IPAC2021 - List of Keywords (RF-structure)

Paper	Title	Other Keywords	Page
MOPAB355	Multi-Objective Optimization of RF Structures	cavity, impedance, controls, ECR	1103
	S.J. Smith, R. Apsimon, G. Burt, M.J.W. Southerby Cockcroft Institute, Lancaster University, Lancaster, United Kingdom S. Setiniyaz Cockcroft Institute, Warrington, Cheshire, United Kingdom S. Setiniyaz Lancaster University, Lancaster, United Kingdom
	In this work, we apply multi-objective optimization methods to single-cell cavity models generated using non-uniform rational basis splines (NURBS). This modeling method uses control points and a NURBS to generate the cavity geometry, which allows for greater flexibility in the shape, leading to improved performance. Using this approach and multi-objective genetic algorithms (MOGAs) we find the Pareto frontiers for the typical key quantities of interest (QoI) including peak fields, shunt impedance and the modified Poynting vector. Visualizing these results becomes increasingly more difficult as the number of objectives increases, therefore, in order to understand these frontiers, we provide several techniques for analyzing, visualizing and using multi-dimensional Pareto fronts specifically for RF cavity design.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB355
About •	paper received ※ 19 May 2021 paper accepted ※ 15 July 2021 issue date ※ 30 August 2021
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MOPAB371	A Coupon Tester for Normal Conducting High-Gradient Materials	cavity, coupling, vacuum, klystron	1147
	J.W. Lewellen, D. Gorelov, D. Perez, E.I. Simakov LANL, Los Alamos, New Mexico, USA M.E. Schneider Michigan State University, East Lansing, Michigan, USA
	Funding: Los Alamos National Laboratory LDRD Program A coupon tester is an RF structure used to subject a material sample to very high RF fields, with the fields on the sample, or coupon, being higher than elsewhere in the cavity. To date, most such cavities were originally intended to explore the RF properties of superconducting materials, and can expose the sample to strong magnetic fields, but weak to no electric fields. As part of a program to develop materials and structures for high-gradient (> 100 MV/m), low-breakdown-rate normal-conducting accelerators, we have designed a C-band (5.712 GHz) cavity intended to subject samples to both magnetic and electric fields comparable to those experienced in high-gradient structure designs, using a TM-mode cavity; the electric and magnetic fields along the sample coupon can be directly compared to the fields on the iris of high-gradient structures. This poster will present the design criteria for our coupon tester cavity, nominal operating parameters, and our structure concept. The cavity design will be refined over the next several months, and will be constructed and in service near the start of 2022.
	Poster MOPAB371 [0.764 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB371
About •	paper received ※ 17 May 2021 paper accepted ※ 26 May 2021 issue date ※ 30 August 2021
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WEPAB295	Parameter Estimation of Short Pulse Normal-Conducting Standing Wave Cavities	cavity, gun, coupling, resonance	3351
	S. Pfeiffer, J. Branlard, F. Burkart, M. Hoffmann, H. Schlarb DESY, Hamburg, Germany
	The linear accelerator ARES (Accelerator Research Experiment at SINBAD) is a new research facility at DESY. Electron bunches with a maximum repetition rate of 50 Hz are accelerated to a target energy of 155 MeV. The facility aims for ultra-stable sub-femtosecond arrival-times and high peak-currents at the experiment, placing high demands on the reference distribution and field regulation of the RF structure. In this contribution, we present the physical parameter estimation of key RF properties such as cavity detuning not directly measurable on the RF field decay. The method can be used as a fast monitor of inner cell temperature. The estimated properties are finally compared with the measured ones.
	Poster WEPAB295 [0.860 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB295
About •	paper received ※ 19 May 2021 paper accepted ※ 05 July 2021 issue date ※ 26 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPAB223	Energy Compression System Radio Frequency Design at the Canadian Light Source	linac, impedance, GUI, simulation	4231
	E.J. Ericson, D. Bertwistle, M.J. Boland CLS, Saskatoon, Saskatchewan, Canada
	The Canadian Light Source (CLS), Canada’s only synchrotron light source, is considering a linear accelerator (LINAC) upgrade. As a result, the radio frequency (RF) structure in the downstream Energy Compression System (ECS) needs to be redesigned. In this paper, we describe the design process followed to determine the geometry of the RF structure cells and coupler.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB223
About •	paper received ※ 18 May 2021 paper accepted ※ 28 July 2021 issue date ※ 28 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPAB355

Multi-Objective Optimization of RF Structures

cavity, impedance, controls, ECR

1103

S.J. Smith, R. Apsimon, G. Burt, M.J.W. Southerby
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
S. Setiniyaz
Cockcroft Institute, Warrington, Cheshire, United Kingdom
S. Setiniyaz
Lancaster University, Lancaster, United Kingdom

In this work, we apply multi-objective optimization methods to single-cell cavity models generated using non-uniform rational basis splines (NURBS). This modeling method uses control points and a NURBS to generate the cavity geometry, which allows for greater flexibility in the shape, leading to improved performance. Using this approach and multi-objective genetic algorithms (MOGAs) we find the Pareto frontiers for the typical key quantities of interest (QoI) including peak fields, shunt impedance and the modified Poynting vector. Visualizing these results becomes increasingly more difficult as the number of objectives increases, therefore, in order to understand these frontiers, we provide several techniques for analyzing, visualizing and using multi-dimensional Pareto fronts specifically for RF cavity design.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB355

About •

paper received ※ 19 May 2021 paper accepted ※ 15 July 2021 issue date ※ 30 August 2021

Export •

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

MOPAB371

A Coupon Tester for Normal Conducting High-Gradient Materials

cavity, coupling, vacuum, klystron

1147

J.W. Lewellen, D. Gorelov, D. Perez, E.I. Simakov
LANL, Los Alamos, New Mexico, USA
M.E. Schneider
Michigan State University, East Lansing, Michigan, USA

Funding: Los Alamos National Laboratory LDRD Program
A coupon tester is an RF structure used to subject a material sample to very high RF fields, with the fields on the sample, or coupon, being higher than elsewhere in the cavity. To date, most such cavities were originally intended to explore the RF properties of superconducting materials, and can expose the sample to strong magnetic fields, but weak to no electric fields. As part of a program to develop materials and structures for high-gradient (> 100 MV/m), low-breakdown-rate normal-conducting accelerators, we have designed a C-band (5.712 GHz) cavity intended to subject samples to both magnetic and electric fields comparable to those experienced in high-gradient structure designs, using a TM-mode cavity; the electric and magnetic fields along the sample coupon can be directly compared to the fields on the iris of high-gradient structures. This poster will present the design criteria for our coupon tester cavity, nominal operating parameters, and our structure concept. The cavity design will be refined over the next several months, and will be constructed and in service near the start of 2022.

Poster MOPAB371 [0.764 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB371

About •

paper received ※ 17 May 2021 paper accepted ※ 26 May 2021 issue date ※ 30 August 2021

Export •

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

WEPAB295

Parameter Estimation of Short Pulse Normal-Conducting Standing Wave Cavities

cavity, gun, coupling, resonance

3351

S. Pfeiffer, J. Branlard, F. Burkart, M. Hoffmann, H. Schlarb
DESY, Hamburg, Germany

The linear accelerator ARES (Accelerator Research Experiment at SINBAD) is a new research facility at DESY. Electron bunches with a maximum repetition rate of 50 Hz are accelerated to a target energy of 155 MeV. The facility aims for ultra-stable sub-femtosecond arrival-times and high peak-currents at the experiment, placing high demands on the reference distribution and field regulation of the RF structure. In this contribution, we present the physical parameter estimation of key RF properties such as cavity detuning not directly measurable on the RF field decay. The method can be used as a fast monitor of inner cell temperature. The estimated properties are finally compared with the measured ones.

Poster WEPAB295 [0.860 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB295

About •

paper received ※ 19 May 2021 paper accepted ※ 05 July 2021 issue date ※ 26 August 2021

Export •

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

THPAB223

Energy Compression System Radio Frequency Design at the Canadian Light Source

linac, impedance, GUI, simulation

4231

E.J. Ericson, D. Bertwistle, M.J. Boland
CLS, Saskatoon, Saskatchewan, Canada

The Canadian Light Source (CLS), Canada’s only synchrotron light source, is considering a linear accelerator (LINAC) upgrade. As a result, the radio frequency (RF) structure in the downstream Energy Compression System (ECS) needs to be redesigned. In this paper, we describe the design process followed to determine the geometry of the RF structure cells and coupler.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB223

About •

paper received ※ 18 May 2021 paper accepted ※ 28 July 2021 issue date ※ 28 August 2021

Export •

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