IPAC2014 - List of Authors (Meseck, A.)

Paper	Title	Page
MOPRO106	Status of the HZB ERL Prototype BERLinPro	340
	M. Abo-Bakr, W. Anders, R. Barday, K.B. Bürkmann-Gehrlein, A. Burrill, V. Dürr, A. Jankowiak, C. Kalus, T. Kamps, G. Klemz, J. Knobloch, J. Kolbe, O. Kugeler, B.C. Kuske, A.N. Matveenko, A. Meseck, A. Neumann, K. Ott, E. Panofski, D. Pflückhahn, J. Rahn, J. Rudolph, M. Schmeißer, S.G. Schubert, O. Schüler, J. Völker, S. Wesch HZB, Berlin, Germany
	Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association. The Berlin Energy Recovery Linac Prototype BERLinPro is to be constructed at the Helmholtz Zentrum site in Berlin. The aim of the project is to expand the required accelerator physics and technology knowledge mandatory for the generation of a high current (100 mA), high brilliance (norm. emittance below 1 mm mrad) cw electron beam. Since the funding decision in October 2010 the project has entered a phase of detailed planning. Hardware specifications have been defined and various components have been ordered. Furthermore, extensive tests of principal superconducting accelerator components successfully demonstrated the envisaged hardware performance. A summary of the most recent activities together with the details of the project timeline for the coming years are given in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO106
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TUPRI016	First Studies on Ion Effects in the Accelerator ELSA	1585
	D. Sauerland, W. Hillert, M.T. Switka ELSA, Bonn, Germany A. Markoviḱ, U. van Rienen Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany A. Meseck HZB, Berlin, Germany
	Funding: BMBF (Federal Ministry of Education and Research) In the ELSA stretcher ring electrons are accelerated by a fast energy ramp of 6 GeV/s to a beam energy of 3.2 GeV. The high energetic electrons ionize the residual gas molecules in the beam pipe by collisions or synchrotron radiation. The generated ions in turn accumulate inside the beam potential, causing several undesired effects such as tune shifts and beam instabilities. These effects are studied experimentally at ELSA using its full diagnostic capabilities. Both tune shifts due to beam neutralization and transversal beam-ion instabilities can be determined from the beam spectrum. Additionally the beam's transfer function can be measured using a broadband transversal kicker. In the stretcher ring at a beam energy of 1.2 GeV, a periodic beam blow-up was detected in the horizontal plane. Additional measurements of the transversal beam spectrum and ns-time resolution observations with a streak camera identified this blow-up as a coherent dipole oscillation of the beam. This horizontal instability is presumably caused by trapped ions, as there is a strong correlation with the high voltage-bias of the clearing electrodes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI016
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TUPRI044	Investigation of Microbunching-instability in BERLinPro	1662
	S.D. Rädel, A. Jankowiak, A. Meseck HZB, Berlin, Germany
	Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association BERLinPro is using the new energy recovery linac technology. As, maintaining the low emittance and energy spread is of major importance in an ERL, the deep understanding and control of effects which can degrade the emittance and energy spread such as space charge effects are of interest. The microbunching caused by the longitudinal space charge forces can lead to an increase in emittance and energy spread in the arcs of the loop. In this contribution, the impacts of the microbunching instability on the beam quality and its implication for BERLinPro are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI044
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TUPRI046	Dynamics of Ion Distributions in Beam Guiding Magnets	1668
	A. Markoviḱ, G. Pöplau, U. van Rienen Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany W. Hillert, D. Sauerland ELSA, Bonn, Germany A. Meseck HZB, Berlin, Germany
	Funding: Supported by the German Federal Ministry of Education and Research (BMBF) under contract number 05K13HRC. Ions generated by synchrotron radiation and collisions of the beam with the rest gas in the vacuum chamber could be a limiting factor for the operation of electron storage rings and Energy Recovery Linacs (ERL). In order to develop beam instability mitigation strategies, a deeper understanding of the ion-cloud behaviour is needed. Numerical simulations of the interaction between electron beams and parasitic ions verified with dedicated measurements can help to acquire that knowledge. This paper presents results of detailed simulations of the interaction in quadrupole magnets and drift sections of the Electron Stretcher Accelerator ELSA in Bonn. The focus is on the evaluation of the dynamics of different ion species and their characteristic distribution in quadrupole magnets.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI046
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Paper

Title

Page

Status of the HZB ERL Prototype BERLinPro

340

M. Abo-Bakr, W. Anders, R. Barday, K.B. Bürkmann-Gehrlein, A. Burrill, V. Dürr, A. Jankowiak, C. Kalus, T. Kamps, G. Klemz, J. Knobloch, J. Kolbe, O. Kugeler, B.C. Kuske, A.N. Matveenko, A. Meseck, A. Neumann, K. Ott, E. Panofski, D. Pflückhahn, J. Rahn, J. Rudolph, M. Schmeißer, S.G. Schubert, O. Schüler, J. Völker, S. Wesch
HZB, Berlin, Germany

Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association.
The Berlin Energy Recovery Linac Prototype BERLinPro is to be constructed at the Helmholtz Zentrum site in Berlin. The aim of the project is to expand the required accelerator physics and technology knowledge mandatory for the generation of a high current (100 mA), high brilliance (norm. emittance below 1 mm mrad) cw electron beam. Since the funding decision in October 2010 the project has entered a phase of detailed planning. Hardware specifications have been defined and various components have been ordered. Furthermore, extensive tests of principal superconducting accelerator components successfully demonstrated the envisaged hardware performance. A summary of the most recent activities together with the details of the project timeline for the coming years are given in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRO106

Export •

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

TUPRI016

First Studies on Ion Effects in the Accelerator ELSA

1585

D. Sauerland, W. Hillert, M.T. Switka
ELSA, Bonn, Germany
A. Markoviḱ, U. van Rienen
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
A. Meseck
HZB, Berlin, Germany

Funding: BMBF (Federal Ministry of Education and Research)
In the ELSA stretcher ring electrons are accelerated by a fast energy ramp of 6 GeV/s to a beam energy of 3.2 GeV. The high energetic electrons ionize the residual gas molecules in the beam pipe by collisions or synchrotron radiation. The generated ions in turn accumulate inside the beam potential, causing several undesired effects such as tune shifts and beam instabilities. These effects are studied experimentally at ELSA using its full diagnostic capabilities. Both tune shifts due to beam neutralization and transversal beam-ion instabilities can be determined from the beam spectrum. Additionally the beam's transfer function can be measured using a broadband transversal kicker. In the stretcher ring at a beam energy of 1.2 GeV, a periodic beam blow-up was detected in the horizontal plane. Additional measurements of the transversal beam spectrum and ns-time resolution observations with a streak camera identified this blow-up as a coherent dipole oscillation of the beam. This horizontal instability is presumably caused by trapped ions, as there is a strong correlation with the high voltage-bias of the clearing electrodes.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI016

Export •

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

TUPRI044

Investigation of Microbunching-instability in BERLinPro

1662

S.D. Rädel, A. Jankowiak, A. Meseck
HZB, Berlin, Germany

Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association
BERLinPro is using the new energy recovery linac technology. As, maintaining the low emittance and energy spread is of major importance in an ERL, the deep understanding and control of effects which can degrade the emittance and energy spread such as space charge effects are of interest. The microbunching caused by the longitudinal space charge forces can lead to an increase in emittance and energy spread in the arcs of the loop. In this contribution, the impacts of the microbunching instability on the beam quality and its implication for BERLinPro are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI044

Export •

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

TUPRI046

Dynamics of Ion Distributions in Beam Guiding Magnets

1668

A. Markoviḱ, G. Pöplau, U. van Rienen
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
W. Hillert, D. Sauerland
ELSA, Bonn, Germany
A. Meseck
HZB, Berlin, Germany

Funding: Supported by the German Federal Ministry of Education and Research (BMBF) under contract number 05K13HRC.
Ions generated by synchrotron radiation and collisions of the beam with the rest gas in the vacuum chamber could be a limiting factor for the operation of electron storage rings and Energy Recovery Linacs (ERL). In order to develop beam instability mitigation strategies, a deeper understanding of the ion-cloud behaviour is needed. Numerical simulations of the interaction between electron beams and parasitic ions verified with dedicated measurements can help to acquire that knowledge. This paper presents results of detailed simulations of the interaction in quadrupole magnets and drift sections of the Electron Stretcher Accelerator ELSA in Bonn. The focus is on the evaluation of the dynamics of different ion species and their characteristic distribution in quadrupole magnets.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI046

Export •

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