HB2023 - Table of Session: THA1I (Invited Presentations WG A)

Paper	Title	Page
THA1I1	Performance and Upgrade Considerations for the CSNS Injection	326
	M.Y. Huang, S. Wang, S.Y. Xu IHEP, Beijing, People’s Republic of China
	Funding: This work is jointly supported by the National Natural Science Foundation of China (Nos. 12075134) and the Guangdong Basic and Applied Basic Research Foundation (No. 2021B1515120021). For the proton synchrotron, the beam injection is one of the most important issues. Firstly, based on the China Spallation Neutron Source (CSNS), the injection methods have been comprehensively studied, including phase space painting and H⁻ stripping. In order to solve the key difficulties faced when the beam power exceeds 50% of the design value, flexibility in the CSNS design has been exploited to implement the correlated painting by using the rising current curve of the pulse power supply. The effectiveness of the new method has been verified in the simulation and beam commissioning. By using the new method, the beam power on the target has successfully risen to the design value. Secondly, for the CSNS upgrade, the injection energy is increased from 80 MeV to 300 MeV and the injection beam power is increased by about 19 times. Based on the CSNS experience and simulation results, it is hoped that the new injection scheme can not only be compatible with correlated and anti-correlated painting, but also greatly reduces the peak temperature of the stripping foil. After in-depth study, a new painting scheme has been proposed which has been verified to be feasible in the simulation.
	Slides THA1I1 [2.951 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THA1I1
About •	Received ※ 01 October 2023 — Revised ※ 06 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 15 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THA1I2	High-Intensity Studies on the ISIS RCS and Their Impact on the Design of ISIS-II	331
	R.E. Williamson, D.J. Adams, H.V. Cavanagh, B.S. Kyle, D.W. Posthuma de Boer, H. Rafique, C.M. Warsop STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	ISIS is the pulsed spallation neutron and muon source at the Rutherford Appleton Laboratory in the UK. Operation centres on a rapid cycling proton synchrotron (RCS) that accelerates 3·10¹³ protons per pulse from 70 MeV to 800 MeV at 50 Hz, delivering a mean beam power of 0.2 MW. As a high-intensity machine, research at ISIS is predominantly focused on understanding, minimising and controlling beam-loss, which is central to sustainable machine operation. Knowledge of beam-loss mechanisms then informs the design of future high power accelerators such as ISIS-II. This paper provides an overview of the R&D studies currently underway on the ISIS RCS and how these relate to ongoing work understanding and optimising designs for ISIS-II. In particular, recent extensive investigations into observed head-tail instabilities are summarised.
	Slides THA1I2 [10.825 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THA1I2
About •	Received ※ 01 October 2023 — Revised ※ 07 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 18 October 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THA1I3	Predominantly Electric Storage Ring with Nuclear Spin Control Capability	338
	R.M. Talman Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	A predominantly electric storage ring with weak superimposed magnetic bending is shown to be capable of storing two different nuclear isotope bunches, such as helion and deuteron, co-traveling with different velocities on the same central orbit. ‘‘Rear-end’’ collisions occurring periodically in a full acceptance particle detector/polarimeter, allow the (previously inaccessible) direct measurement of the spin dependence of nuclear transmutation for center of mass (CM) kinetic energies ranging from hundreds of keV up toward pion production thresholds. These are ‘‘rear-end collisions’’ occurring as faster stored bunches pass through slower bunches. An inexpensive facility capable of meeting these requirements is described, with nuclear channel h + d arrow α + p as example.
	Slides THA1I3 [0.860 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-HB2023-THA1I3
About •	Received ※ 07 December 2023 — Accepted ※ 11 December 2023 — Issued ※ 25 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Performance and Upgrade Considerations for the CSNS Injection

326

M.Y. Huang, S. Wang, S.Y. Xu
IHEP, Beijing, People’s Republic of China

Funding: This work is jointly supported by the National Natural Science Foundation of China (Nos. 12075134) and the Guangdong Basic and Applied Basic Research Foundation (No. 2021B1515120021).
For the proton synchrotron, the beam injection is one of the most important issues. Firstly, based on the China Spallation Neutron Source (CSNS), the injection methods have been comprehensively studied, including phase space painting and H⁻ stripping. In order to solve the key difficulties faced when the beam power exceeds 50% of the design value, flexibility in the CSNS design has been exploited to implement the correlated painting by using the rising current curve of the pulse power supply. The effectiveness of the new method has been verified in the simulation and beam commissioning. By using the new method, the beam power on the target has successfully risen to the design value. Secondly, for the CSNS upgrade, the injection energy is increased from 80 MeV to 300 MeV and the injection beam power is increased by about 19 times. Based on the CSNS experience and simulation results, it is hoped that the new injection scheme can not only be compatible with correlated and anti-correlated painting, but also greatly reduces the peak temperature of the stripping foil. After in-depth study, a new painting scheme has been proposed which has been verified to be feasible in the simulation.

Slides THA1I1 [2.951 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THA1I1

About •

Received ※ 01 October 2023 — Revised ※ 06 October 2023 — Accepted ※ 09 October 2023 — Issued ※ 15 October 2023

Cite •

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

THA1I2

High-Intensity Studies on the ISIS RCS and Their Impact on the Design of ISIS-II

331

R.E. Williamson, D.J. Adams, H.V. Cavanagh, B.S. Kyle, D.W. Posthuma de Boer, H. Rafique, C.M. Warsop
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

ISIS is the pulsed spallation neutron and muon source at the Rutherford Appleton Laboratory in the UK. Operation centres on a rapid cycling proton synchrotron (RCS) that accelerates 3·10¹³ protons per pulse from 70 MeV to 800 MeV at 50 Hz, delivering a mean beam power of 0.2 MW. As a high-intensity machine, research at ISIS is predominantly focused on understanding, minimising and controlling beam-loss, which is central to sustainable machine operation. Knowledge of beam-loss mechanisms then informs the design of future high power accelerators such as ISIS-II. This paper provides an overview of the R&D studies currently underway on the ISIS RCS and how these relate to ongoing work understanding and optimising designs for ISIS-II. In particular, recent extensive investigations into observed head-tail instabilities are summarised.

Slides THA1I2 [10.825 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THA1I2

About •

Received ※ 01 October 2023 — Revised ※ 07 October 2023 — Accepted ※ 10 October 2023 — Issued ※ 18 October 2023

Cite •

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

THA1I3

Predominantly Electric Storage Ring with Nuclear Spin Control Capability

338

R.M. Talman
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

A predominantly electric storage ring with weak superimposed magnetic bending is shown to be capable of storing two different nuclear isotope bunches, such as helion and deuteron, co-traveling with different velocities on the same central orbit. ‘‘Rear-end’’ collisions occurring periodically in a full acceptance particle detector/polarimeter, allow the (previously inaccessible) direct measurement of the spin dependence of nuclear transmutation for center of mass (CM) kinetic energies ranging from hundreds of keV up toward pion production thresholds. These are ‘‘rear-end collisions’’ occurring as faster stored bunches pass through slower bunches. An inexpensive facility capable of meeting these requirements is described, with nuclear channel h + d arrow α + p as example.

Slides THA1I3 [0.860 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-HB2023-THA1I3

About •

Received ※ 07 December 2023 — Accepted ※ 11 December 2023 — Issued ※ 25 December 2023

Cite •

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