NAPAC2022 - List of Keywords (impedance)

Paper	Title	Other Keywords	Page
MOZE4	Ceramic Enhanced Accelerator Structure Low Power Test and Designs of High Power and Beam Tests	cavity, electron, accelerating-gradient, simulation	49
	H. Xu, M.R. Bradley, L.D. Duffy, M.A. Holloway, J. Upadhyay LANL, Los Alamos, New Mexico, USA
	Funding: Research was supported by the Laboratory Directed Research and Development program of Los Alamos National Laboratory, under project number 20210083ER. A ceramic enhanced accelerator structure (CEAS) uses a concentric ceramic ring placed inside a metallic pillbox cavity to significantly increase the shunt impedance of the cavity. Single cell standing wave CEAS cavities are designed, built, and tested at low power at 5.1 GHz. The results indicate 40% increase in shunt impedance compared to that of a purely metallic pillbox cavity. A beam test setup has been designed to use a single cell CEAS cavity to modulate a 30-keV direct-current (DC) electron beam at an accelerating gradient of 1 to 2 MV/m to verify the beam acceleration capability of the CEAS concept and to study the potential charging effect on the ceramic component during the operation. Another single cell standing wave CEAS cavity has been designed for high power test at 5.7 GHz for the high accelerating gradient capability.
	Slides MOZE4 [1.652 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZE4
About •	Received ※ 01 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 07 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOZE5	Simulation and Experimental Results of Dielectric Disk Accelerating Structures	accelerating-gradient, experiment, wakefield, simulation	52
	S. Weatherly, E.E. Wisniewski Illinois Institute of Technology, Chicago, Illinois, USA D.S. Doran, C.-J. Jing, J.F. Power, E.E. Wisniewski ANL, Lemont, Illinois, USA B.T. Freemire, C.-J. Jing Euclid Beamlabs, Bolingbrook, USA
	Funding: Contract DE-SC0019864 to Euclid Beamlabs LLC. AWA work from U.S. DOE Office of Science under Contract DE-AC02-06CH11357. Chicagoland Accelerator Science Traineeship U.S. DOE award number DE-SC-0020379 A method of decreasing the required footprint of linear accelerators and improving their energy efficiency is to employ Dielectric Disk Accelerators (DDAs) with short RF pulses ( ∼ 9 ns). A DDA is an accelerating structure that utilizes dielectric disks to improve the shunt impedance. Two DDA structures have been designed and tested at the Argonne Wakefield Accelerator. A single cell clamped DDA structure recently achieved an accelerating gradient of 1{02} MV/m. A multi-cell clamped DDA structure has been designed and is being fabricated. Simulation results for this new structure show a 1{08} MV/m accelerating gradient with 400 MW of input power with a high shunt impedance and group velocity. The engineering design has been improved from the single cell structure to ensure consistent clamping over the entire structure.
	Slides MOZE5 [9.338 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZE5
About •	Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 21 August 2022 — Issue date ※ 06 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA33	Waker Experiments at Fermilab Recycler Ring	experiment, space-charge, feedback, kicker	124
	O. Mohsen, R. Ainsworth, N. Eddy Fermilab, Batavia, Illinois, USA
	Attaining high-intensity hadron beams is often limited due to the transverse collective instabilities, whose understanding is thus required to see and possibly extend the intensity limitations. To explore such instabilities, a novel artificial wake system, the waker, has been built and tested at the Fermilab Recycler Ring (RR). In this report, we show recent upgrades of the waker. Also, we present experimental studies of instabilities at various space charge and wake parameters.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA33
About •	Received ※ 03 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 28 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPA46	Cryogenic Dielectric Structure with GΩ/m Level Shunt Impedance	cryogenics, simulation, acceleration, accelerating-gradient	157
	R.A. Kostin, C. Jing Euclid Beamlabs, Bolingbrook, USA
	Shunt impedance is one of the most important parameters characterizing particle acceleration efficiency. It is known that RF losses are reduced at cryogenic temperatures. For example, a record high shunt impedance of 350 MΩ/m was demonstrated recently for all metal X-band accelerating structure, which is more than 2 times higher than that at room temperature. In this article we present a novel hybrid dielectric structure which can achieve even higher shunt impedance due to the fact that losses in dielectric materials reduced much more than in pure copper.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA46
About •	Received ※ 12 August 2022 — Revised ※ 16 August 2022 — Accepted ※ 23 August 2022 — Issue date ※ 17 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA56	Beam Coupling Impedances of Asymmetric Components of the Scorpius Induction Linac	resonance, linac, dipole, vacuum	469
	S.S. Kurennoy LANL, Los Alamos, New Mexico, USA
	The transverse beam coupling impedance of induction linacs must be minimized to avoid beam breakdown instability. The vacuum chamber of the Scorpius linac contains complicated asymmetric elements. We present calculations of the transverse impedance for three asymmetric discontinuities: (1) a pumping section between accelerating cells, which contains vacuum plenum, pumping grid, and bellows; (2) a fast flapper valve; and (3) a debris blocker at the end of the linac. The dipole transverse impedance is calculated with CST Studio using both wakefield solver and eigen solver.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA56
About •	Received ※ 01 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 06 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA64	Analysis of Resonant Converter Topology for High-Voltage Modulators	resonance, high-voltage, operation, klystron	486
	M. Sanchez Barrueta, J.T.M. Lyles, M.D.M. Morris LANL, Los Alamos, New Mexico, USA
	Funding: Work Supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396 At the Los Alamos Neutron Science Center (LANSCE), we are considering various topologies to replace obsolete charging supplies and capacitor banks that provide high-voltage direct-current (DC) power to the 44, 805-MHz klystron modulators that drive the LANSCE Coupled Cavity Linac (CCL). Among the possible replacement topologies is the High Voltage Converter Modulator (HVCM), originally designed at LANSCE for use at the Spallation Neutron Source (SNS), to be used as a pulsed high-voltage power supply for klystron-based RF transmitters. The HVCM topology uses high frequency transformers with resonant LC networks for efficient energy conversion and a frequency dependent gain, which permits the use of frequency modulation as a control variable to afford pulse flattening and excellent regulation as demonstrated at SNS. A mathematical analysis is presented that links the converter resonant tank components to the frequency dependent output behavior of the converter modulator. LA-UR-22-25179
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA64
About •	Received ※ 03 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 22 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA26	197 MHz Waveguide Loaded Crabbing Cavity Design for the Electron-Ion Collider	cavity, HOM, GUI, electron	679
	S.U. De Silva, J.R. Delayen ODU, Norfolk, Virginia, USA J. Guo, R.A. Rimmer JLab, Newport News, Virginia, USA Z. Li SLAC, Menlo Park, California, USA B.P. Xiao BNL, Upton, New York, USA
	The Electron-Ion Collider will require crabbing systems at both hadron and electron storage rings in order to reach the desired luminosity goal. The 197 MHz crab cavity system is one of the critical rf systems of the col-lider. The crab cavity, based on the rf-dipole design, ex-plores the option of waveguide load damping to suppress the higher order modes and meet the tight impedance specifications. The cavity is designed with compact dog-bone waveguides with transitions to rectangular wave-guides and waveguide loads. This paper presents the compact 197 MHz crab cavity design with waveguide damping and other ancillaries.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA26
About •	Received ※ 08 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 06 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA53	An Open Radiofrequency Accelerating Structure	coupling, gun, GUI, SRF	753
	S.V. Kuzikov Euclid TechLabs, Solon, Ohio, USA
	We report an open multi-cell accelerating structure. Being integrated with a set of open-end waveguides, this structure can suppress high-order modes (HOMs). All the accelerating cells are connected at the side to rectangular cross-section waveguides which strongly coupled with free space or absorbers. Due to the anti-phased contribution of the cell pairs, the operating mode does not leak out, and has as high-quality factor as for a closed accelerating structure. However, the compensation does not occur for spurious high-order modes. This operating principle also allows for strong coupling between the cells of the structure, which is why high homogeneity of the accelerating fields can be provided along the structure. We discuss the obtained simulation results and possible applications. Its include a normal conducting high-shunt impedance accelerator, a tunable photoinjector’s RF gun, and a high-current, high-selective SRF accelerators.
	Poster WEPA53 [1.817 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA53
About •	Received ※ 01 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 16 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA72	Analysis of Beam-Induced Heating of the NSLS-II Ceramic Vacuum Chambers	kicker, simulation, vacuum, injection	799
	G. Bassi, C. Hetzel, A. Khan, B.N. Kosciuk, M. Seegitz, V.V. Smaluk, R.J. Todd BNL, Upton, New York, USA A. Blednykh Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
	We discuss impedance calculations and related heating issues of the titanium-coated NSLS-II kicker ceramic chambers, with the titanium coating thickness estimated from in situ measurements of the end-to-end resistance of each chamber. Power densities are calculated on the titanium coating to allow for thermal analysis with the code ANSYS and comparison with heating measurements. The impedance analysis is performed using a realistic model of the ceramic complex permittivity, and special consideration is given to the impedance calculation in the limit of zero titanium coating thickness.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA72
About •	Received ※ 03 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 26 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA73	Numerical Studies of Geometric Impedance at NSLS-II with GdfidL and ECHO3D	simulation, vacuum, wakefield, radiation	802
	A. Khan, M. Seegitz, V.V. Smaluk, R.J. Todd BNL, Upton, New York, USA A. Blednykh Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
	The beam intensity in future low-emittance light sources with small gap wigglers and undulators is limited by the effects of short-range wakefields, especially by the beam-induced heating of the vacuum chamber components. We have cross-checked two electromagnetic solvers, GdfidL and ECHO3D, by simulation of the short-range wakefields in the NSLS-II flange absorber and in the taper transition of an in-vacuum undulator to test the consistency and precision of the wakefield models.
	Poster WEPA73 [1.057 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA73
About •	Received ※ 01 August 2022 — Revised ※ 03 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 01 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOZE4

Ceramic Enhanced Accelerator Structure Low Power Test and Designs of High Power and Beam Tests

cavity, electron, accelerating-gradient, simulation

49

H. Xu, M.R. Bradley, L.D. Duffy, M.A. Holloway, J. Upadhyay
LANL, Los Alamos, New Mexico, USA

Funding: Research was supported by the Laboratory Directed Research and Development program of Los Alamos National Laboratory, under project number 20210083ER.
A ceramic enhanced accelerator structure (CEAS) uses a concentric ceramic ring placed inside a metallic pillbox cavity to significantly increase the shunt impedance of the cavity. Single cell standing wave CEAS cavities are designed, built, and tested at low power at 5.1 GHz. The results indicate 40% increase in shunt impedance compared to that of a purely metallic pillbox cavity. A beam test setup has been designed to use a single cell CEAS cavity to modulate a 30-keV direct-current (DC) electron beam at an accelerating gradient of 1 to 2 MV/m to verify the beam acceleration capability of the CEAS concept and to study the potential charging effect on the ceramic component during the operation. Another single cell standing wave CEAS cavity has been designed for high power test at 5.7 GHz for the high accelerating gradient capability.

Slides MOZE4 [1.652 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZE4

About •

Received ※ 01 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 07 October 2022

Cite •

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

MOZE5

Simulation and Experimental Results of Dielectric Disk Accelerating Structures

accelerating-gradient, experiment, wakefield, simulation

52

S. Weatherly, E.E. Wisniewski
Illinois Institute of Technology, Chicago, Illinois, USA
D.S. Doran, C.-J. Jing, J.F. Power, E.E. Wisniewski
ANL, Lemont, Illinois, USA
B.T. Freemire, C.-J. Jing
Euclid Beamlabs, Bolingbrook, USA

Funding: Contract DE-SC0019864 to Euclid Beamlabs LLC. AWA work from U.S. DOE Office of Science under Contract DE-AC02-06CH11357. Chicagoland Accelerator Science Traineeship U.S. DOE award number DE-SC-0020379
A method of decreasing the required footprint of linear accelerators and improving their energy efficiency is to employ Dielectric Disk Accelerators (DDAs) with short RF pulses ( ∼ 9 ns). A DDA is an accelerating structure that utilizes dielectric disks to improve the shunt impedance. Two DDA structures have been designed and tested at the Argonne Wakefield Accelerator. A single cell clamped DDA structure recently achieved an accelerating gradient of 1{02} MV/m. A multi-cell clamped DDA structure has been designed and is being fabricated. Simulation results for this new structure show a 1{08} MV/m accelerating gradient with 400 MW of input power with a high shunt impedance and group velocity. The engineering design has been improved from the single cell structure to ensure consistent clamping over the entire structure.

Slides MOZE5 [9.338 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOZE5

About •

Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 21 August 2022 — Issue date ※ 06 October 2022

Cite •

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

MOPA33

Waker Experiments at Fermilab Recycler Ring

experiment, space-charge, feedback, kicker

124

O. Mohsen, R. Ainsworth, N. Eddy
Fermilab, Batavia, Illinois, USA

Attaining high-intensity hadron beams is often limited due to the transverse collective instabilities, whose understanding is thus required to see and possibly extend the intensity limitations. To explore such instabilities, a novel artificial wake system, the waker, has been built and tested at the Fermilab Recycler Ring (RR). In this report, we show recent upgrades of the waker. Also, we present experimental studies of instabilities at various space charge and wake parameters.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA33

About •

Received ※ 03 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 28 August 2022

Cite •

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

MOPA46

Cryogenic Dielectric Structure with GΩ/m Level Shunt Impedance

cryogenics, simulation, acceleration, accelerating-gradient

157

R.A. Kostin, C. Jing
Euclid Beamlabs, Bolingbrook, USA

Shunt impedance is one of the most important parameters characterizing particle acceleration efficiency. It is known that RF losses are reduced at cryogenic temperatures. For example, a record high shunt impedance of 350 MΩ/m was demonstrated recently for all metal X-band accelerating structure, which is more than 2 times higher than that at room temperature. In this article we present a novel hybrid dielectric structure which can achieve even higher shunt impedance due to the fact that losses in dielectric materials reduced much more than in pure copper.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA46

About •

Received ※ 12 August 2022 — Revised ※ 16 August 2022 — Accepted ※ 23 August 2022 — Issue date ※ 17 September 2022

Cite •

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

TUPA56

Beam Coupling Impedances of Asymmetric Components of the Scorpius Induction Linac

resonance, linac, dipole, vacuum

469

S.S. Kurennoy
LANL, Los Alamos, New Mexico, USA

The transverse beam coupling impedance of induction linacs must be minimized to avoid beam breakdown instability. The vacuum chamber of the Scorpius linac contains complicated asymmetric elements. We present calculations of the transverse impedance for three asymmetric discontinuities: (1) a pumping section between accelerating cells, which contains vacuum plenum, pumping grid, and bellows; (2) a fast flapper valve; and (3) a debris blocker at the end of the linac. The dipole transverse impedance is calculated with CST Studio using both wakefield solver and eigen solver.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA56

About •

Received ※ 01 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 06 October 2022

Cite •

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

TUPA64

Analysis of Resonant Converter Topology for High-Voltage Modulators

resonance, high-voltage, operation, klystron

486

M. Sanchez Barrueta, J.T.M. Lyles, M.D.M. Morris
LANL, Los Alamos, New Mexico, USA

Funding: Work Supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
At the Los Alamos Neutron Science Center (LANSCE), we are considering various topologies to replace obsolete charging supplies and capacitor banks that provide high-voltage direct-current (DC) power to the 44, 805-MHz klystron modulators that drive the LANSCE Coupled Cavity Linac (CCL). Among the possible replacement topologies is the High Voltage Converter Modulator (HVCM), originally designed at LANSCE for use at the Spallation Neutron Source (SNS), to be used as a pulsed high-voltage power supply for klystron-based RF transmitters. The HVCM topology uses high frequency transformers with resonant LC networks for efficient energy conversion and a frequency dependent gain, which permits the use of frequency modulation as a control variable to afford pulse flattening and excellent regulation as demonstrated at SNS. A mathematical analysis is presented that links the converter resonant tank components to the frequency dependent output behavior of the converter modulator.
LA-UR-22-25179

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA64

About •

Received ※ 03 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 22 August 2022

Cite •

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

WEPA26

197 MHz Waveguide Loaded Crabbing Cavity Design for the Electron-Ion Collider

cavity, HOM, GUI, electron

679

S.U. De Silva, J.R. Delayen
ODU, Norfolk, Virginia, USA
J. Guo, R.A. Rimmer
JLab, Newport News, Virginia, USA
Z. Li
SLAC, Menlo Park, California, USA
B.P. Xiao
BNL, Upton, New York, USA

The Electron-Ion Collider will require crabbing systems at both hadron and electron storage rings in order to reach the desired luminosity goal. The 197 MHz crab cavity system is one of the critical rf systems of the col-lider. The crab cavity, based on the rf-dipole design, ex-plores the option of waveguide load damping to suppress the higher order modes and meet the tight impedance specifications. The cavity is designed with compact dog-bone waveguides with transitions to rectangular wave-guides and waveguide loads. This paper presents the compact 197 MHz crab cavity design with waveguide damping and other ancillaries.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA26

About •

Received ※ 08 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 06 September 2022

Cite •

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

WEPA53

An Open Radiofrequency Accelerating Structure

coupling, gun, GUI, SRF

753

S.V. Kuzikov
Euclid TechLabs, Solon, Ohio, USA

We report an open multi-cell accelerating structure. Being integrated with a set of open-end waveguides, this structure can suppress high-order modes (HOMs). All the accelerating cells are connected at the side to rectangular cross-section waveguides which strongly coupled with free space or absorbers. Due to the anti-phased contribution of the cell pairs, the operating mode does not leak out, and has as high-quality factor as for a closed accelerating structure. However, the compensation does not occur for spurious high-order modes. This operating principle also allows for strong coupling between the cells of the structure, which is why high homogeneity of the accelerating fields can be provided along the structure. We discuss the obtained simulation results and possible applications. Its include a normal conducting high-shunt impedance accelerator, a tunable photoinjector’s RF gun, and a high-current, high-selective SRF accelerators.

Poster WEPA53 [1.817 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA53

About •

Received ※ 01 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 16 August 2022

Cite •

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

WEPA72

Analysis of Beam-Induced Heating of the NSLS-II Ceramic Vacuum Chambers

kicker, simulation, vacuum, injection

799

G. Bassi, C. Hetzel, A. Khan, B.N. Kosciuk, M. Seegitz, V.V. Smaluk, R.J. Todd
BNL, Upton, New York, USA
A. Blednykh
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA

We discuss impedance calculations and related heating issues of the titanium-coated NSLS-II kicker ceramic chambers, with the titanium coating thickness estimated from in situ measurements of the end-to-end resistance of each chamber. Power densities are calculated on the titanium coating to allow for thermal analysis with the code ANSYS and comparison with heating measurements. The impedance analysis is performed using a realistic model of the ceramic complex permittivity, and special consideration is given to the impedance calculation in the limit of zero titanium coating thickness.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA72

About •

Received ※ 03 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 26 September 2022

Cite •

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

WEPA73

Numerical Studies of Geometric Impedance at NSLS-II with GdfidL and ECHO3D

simulation, vacuum, wakefield, radiation

802

A. Khan, M. Seegitz, V.V. Smaluk, R.J. Todd
BNL, Upton, New York, USA
A. Blednykh
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA

The beam intensity in future low-emittance light sources with small gap wigglers and undulators is limited by the effects of short-range wakefields, especially by the beam-induced heating of the vacuum chamber components. We have cross-checked two electromagnetic solvers, GdfidL and ECHO3D, by simulation of the short-range wakefields in the NSLS-II flange absorber and in the taper transition of an in-vacuum undulator to test the consistency and precision of the wakefield models.

Poster WEPA73 [1.057 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA73

About •

Received ※ 01 August 2022 — Revised ※ 03 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 01 September 2022

Cite •

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