IPAC2022 - List of Authors (Ramoisiaux, E.)

Paper	Title	Page
MOPOST027	The Zgoubidoo Python Framework for Ray-Tracing Simulations with Zgoubi: Applications to Fixed-Field Accelerators	118
SUSPMF043	use link to see paper's listing under its alternate paper code
	M. Vanwelde, E. Gnacadja, C. Hernalsteens, N. Pauly, E. Ramoisiaux, R. Tesse ULB, Bruxelles, Belgium C. Hernalsteens CERN, Meyrin, Switzerland
	The study of beam dynamics in accelerators featuring main magnets with complex geometries such as Fixed Field Accelerators (FFAs) requires simulation codes allowing step-by-step particle tracking in complex magnetic fields, such as the Zgoubi ray-tracing code. To facilitate the use of Zgoubi and to allow readily processing the resulting tracking data, we developed a modern Python 3 interface, Zgoubidoo, using Zgoubi in the backend. In this work, the key features of Zgoubidoo are illustrated by detailing the main steps to obtain a non-scaling FFA accelerator from a scaling design. The results obtained are in excellent agreement with prior results, including the tune computation and orbit shifts. These results are enhanced by Zgoubidoo beam dynamics analysis and visualization tools, including the placement of lattice elements in a global coordinate system and the computation of linear step-by-step optics. The validation of Zgoubidoo on conventional scaling and non-scaling FFA designs paves the way for future uses in innovative FFA design studies.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST027
About •	Received ※ 16 May 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS041	Concrete Shielding Activation for Proton Therapy Systems Using BDSIM and FISPACT-II	728
SUSPMF096	use link to see paper's listing under its alternate paper code
	E. Ramoisiaux, E. Gnacadja, C. Hernalsteens, N. Pauly, R. Tesse, M. Vanwelde ULB, Bruxelles, Belgium C. Hernalsteens CERN, Meyrin, Switzerland F. Stichelbaut IBA, Louvain-la-Neuve, Belgium
	Proton therapy systems are used worldwide for patient treatment and fundamental research. The generation of secondary particles when the beam interacts with the beamline elements is a well-known issue. In particular, the energy degrader is the dominant source of secondary radiation. This poses new challenges for the concrete shielding of compact systems and beamline elements activation computation. We use a novel methodology to seamlessly simulate all the processes relevant to the activation evaluation. A realistic model of the system is developed using Beam Delivery Simulation (BDSIM), a Geant4-based particle tracking code that allows a single model to simulate primary and secondary particle tracking and all particle-matter interactions. The secondary particle fluxes extracted from the simulations are provided as input to FISPACT-II to compute the activation by solving the rate equations. This approach is applied to the Ion Beam Applications (IBA) Proteus®ONE (P1) system and the shielding of the proton therapy research centre of Charleroi, Belgium. Proton loss distributions are used to model the production of secondary neutrals inside the accelerator structure. Two models for the distribution of proton losses are compared for the computation of the clearance index at specific locations of the design. Results show that the variation in the accelerator loss models can be characterised as a systematic error.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS041
About •	Received ※ 19 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 22 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS003	Upgrade of a Proton Therapy Eye Treatment Nozzle Using a Cylindrical Beam Stopping Device for Enhanced Dose Rate Performances	2937
SUSPMF124	use link to see paper's listing under its alternate paper code
	E. Gnacadja, C. Hernalsteens, N. Pauly, E. Ramoisiaux, R. Tesse, M. Vanwelde ULB, Bruxelles, Belgium C. Hernalsteens CERN, Meyrin, Switzerland
	Proton therapy is a well established treatment method for ocular cancerous diseases. General-purpose multi-room systems which comprise eye-treatment beamlines must be thoroughly optimized to achieve the performances of fully dedicated systems in terms of depth-dose distal fall-off, lateral penumbra, and dose rate. For eye-treatment beamlines, the dose rate is one of the most critical clinical performances, as it directly defines the delivery time of a given treatment session. This delivery time must be kept as low as possible to reduce uncertainties due to undesired patient movement. We propose an alternative design of the Ion Beam Applications (IBA) Proteus Plus (P+) eye treatment beamline, which combines a beam-stopping device with the already existing scattering features of the beamline. The design is modelled with Beam Delivery SIMulation (BDSIM), a Geant4-based particle tracking and beam-matter interactions Monte-Carlo code, to demonstrate that it increases the maximum achievable dose rate by up to a factor §I{3} compared to the baseline configuration. An in-depth study of the system is performed and the resulting dosimetric properties are discussed in detail.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS003
About •	Received ※ 20 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS004	Achromatic Gantry Design Using Fixed-Field Spiral Combined-Function Magnets	2941
	R. Tesse, E. Gnacadja, C. Hernalsteens, N. Pauly, E. Ramoisiaux, M. Vanwelde ULB, Bruxelles, Belgium C. Hernalsteens CERN, Meyrin, Switzerland
	Arc-therapy and flash therapy are promising proton therapy treatment modalities as they enable further sparing of the healthy tissues surrounding the tumor site. They impose strong constraints on the beam delivery system and rotating gantry structure, in particular in providing high dose rate and fast energy scanning. Fixed-field achromatic transport lattices potentially satisfy both constraints in allowing instant energy modulation and sufficient transmission efficiency while providing a compact footprint. The presented design study uses fixed-field magnets with spiral edges respecting the FFA scaling law. The cell structure and the layout are studied in simulation and integrated in a compact gantry. Results and further optimizations are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS004
About •	Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 26 June 2022 — Issue date ※ 11 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

MOPOST027

The Zgoubidoo Python Framework for Ray-Tracing Simulations with Zgoubi: Applications to Fixed-Field Accelerators

118

SUSPMF043

use link to see paper's listing under its alternate paper code

M. Vanwelde, E. Gnacadja, C. Hernalsteens, N. Pauly, E. Ramoisiaux, R. Tesse
ULB, Bruxelles, Belgium
C. Hernalsteens
CERN, Meyrin, Switzerland

The study of beam dynamics in accelerators featuring main magnets with complex geometries such as Fixed Field Accelerators (FFAs) requires simulation codes allowing step-by-step particle tracking in complex magnetic fields, such as the Zgoubi ray-tracing code. To facilitate the use of Zgoubi and to allow readily processing the resulting tracking data, we developed a modern Python 3 interface, Zgoubidoo, using Zgoubi in the backend. In this work, the key features of Zgoubidoo are illustrated by detailing the main steps to obtain a non-scaling FFA accelerator from a scaling design. The results obtained are in excellent agreement with prior results, including the tune computation and orbit shifts. These results are enhanced by Zgoubidoo beam dynamics analysis and visualization tools, including the placement of lattice elements in a global coordinate system and the computation of linear step-by-step optics. The validation of Zgoubidoo on conventional scaling and non-scaling FFA designs paves the way for future uses in innovative FFA design studies.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST027

About •

Received ※ 16 May 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022

Cite •

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

MOPOMS041

Concrete Shielding Activation for Proton Therapy Systems Using BDSIM and FISPACT-II

728

SUSPMF096

use link to see paper's listing under its alternate paper code

E. Ramoisiaux, E. Gnacadja, C. Hernalsteens, N. Pauly, R. Tesse, M. Vanwelde
ULB, Bruxelles, Belgium
C. Hernalsteens
CERN, Meyrin, Switzerland
F. Stichelbaut
IBA, Louvain-la-Neuve, Belgium

Proton therapy systems are used worldwide for patient treatment and fundamental research. The generation of secondary particles when the beam interacts with the beamline elements is a well-known issue. In particular, the energy degrader is the dominant source of secondary radiation. This poses new challenges for the concrete shielding of compact systems and beamline elements activation computation. We use a novel methodology to seamlessly simulate all the processes relevant to the activation evaluation. A realistic model of the system is developed using Beam Delivery Simulation (BDSIM), a Geant4-based particle tracking code that allows a single model to simulate primary and secondary particle tracking and all particle-matter interactions. The secondary particle fluxes extracted from the simulations are provided as input to FISPACT-II to compute the activation by solving the rate equations. This approach is applied to the Ion Beam Applications (IBA) Proteus®ONE (P1) system and the shielding of the proton therapy research centre of Charleroi, Belgium. Proton loss distributions are used to model the production of secondary neutrals inside the accelerator structure. Two models for the distribution of proton losses are compared for the computation of the clearance index at specific locations of the design. Results show that the variation in the accelerator loss models can be characterised as a systematic error.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS041

About •

Received ※ 19 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 22 June 2022

Cite •

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

THPOMS003

Upgrade of a Proton Therapy Eye Treatment Nozzle Using a Cylindrical Beam Stopping Device for Enhanced Dose Rate Performances

2937

SUSPMF124

use link to see paper's listing under its alternate paper code

E. Gnacadja, C. Hernalsteens, N. Pauly, E. Ramoisiaux, R. Tesse, M. Vanwelde
ULB, Bruxelles, Belgium
C. Hernalsteens
CERN, Meyrin, Switzerland

Proton therapy is a well established treatment method for ocular cancerous diseases. General-purpose multi-room systems which comprise eye-treatment beamlines must be thoroughly optimized to achieve the performances of fully dedicated systems in terms of depth-dose distal fall-off, lateral penumbra, and dose rate. For eye-treatment beamlines, the dose rate is one of the most critical clinical performances, as it directly defines the delivery time of a given treatment session. This delivery time must be kept as low as possible to reduce uncertainties due to undesired patient movement. We propose an alternative design of the Ion Beam Applications (IBA) Proteus Plus (P+) eye treatment beamline, which combines a beam-stopping device with the already existing scattering features of the beamline. The design is modelled with Beam Delivery SIMulation (BDSIM), a Geant4-based particle tracking and beam-matter interactions Monte-Carlo code, to demonstrate that it increases the maximum achievable dose rate by up to a factor §I{3} compared to the baseline configuration. An in-depth study of the system is performed and the resulting dosimetric properties are discussed in detail.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS003

About •

Received ※ 20 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022

Cite •

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

THPOMS004

Achromatic Gantry Design Using Fixed-Field Spiral Combined-Function Magnets

2941

R. Tesse, E. Gnacadja, C. Hernalsteens, N. Pauly, E. Ramoisiaux, M. Vanwelde
ULB, Bruxelles, Belgium
C. Hernalsteens
CERN, Meyrin, Switzerland

Arc-therapy and flash therapy are promising proton therapy treatment modalities as they enable further sparing of the healthy tissues surrounding the tumor site. They impose strong constraints on the beam delivery system and rotating gantry structure, in particular in providing high dose rate and fast energy scanning. Fixed-field achromatic transport lattices potentially satisfy both constraints in allowing instant energy modulation and sufficient transmission efficiency while providing a compact footprint. The presented design study uses fixed-field magnets with spiral edges respecting the FFA scaling law. The cell structure and the layout are studied in simulation and integrated in a compact gantry. Results and further optimizations are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS004

About •

Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 26 June 2022 — Issue date ※ 11 July 2022

Cite •

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