated that the gradient of the magnetic field along the central trajectory can be controlled by an appropriate permanent magnet inflector design, and that these gradients have a large influence on the optics. The transverse gradients are numerically optimised and the performance compared to an optimised electrostatic spiral inflector. A faster numerical method for accurately determining the electric field of an electrostatic inflector is also presented.
	Slides FRBI02 [1.872 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-FRBI02
About •	Received ※ 31 December 2022 — Revised ※ 26 January 2023 — Accepted ※ 28 January 2023 — Issue date ※ 19 May 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPO014

Design Studies of the Cylindrically Symmetric Magnetic Inflector

injection, cyclotron, space-charge, simulation

87

L.G. Zhang, R.A. Baartman, Y. Bylinskii, T. Planche, Y.-N. Rao
TRIUMF, Vancouver, Canada

The spiral inflector steers the beam from the bore in the main magnet into the median plane to achieve the axial injection with an external ion source. In a conventional electrostatic infector, the injection beam energy is limited by the breakdown voltage on the electrodes. At the same time, the injection intensity is also limited by the small aperture in the electrostatic inflector. Magnetic inflector is a promising alternative to overcome these disadvantages. To demonstrate the technology, we use the TR100 main magnet model, a conceptual idea of an H²⁺ cyclotron, as a testbench to study the inflection conditions and optics of the passive magnetic inflector with a cylindrically symmetric structure. A mirror-like field with optimized mirror length and ratio provides a well-focused beam arriving at the median plane. The required magnetic field is produced by shimming a center plug in the injection hole. The space charge effect is also discussed with the simulation of a high-intensity injection beam.

Poster MOPO014 [0.678 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO014

About •

Received ※ 04 December 2022 — Revised ※ 01 February 2023 — Accepted ※ 06 February 2023 — Issue date ※ 04 March 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPO016

Design and Analysis of the 230 MeV Cyclotron Magnet for the Proton Therapy System

cyclotron, acceleration, proton, focusing

342

X.H. Zhang
CGN, Mianyang City, People’s Republic of China

This paper introduces the design and analysis of 230 MeV cyclotron magnet of the proton therapy system. The magnet is an important part of the 230 MeV cyclotron, which can supply proton beam for the therapy terminal. The magnetic field calculation and modification has been done, and the isochronous error of the magnetic field is less than 0.2%. Meanwhile, the thermal analysis of the coil has been calculated by the empirical formula.

Poster THPO016 [0.591 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO016

About •

Received ※ 02 February 2023 — Revised ※ 07 February 2023 — Accepted ※ 28 February 2023 — Issue date ※ 23 March 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRBI02

Design of a Spiral Inflector at iThemba LABS for Injecting the Beam into a Cyclotron

cyclotron, quadrupole, simulation, optics

373

A.H. Barnard
iThemba LABS, Somerset West, South Africa

Funding: iThemba LABS
Using a Belmont-Pabot spiral inflector for axial beam injection presents difficulties when matching the beam emittance to the cyclotron acceptance. For an electrostatic inflector one of the potential solutions to this problem is to use transverse electric field gradients to influence and optimise the optics. Here we extend this approach to magnetic spiral inflectors. It is demonstrated that the gradient of the magnetic field along the central trajectory can be controlled by an appropriate permanent magnet inflector design, and that these gradients have a large influence on the optics. The transverse gradients are numerically optimised and the performance compared to an optimised electrostatic spiral inflector. A faster numerical method for accurately determining the electric field of an electrostatic inflector is also presented.

Slides FRBI02 [1.872 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-FRBI02

About •

Received ※ 31 December 2022 — Revised ※ 26 January 2023 — Accepted ※ 28 January 2023 — Issue date ※ 19 May 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)