NAPAC2016 - List of Authors (Burov, A.V.)

Paper	Title	Page
WEPOA14	Resistive Wall Growth Rate Measurements in the Fermilab Recycler	719
	R. Ainsworth, P. Adamson, A.V. Burov, I. Kourbanis Fermilab, Batavia, Illinois, USA
	Impedance could represent a limitation of running high intensity beams in the Fermilab recycler. With high intensity upgrades foreseen, it is important to quantify the impedance. To do this, studies have been performed measuring the growth rate of presumably the resistive wall instability. The growth rates at varying intensities and chromaticities are shown. The measured growth rates are compared to ones calculated with the resistive wall impedance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA14
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEA3CO03	Efficiency of Feedbacks for Suppression of Transverse Instabilities of Bunched Beams
	A.V. Burov Fermilab, Batavia, Illinois, USA
	Which gain and phase have to be set for a bunch-by-bunch transverse damper, and at which chromaticity it is better to stay? How high are the remaining growth rates for the given gain and beam parameters? These questions are addressed by means of two Vlasov solvers: for high energy beams, the Nested Head Tail solver is used, while for strong space charge case, a new SChargeV code is exploited.
	Slides WEA3CO03 [6.007 MB]
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEA4CO03	Intrinsic Landau Damping of Space Charge Modes at Coupling Resonance	863
	A. Macridin, J.F. Amundson, A.V. Burov, P. Spentzouris, E.G. Stern Fermilab, Batavia, Illinois, USA
	Funding: This work was performed at Fermilab, operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy. Using Synergia accelerator modeling package and Dynamic Mode Decomposition technique, the properties of the first transverse dipole mode in Gaussian bunches with space charge are compared at transverse coupling resonance and off-resonance. The Landau damping at coupling resonance and in the strong space charge regime is a factor of two larger, while the mode's tune and shape are nearly the same. While the damping mechanism in the off-resonance case fits well with the classical Landau damping paradigm, the enhancement at coupling resonance is due to a higher order mode-particle coupling term which is modulated by the amplitude oscillation of the resonance trapped particles.
	Slides WEA4CO03 [3.422 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEA4CO03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOA30	SCHARGEV 1.0 - Strong Space Charge Vlasov Solver	1164
	T. Zolkin, A.V. Burov Fermilab, Batavia, Illinois, USA
	The space charge (SC) is known to be one of the major limitations for the collective transverse beam stability. When space charge is strong, i.e. SC tune shift much greater than synchrotron tune, the problem allows an exact analytical solution. For that practically important case we present a fast and effective Vlasov solver SCHARGEV (Space CHARGE Vlasov) which calculates a complete eigensystem (spatial shapes of modes and frequency spectra) and therefore provides the growth rates and the thresholds of instabilities. SCHARGEV 1.0 includes driving and detuning wake forces, and, any feedback system (damper). In the next version we will include coupled bunch interaction and Landau damping. Numerical examples for FermiLab Recycler and CERN SPS are presented.
	Poster THPOA30 [1.493 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA30
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOA48	Model of Electron Cloud Instability in Fermilab Recycler	1197
	S. A. Antipov University of Chicago, Chicago, Illinois, USA A.V. Burov, S. Nagaitsev Fermilab, Batavia, Illinois, USA
	An electron cloud instability might limit the intensity in the Fermilab Recycler after the PIP-II upgrade. A multibunch instability typically develops in the horizontal plane within a hundred turns and, in certain conditions, leads to beam loss. Recent studies have indicated that the instability is caused by an electron cloud, trapped in the Recycler index dipole magnets. We developed an analytical model of an electron cloud driven instability with the electrons trapped in combined function dipoles. The resulting instability growth rate of about 30 revolutions is consistent with experimental observations and qualitatively agrees with the simulation in the PEI code. The model allows an estimation of the instability rate for the future in-tensity upgrades.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA48
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Resistive Wall Growth Rate Measurements in the Fermilab Recycler

719

R. Ainsworth, P. Adamson, A.V. Burov, I. Kourbanis
Fermilab, Batavia, Illinois, USA

Impedance could represent a limitation of running high intensity beams in the Fermilab recycler. With high intensity upgrades foreseen, it is important to quantify the impedance. To do this, studies have been performed measuring the growth rate of presumably the resistive wall instability. The growth rates at varying intensities and chromaticities are shown. The measured growth rates are compared to ones calculated with the resistive wall impedance.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA14

Export •

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

WEA3CO03

Efficiency of Feedbacks for Suppression of Transverse Instabilities of Bunched Beams

A.V. Burov
Fermilab, Batavia, Illinois, USA

Which gain and phase have to be set for a bunch-by-bunch transverse damper, and at which chromaticity it is better to stay? How high are the remaining growth rates for the given gain and beam parameters? These questions are addressed by means of two Vlasov solvers: for high energy beams, the Nested Head Tail solver is used, while for strong space charge case, a new SChargeV code is exploited.

Slides WEA3CO03 [6.007 MB]

Export •

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

WEA4CO03

Intrinsic Landau Damping of Space Charge Modes at Coupling Resonance

863

A. Macridin, J.F. Amundson, A.V. Burov, P. Spentzouris, E.G. Stern
Fermilab, Batavia, Illinois, USA

Funding: This work was performed at Fermilab, operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Using Synergia accelerator modeling package and Dynamic Mode Decomposition technique, the properties of the first transverse dipole mode in Gaussian bunches with space charge are compared at transverse coupling resonance and off-resonance. The Landau damping at coupling resonance and in the strong space charge regime is a factor of two larger, while the mode's tune and shape are nearly the same. While the damping mechanism in the off-resonance case fits well with the classical Landau damping paradigm, the enhancement at coupling resonance is due to a higher order mode-particle coupling term which is modulated by the amplitude oscillation of the resonance trapped particles.

Slides WEA4CO03 [3.422 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEA4CO03

Export •

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

THPOA30

SCHARGEV 1.0 - Strong Space Charge Vlasov Solver

1164

T. Zolkin, A.V. Burov
Fermilab, Batavia, Illinois, USA

The space charge (SC) is known to be one of the major limitations for the collective transverse beam stability. When space charge is strong, i.e. SC tune shift much greater than synchrotron tune, the problem allows an exact analytical solution. For that practically important case we present a fast and effective Vlasov solver SCHARGEV (Space CHARGE Vlasov) which calculates a complete eigensystem (spatial shapes of modes and frequency spectra) and therefore provides the growth rates and the thresholds of instabilities. SCHARGEV 1.0 includes driving and detuning wake forces, and, any feedback system (damper). In the next version we will include coupled bunch interaction and Landau damping. Numerical examples for FermiLab Recycler and CERN SPS are presented.

Poster THPOA30 [1.493 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA30

Export •

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

THPOA48

Model of Electron Cloud Instability in Fermilab Recycler

1197

S. A. Antipov
University of Chicago, Chicago, Illinois, USA
A.V. Burov, S. Nagaitsev
Fermilab, Batavia, Illinois, USA

An electron cloud instability might limit the intensity in the Fermilab Recycler after the PIP-II upgrade. A multibunch instability typically develops in the horizontal plane within a hundred turns and, in certain conditions, leads to beam loss. Recent studies have indicated that the instability is caused by an electron cloud, trapped in the Recycler index dipole magnets. We developed an analytical model of an electron cloud driven instability with the electrons trapped in combined function dipoles. The resulting instability growth rate of about 30 revolutions is consistent with experimental observations and qualitatively agrees with the simulation in the PEI code. The model allows an estimation of the instability rate for the future in-tensity upgrades.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA48

Export •

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