IPAC2021 - Classification: MC1: Circular and Linear Colliders / A24 Accelerators and Storage Rings, Other

Paper	Title	Page
WEPAB011	Update on the Low Emittance Tuning of the e⁺/e^- Future Circular Collider	2601
	T.K. Charles The University of Liverpool, Liverpool, United Kingdom B.J. Holzer, F. Zimmermann CERN, Geneva, Switzerland K. Oide KEK, Ibaraki, Japan
	The FCC-ee project studies the design of a future 100 km e+/e circular collider for precision studies and rare decay observations in the range of 90 to 350 GeV center of mass energy with luminosities in the order of 10³⁵ cm^-2 s⁻¹. To achieve ultra-low vertical emittance a highly effective emittance tuning scheme is required. In this paper, we describe a comprehensive correction strategy used for the low emittance tuning. The strategy includes Dispersion Free Steering, linear coupling compensation based on Resonant Driving Terms and beta beat correction utilising response matrices.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB011
About •	paper received ※ 18 May 2021 paper accepted ※ 23 June 2021 issue date ※ 02 September 2021
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WEPAB013	A New Algorithm for Positron Source Parameter Optimisation	2609
	Y. Zhao, L. Ma SDU, Shandong, People’s Republic of China S. Döbert, A. Latina CERN, Geneva, Switzerland
	In this report, we proposed a new simple and efficient algorithm for positron source parameter optimisation, which is based on iterations of scan of free parameters in the simulation. The new algorithm is fast, simple and convincing since the results can be visually drawn and flexibly tuned and it has an advantage that it can easily handle realistic parametric problems with more than one objective quantities to optimise. The optimisation of the main parameters of the CLIC positron source at the 380 GeV stage is presented as an example to demonstrate how the algorithm works.
	Poster WEPAB013 [1.352 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB013
About •	paper received ※ 15 May 2021 paper accepted ※ 24 June 2021 issue date ※ 17 August 2021
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WEPAB014	Optimisation of the CLIC Positron Source	2613
	Y. Zhao, L. Ma SDU, Shandong, People’s Republic of China H.M.A. Bajas, S. Döbert, A. Latina CERN, Geneva, Switzerland
	In this report, we reoptimised the CLIC positron source at all collision energy stages. Simulation, optimisation algorithm and results were all improved compared with previous studies. Two different target schemes were studied and compared in terms of the advantages and disadvantages. The spot size of the injected electron beam was also optimised to achieve a compromise between large positron yields and safe energy deposition. The matching device for the capture of positrons was simulated and optimised with both improved analytic and realistic field maps. Conical aperture and front and rear gaps of the matching device were also considered for the first time. The optimised positron source is expected to have the lowest cost.
	Poster WEPAB014 [1.825 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB014
About •	paper received ※ 15 May 2021 paper accepted ※ 21 June 2021 issue date ※ 25 August 2021
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WEPAB015	Comparison of Different Matching Device Field Profiles for the FCC-ee Positron Source	2617
	Y. Zhao, L. Ma SDU, Shandong, People’s Republic of China B. Auchmann, P. Craievich, J. Kosse, R. Zennaro PSI, Villigen PSI, Switzerland I. Chaikovska, R. Chehab Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France S. Döbert, A. Latina CERN, Meyrin, Switzerland P.V. Martyshkin BINP SB RAS, Novosibirsk, Russia
	In this report, we compared different matching device field profiles for the FCC-ee positron source. The matching device is used to capture positrons with magnetic field. A flux concentrator was designed with a conical inner chamber. A smaller aperture and a larger aperture were studied. An analytic field profile was also studied using an adiabatic formula. The peak field of the analytic profile as well as beam and target parameters was optimised to achieve a maximum positron yield. A safe energy deposition in the target was guaranteed by requiring a constraint on the deposited power and peak energy deposition density.
	Poster WEPAB015 [3.066 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB015
About •	paper received ※ 15 May 2021 paper accepted ※ 23 June 2021 issue date ※ 30 August 2021
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WEPAB016	Snowmass’21 Accelerator Frontier	2621
	V.D. Shiltsev Fermilab, Batavia, Illinois, USA S.A. Gourlay LBNL, Berkeley, California, USA T.O. Raubenheimer SLAC, Menlo Park, California, USA
	Snowmass’21 is decadal particle physics community planning study. It provides an opportunity for the entire particle physics community to come together to identify and document a scientific vision for the future of particle physics in the U.S. and its international partners. Snowmass will define the most important questions for the field of particle physics and identify promising opportunities to address them. The P5, Particle Physics Project Prioritization Panel, will take the scientific input from Snowmass and develop a strategic plan for U.S. particle physics that can be executed over a 10 year timescale, in the context of a 20-year global vision for the field. Here we present the goals, progress and plans of the Snowmass’21 Accelerator Frontier.
	Poster WEPAB016 [1.108 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB016
About •	paper received ※ 17 May 2021 paper accepted ※ 23 June 2021 issue date ※ 12 August 2021
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WEPAB017	General Approach to Physics Limits of Ultimate Colliders	2624
	V.D. Shiltsev Fermilab, Batavia, Illinois, USA
	The future of the particle physics is critically dependent on feasibility of future energy frontier colliders. The concept of the feasibility is complex and includes at least three factors: feasibility of energy, feasibility of luminosity, and feasibility of cost and construction time. Here we discuss major beam physics limits of ultimate accelerators, take a look into ultimate energy reach of possible future colliders. We also foresee a looming paradigm change for the HEP research as the thrust for higher energies by necessity will mean lower luminosity.
	Poster WEPAB017 [1.720 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB017
About •	paper received ※ 19 May 2021 paper accepted ※ 24 June 2021 issue date ※ 17 August 2021
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THPAB147	Preliminary Study of 500 MHz HOM-Free RF Cavity	4050
	Zh.X. Tang USTC/NSRL, Hefei, Anhui, People’s Republic of China
	Funding: Work supported by National Natural Science Foundation of China(Grant No. U1832135 and 11805199)} In this paper, we study the microwave characteristics of 500 MHz RF cavity, including the optimization of cavity structure, the simulation design of high-order mode (HOM) absorption structure and the design of coupler. The cavity structure is simulated by CST. The absorption waveguide is designed and optimized. The coupler is designed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB147
About •	paper received ※ 09 May 2021 paper accepted ※ 16 July 2021 issue date ※ 02 September 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Update on the Low Emittance Tuning of the e⁺/e^- Future Circular Collider

2601

T.K. Charles
The University of Liverpool, Liverpool, United Kingdom
B.J. Holzer, F. Zimmermann
CERN, Geneva, Switzerland
K. Oide
KEK, Ibaraki, Japan

The FCC-ee project studies the design of a future 100 km e+/e circular collider for precision studies and rare decay observations in the range of 90 to 350 GeV center of mass energy with luminosities in the order of 10³⁵ cm^-2 s⁻¹. To achieve ultra-low vertical emittance a highly effective emittance tuning scheme is required. In this paper, we describe a comprehensive correction strategy used for the low emittance tuning. The strategy includes Dispersion Free Steering, linear coupling compensation based on Resonant Driving Terms and beta beat correction utilising response matrices.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB011

About •

paper received ※ 18 May 2021 paper accepted ※ 23 June 2021 issue date ※ 02 September 2021

Export •

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

WEPAB013

A New Algorithm for Positron Source Parameter Optimisation

2609

Y. Zhao, L. Ma
SDU, Shandong, People’s Republic of China
S. Döbert, A. Latina
CERN, Geneva, Switzerland

In this report, we proposed a new simple and efficient algorithm for positron source parameter optimisation, which is based on iterations of scan of free parameters in the simulation. The new algorithm is fast, simple and convincing since the results can be visually drawn and flexibly tuned and it has an advantage that it can easily handle realistic parametric problems with more than one objective quantities to optimise. The optimisation of the main parameters of the CLIC positron source at the 380 GeV stage is presented as an example to demonstrate how the algorithm works.

Poster WEPAB013 [1.352 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB013

About •

paper received ※ 15 May 2021 paper accepted ※ 24 June 2021 issue date ※ 17 August 2021

Export •

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

WEPAB014

Optimisation of the CLIC Positron Source

2613

Y. Zhao, L. Ma
SDU, Shandong, People’s Republic of China
H.M.A. Bajas, S. Döbert, A. Latina
CERN, Geneva, Switzerland

In this report, we reoptimised the CLIC positron source at all collision energy stages. Simulation, optimisation algorithm and results were all improved compared with previous studies. Two different target schemes were studied and compared in terms of the advantages and disadvantages. The spot size of the injected electron beam was also optimised to achieve a compromise between large positron yields and safe energy deposition. The matching device for the capture of positrons was simulated and optimised with both improved analytic and realistic field maps. Conical aperture and front and rear gaps of the matching device were also considered for the first time. The optimised positron source is expected to have the lowest cost.

Poster WEPAB014 [1.825 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB014

About •

paper received ※ 15 May 2021 paper accepted ※ 21 June 2021 issue date ※ 25 August 2021

Export •

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

WEPAB015

Comparison of Different Matching Device Field Profiles for the FCC-ee Positron Source

2617

Y. Zhao, L. Ma
SDU, Shandong, People’s Republic of China
B. Auchmann, P. Craievich, J. Kosse, R. Zennaro
PSI, Villigen PSI, Switzerland
I. Chaikovska, R. Chehab
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
S. Döbert, A. Latina
CERN, Meyrin, Switzerland
P.V. Martyshkin
BINP SB RAS, Novosibirsk, Russia

In this report, we compared different matching device field profiles for the FCC-ee positron source. The matching device is used to capture positrons with magnetic field. A flux concentrator was designed with a conical inner chamber. A smaller aperture and a larger aperture were studied. An analytic field profile was also studied using an adiabatic formula. The peak field of the analytic profile as well as beam and target parameters was optimised to achieve a maximum positron yield. A safe energy deposition in the target was guaranteed by requiring a constraint on the deposited power and peak energy deposition density.

Poster WEPAB015 [3.066 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB015

About •

paper received ※ 15 May 2021 paper accepted ※ 23 June 2021 issue date ※ 30 August 2021

Export •

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

WEPAB016

Snowmass’21 Accelerator Frontier

2621

V.D. Shiltsev
Fermilab, Batavia, Illinois, USA
S.A. Gourlay
LBNL, Berkeley, California, USA
T.O. Raubenheimer
SLAC, Menlo Park, California, USA

Snowmass’21 is decadal particle physics community planning study. It provides an opportunity for the entire particle physics community to come together to identify and document a scientific vision for the future of particle physics in the U.S. and its international partners. Snowmass will define the most important questions for the field of particle physics and identify promising opportunities to address them. The P5, Particle Physics Project Prioritization Panel, will take the scientific input from Snowmass and develop a strategic plan for U.S. particle physics that can be executed over a 10 year timescale, in the context of a 20-year global vision for the field. Here we present the goals, progress and plans of the Snowmass’21 Accelerator Frontier.

Poster WEPAB016 [1.108 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB016

About •

paper received ※ 17 May 2021 paper accepted ※ 23 June 2021 issue date ※ 12 August 2021

Export •

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

WEPAB017

General Approach to Physics Limits of Ultimate Colliders

2624

V.D. Shiltsev
Fermilab, Batavia, Illinois, USA

The future of the particle physics is critically dependent on feasibility of future energy frontier colliders. The concept of the feasibility is complex and includes at least three factors: feasibility of energy, feasibility of luminosity, and feasibility of cost and construction time. Here we discuss major beam physics limits of ultimate accelerators, take a look into ultimate energy reach of possible future colliders. We also foresee a looming paradigm change for the HEP research as the thrust for higher energies by necessity will mean lower luminosity.

Poster WEPAB017 [1.720 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB017

About •

paper received ※ 19 May 2021 paper accepted ※ 24 June 2021 issue date ※ 17 August 2021

Export •

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

THPAB147

Preliminary Study of 500 MHz HOM-Free RF Cavity

4050

Zh.X. Tang
USTC/NSRL, Hefei, Anhui, People’s Republic of China

Funding: Work supported by National Natural Science Foundation of China(Grant No. U1832135 and 11805199)}
In this paper, we study the microwave characteristics of 500 MHz RF cavity, including the optimization of cavity structure, the simulation design of high-order mode (HOM) absorption structure and the design of coupler. The cavity structure is simulated by CST. The absorption waveguide is designed and optimized. The coupler is designed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB147

About •

paper received ※ 09 May 2021 paper accepted ※ 16 July 2021 issue date ※ 02 September 2021

Export •

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