NAPAC2022 - List of Keywords (kicker)

Paper	Title	Other Keywords	Page
MOPA33	Waker Experiments at Fermilab Recycler Ring	experiment, space-charge, feedback, impedance	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)

TUPA17	Beam-Based Alignment of Sextupole Families in the EIC	sextupole, alignment, lattice, closed-orbit	378
	J.C. Wang, G.H. Hoffstaetter, D. Sagan Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA C. Montag BNL, Upton, New York, USA
	To steer the closed orbit in a storage ring through the center of its quadrupoles, it is important to accurately know the quadrupole centers relative to nearby beam position monitors. Usually this is achieved by beam-based alignment (BBA). Assuming the quadrupole strength can be changed individually, one finds the BPM reading where changing a quadrupole’s strength does not alter the closed orbit. Since most quadrupoles are powered in series, they can only be varied independently if costly power supplies are added. For the EIC electron storage ring (ESR), we investigate whether sextupole BBA can be used instead. Individually powered sextupole BBA techniques already exist, but most sextupoles are powered in families and cannot be individually changed. We therefore developed a method where a localized bump changes the beam excursion in a single sextupole of a family, turning off all families that also have sextupoles in the bump. The bump amplitude at which the sextupole does not cause a closed orbit kick determines the sextupole’s alignment. This study was made to investigate the precision to which this method can be utilized.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA17
About •	Received ※ 04 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 29 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEZD6	Manufacturing the Harmonic Kicker Cavity Prototype for the Electron-Ion Collider	cavity, electron, collider, MMI	601
	S.A. Overstreet, M.W. Bruker, G.A. Grose, J. Guo, J. Henry, G.-T. Park, R.A. Rimmer, H. Wang, R.S. Williams JLab, Newport News, Virginia, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177 High-bunch-frequency beam-separation schemes, such as the injection scheme proposed for the Rapid Cycling Synchrotron at the Electron-Ion Collider, demand rise and fall times an order of magnitude below what can realistically be accomplished with a stripline kicker. Nanosecond-time-scale kick waveforms can instead be obtained by Fourier synthesis in a harmonically resonant quarter-wave radio-frequency cavity which is optimized for high shunt impedance. Originally developed for the Jefferson Lab Electron-Ion Collider (JLEIC) Circulator Cooler Ring, a hypothetical 11-pass ring driven by an energy-recovery linac at Jefferson Lab, our high-power prototype of such a harmonic kicker cavity, which operates at five modes at the same time, will demonstrate the viability of this concept with a beam test at Jefferson Lab. As the geometry of the cavity, tight mechanical tolerances, and number of ports complicate the design and manufacturing process, special care must be given to the order of the manufacturing steps. We present our experiences with the manufacturability of the present design, lessons learned, and first RF test results from the prototype.
	Slides WEZD6 [12.312 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEZD6
About •	Received ※ 04 August 2022 — Revised ※ 05 August 2022 — Accepted ※ 18 August 2022 — Issue date ※ 31 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA50	Initial Development of a High-Voltage Pulse Generator for a Short-Pulse Kicker	flattop, collider, high-voltage, operation	745
	J. Prager, K.E. Miller, K. Muggli, C. Schmidt, H. Yeager EHT, Seattle, Washington, USA
	Funding: This work was funded by a DOE SBIR (DE-SC0021470). The future Electron Ion Collider, to be located at Brookhaven National Laboratory (BNL), will require a new short-pulse stripline kicker for the 150 MeV energy recovery LINAC. The pulse generator must produce ±50 kV pulses with widths less than 38 ns into a 50° kicker load and with low jitter. The power system must be highly reliable and robust to potential faults. Eagle Harbor Technologies (EHT), Inc. is leveraging our previous experience developing inductive adders to produce a high-voltage pulse generator that can meet the needs of the BNL kickers. In this program, EHT designed a single inductive adder stage and demonstrated the challenging pulse characteristics including fast rise and fall times, low jitter, and flattop stability while operating at the full current (1 kA). EHT will present the development status and output waveforms.
	Poster WEPA50 [1.118 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA50
About •	Received ※ 01 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 12 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPA67	Effects of Transverse Dependence of Kicks in Simulations of Microbunched Electron Cooling	hadron, electron, simulation, proton	780
	W.F. Bergan BNL, Upton, New York, USA G. Stupakov SLAC, Menlo Park, California, USA
	Funding: This work was supported by Brookhaven Science Associates, LLC under contract No. DE-SC0012704 with the U.S. Department of Energy, and by the Department of Energy, contract DE-AC03-76SF00515. Microbunched electron cooling (MBEC) is a cooling scheme in which a beam of hadrons to be cooled induces energy perturbations in a beam of electrons. These electron energy perturbations are amplified and turned into density modulations, which in turn provide energy kicks to the hadrons, tending to cool them. For simplification, previous work has modelled the electron-hadron interactions using a disc-disc model, assuming that the inter-particle kicks depend only on the longitudinal distances between individual hadrons and electrons. In reality, these kicks will also have a transverse dependence, which will impact the cooling process. We incorporate this transverse kick dependence into our simulations of the cooling process, allowing us to better understand the physics and provide improved design goals for the MBEC cooler for the Electron-Ion Collider.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA67
About •	Received ※ 19 July 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 26 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	impedance, 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)

WEPA85	Localized Beam Induced Heating Analysis of the EIC Vacuum Chamber Components	vacuum, electron, simulation, injection	833
	M.P. Sangroula, D.M. Gassner, C.J. Liaw, C. Liu, P. Thieberger BNL, Upton, New York, USA J.R. Bellon, A. Blednykh, C. Hetzel, S. Verdú-Andrés Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy The Electron-Ion Collider (EIC), to be built at Brookhaven National Laboratory (BNL), is designed to provide a high electron-proton luminosity of 10³⁴ cm^-2 s^-1. One of the challenging tasks for the Electron Storage Ring (ESR) is to operate at an average beam current of 2.5 A within 1160 bunches with a ~ 7 mm bunch length. The Hadron Storage Ring (HSR) will accumulate an average current of 0.69 A within 290 bunches with a 60 mm bunch length. Both rings require the impedance budget simulations. The intense e-beam in the ESR can lead to the overheating of vacuum chamber components due to localized metallic losses. This paper focuses on the beam-induced heating analysis of the ESR vacuum components including bellows, gate-valve, and BPM. To perform thermal analysis, the resistive loss on individual components is calculated with CST and then fed to ANSYS to determine the temperature distribution on the vacuum components. Preliminary results suggest that active water cooling will be required for most of the ESR vacuum components. Similar approach is applied to the HSR vacuum components. The thermal analysis of the HSR stripline injection kicker is presented.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA85
About •	Received ※ 03 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 10 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPA33

Waker Experiments at Fermilab Recycler Ring

experiment, space-charge, feedback, impedance

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)

TUPA17

Beam-Based Alignment of Sextupole Families in the EIC

sextupole, alignment, lattice, closed-orbit

378

J.C. Wang, G.H. Hoffstaetter, D. Sagan
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
C. Montag
BNL, Upton, New York, USA

To steer the closed orbit in a storage ring through the center of its quadrupoles, it is important to accurately know the quadrupole centers relative to nearby beam position monitors. Usually this is achieved by beam-based alignment (BBA). Assuming the quadrupole strength can be changed individually, one finds the BPM reading where changing a quadrupole’s strength does not alter the closed orbit. Since most quadrupoles are powered in series, they can only be varied independently if costly power supplies are added. For the EIC electron storage ring (ESR), we investigate whether sextupole BBA can be used instead. Individually powered sextupole BBA techniques already exist, but most sextupoles are powered in families and cannot be individually changed. We therefore developed a method where a localized bump changes the beam excursion in a single sextupole of a family, turning off all families that also have sextupoles in the bump. The bump amplitude at which the sextupole does not cause a closed orbit kick determines the sextupole’s alignment. This study was made to investigate the precision to which this method can be utilized.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA17

About •

Received ※ 04 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 29 August 2022

Cite •

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

WEZD6

Manufacturing the Harmonic Kicker Cavity Prototype for the Electron-Ion Collider

cavity, electron, collider, MMI

601

S.A. Overstreet, M.W. Bruker, G.A. Grose, J. Guo, J. Henry, G.-T. Park, R.A. Rimmer, H. Wang, R.S. Williams
JLab, Newport News, Virginia, USA

Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177
High-bunch-frequency beam-separation schemes, such as the injection scheme proposed for the Rapid Cycling Synchrotron at the Electron-Ion Collider, demand rise and fall times an order of magnitude below what can realistically be accomplished with a stripline kicker. Nanosecond-time-scale kick waveforms can instead be obtained by Fourier synthesis in a harmonically resonant quarter-wave radio-frequency cavity which is optimized for high shunt impedance. Originally developed for the Jefferson Lab Electron-Ion Collider (JLEIC) Circulator Cooler Ring, a hypothetical 11-pass ring driven by an energy-recovery linac at Jefferson Lab, our high-power prototype of such a harmonic kicker cavity, which operates at five modes at the same time, will demonstrate the viability of this concept with a beam test at Jefferson Lab. As the geometry of the cavity, tight mechanical tolerances, and number of ports complicate the design and manufacturing process, special care must be given to the order of the manufacturing steps. We present our experiences with the manufacturability of the present design, lessons learned, and first RF test results from the prototype.

Slides WEZD6 [12.312 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEZD6

About •

Received ※ 04 August 2022 — Revised ※ 05 August 2022 — Accepted ※ 18 August 2022 — Issue date ※ 31 August 2022

Cite •

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

WEPA50

Initial Development of a High-Voltage Pulse Generator for a Short-Pulse Kicker

flattop, collider, high-voltage, operation

745

J. Prager, K.E. Miller, K. Muggli, C. Schmidt, H. Yeager
EHT, Seattle, Washington, USA

Funding: This work was funded by a DOE SBIR (DE-SC0021470).
The future Electron Ion Collider, to be located at Brookhaven National Laboratory (BNL), will require a new short-pulse stripline kicker for the 150 MeV energy recovery LINAC. The pulse generator must produce ±50 kV pulses with widths less than 38 ns into a 50° kicker load and with low jitter. The power system must be highly reliable and robust to potential faults. Eagle Harbor Technologies (EHT), Inc. is leveraging our previous experience developing inductive adders to produce a high-voltage pulse generator that can meet the needs of the BNL kickers. In this program, EHT designed a single inductive adder stage and demonstrated the challenging pulse characteristics including fast rise and fall times, low jitter, and flattop stability while operating at the full current (1 kA). EHT will present the development status and output waveforms.

Poster WEPA50 [1.118 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA50

About •

Received ※ 01 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 12 August 2022

Cite •

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

WEPA67

Effects of Transverse Dependence of Kicks in Simulations of Microbunched Electron Cooling

hadron, electron, simulation, proton

780

W.F. Bergan
BNL, Upton, New York, USA
G. Stupakov
SLAC, Menlo Park, California, USA

Funding: This work was supported by Brookhaven Science Associates, LLC under contract No. DE-SC0012704 with the U.S. Department of Energy, and by the Department of Energy, contract DE-AC03-76SF00515.
Microbunched electron cooling (MBEC) is a cooling scheme in which a beam of hadrons to be cooled induces energy perturbations in a beam of electrons. These electron energy perturbations are amplified and turned into density modulations, which in turn provide energy kicks to the hadrons, tending to cool them. For simplification, previous work has modelled the electron-hadron interactions using a disc-disc model, assuming that the inter-particle kicks depend only on the longitudinal distances between individual hadrons and electrons. In reality, these kicks will also have a transverse dependence, which will impact the cooling process. We incorporate this transverse kick dependence into our simulations of the cooling process, allowing us to better understand the physics and provide improved design goals for the MBEC cooler for the Electron-Ion Collider.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA67

About •

Received ※ 19 July 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 26 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

impedance, 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)

WEPA85

Localized Beam Induced Heating Analysis of the EIC Vacuum Chamber Components

vacuum, electron, simulation, injection

833

M.P. Sangroula, D.M. Gassner, C.J. Liaw, C. Liu, P. Thieberger
BNL, Upton, New York, USA
J.R. Bellon, A. Blednykh, C. Hetzel, S. Verdú-Andrés
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy
The Electron-Ion Collider (EIC), to be built at Brookhaven National Laboratory (BNL), is designed to provide a high electron-proton luminosity of 10³⁴ cm^-2 s^-1. One of the challenging tasks for the Electron Storage Ring (ESR) is to operate at an average beam current of 2.5 A within 1160 bunches with a ~ 7 mm bunch length. The Hadron Storage Ring (HSR) will accumulate an average current of 0.69 A within 290 bunches with a 60 mm bunch length. Both rings require the impedance budget simulations. The intense e-beam in the ESR can lead to the overheating of vacuum chamber components due to localized metallic losses. This paper focuses on the beam-induced heating analysis of the ESR vacuum components including bellows, gate-valve, and BPM. To perform thermal analysis, the resistive loss on individual components is calculated with CST and then fed to ANSYS to determine the temperature distribution on the vacuum components. Preliminary results suggest that active water cooling will be required for most of the ESR vacuum components. Similar approach is applied to the HSR vacuum components. The thermal analysis of the HSR stripline injection kicker is presented.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEPA85

About •

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

Cite •

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