Cyclotrons2016 - List of Keywords (lattice)

Paper	Title	Other Keywords	Page
MOC01	Radiation Damage of Components in the Environment of High-Power Proton Accelerators	radiation, target, proton, simulation	24
	D.C. Kiselev, R.M. Bergmann, R. Sobbia, V. Talanov, M. Wohlmuther PSI, Villigen PSI, Switzerland
	At high power accelerators, radiation damage becomes an issue particularly for components which are hit directly by the beam, like targets and collimators. Protons and secondary particles change the microscopic (lattice) structure of the materials, which macroscopically affects physical and mechanical properties. Examples are the decrease of thermal conductivity and ductility as well as dimensional changes. However, the prediction of these damage effects and their evolution in this harsh environment is highly complex as they strongly depend on parameters such as the irradiation temperature of the material, and the energy and type of particle inducing the damage. The so-called term "displacements per atom" (DPA) is an attempt to quantify the amount of radiation induced damage and to compare the micro- and macroscopic effects of radiation damage caused by different particles at different energies. In this talk, the basics for understanding of the mechanisms of radiation damage will be explained. The definition and determination of DPA and its limitations will be discussed. Measurements and examples of the impact of radiation damage on accelerator components will be presented.
	Slides MOC01 [8.493 MB]
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUC02	Charge Stripper Ring for Cyclotron Cascade	acceleration, ion, cyclotron, heavy-ion	155
	H. Imao RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama, Japan N. Fukunishi, O. Kamigaito, M. Kase, H. Okuno, N. Sakamoto, K. Suda, K. Yamada, Y. Yano RIKEN Nishina Center, Wako, Japan
	In the multi-stage acceleration of heavy ions such as the acceleration at the RIKEN RI beam factory (RIBF), the electron stripping process with charge strippers is an inevitable process for the efficient acceleration. Typical efficiencies, however, for the charge-state conversion of very heavy ions are about 15-30% with common charge strippers. Actually, the total efficiency of two charge strippers for the uranium acceleration at the RIBF is only 6%. The low conversion efficiency is an important bottleneck for the intensity upgrade. Multi-charge acceleration proposed in the FRIB project is a unique method for linac to drastically increase the low conversion efficiency. The method, unfortunately, is not applicable for the ring accelerators such as cyclotrons. In the present study, we designed high-efficient charge stripper rings which have applicability to the cyclotron cascade using the technical knowledge of gas stripper recently developed at the RIBF.
	Slides TUC02 [5.544 MB]
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOC01

Radiation Damage of Components in the Environment of High-Power Proton Accelerators

radiation, target, proton, simulation

24

D.C. Kiselev, R.M. Bergmann, R. Sobbia, V. Talanov, M. Wohlmuther
PSI, Villigen PSI, Switzerland

At high power accelerators, radiation damage becomes an issue particularly for components which are hit directly by the beam, like targets and collimators. Protons and secondary particles change the microscopic (lattice) structure of the materials, which macroscopically affects physical and mechanical properties. Examples are the decrease of thermal conductivity and ductility as well as dimensional changes. However, the prediction of these damage effects and their evolution in this harsh environment is highly complex as they strongly depend on parameters such as the irradiation temperature of the material, and the energy and type of particle inducing the damage. The so-called term "displacements per atom" (DPA) is an attempt to quantify the amount of radiation induced damage and to compare the micro- and macroscopic effects of radiation damage caused by different particles at different energies. In this talk, the basics for understanding of the mechanisms of radiation damage will be explained. The definition and determination of DPA and its limitations will be discussed. Measurements and examples of the impact of radiation damage on accelerator components will be presented.

Slides MOC01 [8.493 MB]

Export •

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

TUC02

Charge Stripper Ring for Cyclotron Cascade

acceleration, ion, cyclotron, heavy-ion

155

H. Imao
RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama, Japan
N. Fukunishi, O. Kamigaito, M. Kase, H. Okuno, N. Sakamoto, K. Suda, K. Yamada, Y. Yano
RIKEN Nishina Center, Wako, Japan

In the multi-stage acceleration of heavy ions such as the acceleration at the RIKEN RI beam factory (RIBF), the electron stripping process with charge strippers is an inevitable process for the efficient acceleration. Typical efficiencies, however, for the charge-state conversion of very heavy ions are about 15-30% with common charge strippers. Actually, the total efficiency of two charge strippers for the uranium acceleration at the RIBF is only 6%. The low conversion efficiency is an important bottleneck for the intensity upgrade. Multi-charge acceleration proposed in the FRIB project is a unique method for linac to drastically increase the low conversion efficiency. The method, unfortunately, is not applicable for the ring accelerators such as cyclotrons. In the present study, we designed high-efficient charge stripper rings which have applicability to the cyclotron cascade using the technical knowledge of gas stripper recently developed at the RIBF.

Slides TUC02 [5.544 MB]

Export •

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