IPAC2017 - List of Authors (Ries, M.)

Paper	Title	Page
MOPAB031	Orbit Measurements in the BESSY II Booster in Preparation for Quasi-Low-Alpha Operation	146
	T. Atkinson, E. Motuk, M. Ries, M. Ulrich HZB, Berlin, Germany
	Diagnostic refurbishments are ongoing in the booster synchrotron in preparation for the near future Variable pulse Storage Ring (VSR) project at BESSY II. Essential orbit measurements have been re-installed after almost two decades of latency. This diagnostic will help assess the effectiveness of the possible upgrade scenarios such as quasi-low-alpha operation and extraction optimization. The contribution presents the preliminary results of the continual global upgrade of the injector systems.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB031
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MOPAB032	Status of a Double Slit Interferometer for Transverse Beam Size Measurements at BESSY II	149
	M. Koopmans, P. Goslawski, J.G. Hwang, M. Ries, M. Ruprecht, A. Schälicke HZB, Berlin, Germany
	Funding: Work supported by the German Bundesministerium für Bildung und Forschung, Land Berlin and grants of Helmholtz Association The upgrade of the BESSY II storage ring to BESSY VSR* demands additional beam diagnostics for machine commissioning and development. Especially bunch resolved measurements are needed. Currently, transverse beam size measurements are done with X-ray pinhole monitor systems, which cannot provide bunch resolved information. Alternative methods to measure the transverse beam size using synchrotron radiation in the visible spectrum are interferometric techniques, which could also be upgraded to bunch resolved systems. For that purpose a double slit interferometer has been constructed. Commissioning of the system has started and experimental results are discussed and compared with the existing pinhole system. * A. Jankowiak et al., eds., ''BESSY VSR - Technical Design Study'', Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Germany, June 2015.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB032
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WEPAB007	Pseudo Single Bunch Qualities Added to Short Pulse Operation of BESSY II	2574
	R. Müller, T. Birke, F. Falkenstern, K. Holldack, A. Jankowiak, M. Ries, A. Schälicke HZB, Berlin, Germany
	Funding: Work supported by the German Bundesministerium für Bildung und Forschung, Land Berlin and grants of Helmholtz Association BESSY II features sophisticated filling patterns as well as manipulation and separation techniques of custom bunches to serve both timing and photon hungry experiments at the same time. Recently, the low alpha operation mode, providing bunch lengths as short as 2 ps, was extended by pseudo single bunch options. A robust technique to excite one bunch with constant displacement and enlargement was implemented for pulse picking by resonant excitation (PPRE)* users. In addition, reliable scraping of an isolated bunch to provide zero current bunch length is opening new timing opportunities. The simultaneous usage of different photon characteristics: high intensity CSR, non-bursting CSR, short duration as well as operation mode specific X-rays impose new challenges. Sensitive tune measurements and feedback mechanisms had to be developed for all three dimensions. Negative alpha is in consideration to overcome the top up efficiency constraints. R. Müller et.al. BESSY II Supports an Extensive Suite of Timing Experiments, IPAC16 *K. Holldack et.al. Single bunch X-ray pulses on demand from a multi-bunch SR source, Nature Comm.5, 2014
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB007
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WEPIK056	Compensation of Transient Beam Loading with Detuned Cavities at BESSY II	3056
	M. Ruprecht, P. Goslawski, F. Kramer, M. Ries HZB, Berlin, Germany
	This paper presents operational experience and use cases of cavity operation in the synchrotron light source BESSY II, where an active or passive cavity is detuned by a small fraction of the harmonic number. If the detuning is an integer multiple of the fundamental RF harmonic, the distortion of the longitudinal phase space is periodic with the revolution, which allows for the compensation of fill pattern induced transients. Measurements at BESSY II are presented, where a fundamental cavity is detuned to decrease the effects of transient beam loading. Thus, reducing the phase transient and increasing the beam life time. Calculations depicting the application of this scheme for the future project BESSY VSR[] are presented. A. Jankowiak, J. Knobloch, P. Goslawski, and N. Neumann, eds., BESSY VSR - Technical Design Study, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 2015.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK056
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WEPIK057	Transverse Resonance Island Buckets as Bunch Separation Scheme	3059
	P. Goslawski, A. Jankowiak, F. Kramer, M. Ries, M. Ruprecht, G. Wüstefeld HZB, Berlin, Germany
	Funding: Supported by the BMBF Beam storage close to a tune resonance (Qx = 1/3,1/4) can generate transverse resonance island buckets in the x,x' phase space providing a second stable island orbit winding around the standard orbit. The two orbits are well separated, with good life time and stability. Successful user experiments have been conducted at BESSY II and the Metrology Light Source (MLS) ,* with such an operation mode. We discuss the required beam optics setup, the TopUp injection process and present successful measurements taken at photon beamlines at BESSY II. * THPMR017, P.Goslawski et al., IPAC2016, Busan, Korea ** MOPWA021, M.Ries et al., IPAC2015, Richmond, USA
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK057
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THPAB008	Particle Swarm Optimization Algorithm Applied in Online Commissioning at the MLS and BESSY II	3700
	J. Li, J. Feikes, P. Goslawski, M. Ries HZB, Berlin, Germany
	Particle Swarm Optimization (PSO) is a population based optimization technique inspired by the social behaviour of bird flocking. This algorithm has been successfully used for beam dynamics simulation due to its excellent capability to deal with large-dimensional optimization problems. At the MLS and BESSY II PSO was first successfully applied to improve the lifetime by 20~30% within only 10 iterations respectively. Now the PSO has been implemented as a multifunctional online optimizer to improve the machine performance. This paper presents some results of online experiments.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB008
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THPIK013	Renewal of Bessy Ii Rf System - Solid State Amplifiers and Hom Damped Cavities	4127
	W. Anders, P. Goslawski, A. Heugel, H.-G. Hoberg, H. Hoffmann, A. Jankowiak, J. Knobloch, G. Mielczarek, M. Ries, M. Ruprecht, A. Schälicke, B. Schriefer, H. Stein HZB, Berlin, Germany M. Haucke Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), Berlin, Germany K. Ludwig BESSY GmbH, Berlin, Germany
	Due to the fact that the klystrons run out of production and due to the aging of the old cavities, a renewal of the RF system was necessary. Solid state based transmitters and HOM damped nc single cell cavities have been installed at the BESSY II storage ring. The parameters of the components, the installation phase and the results to the beam will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK013
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Paper

Title

Page

Orbit Measurements in the BESSY II Booster in Preparation for Quasi-Low-Alpha Operation

146

T. Atkinson, E. Motuk, M. Ries, M. Ulrich
HZB, Berlin, Germany

Diagnostic refurbishments are ongoing in the booster synchrotron in preparation for the near future Variable pulse Storage Ring (VSR) project at BESSY II. Essential orbit measurements have been re-installed after almost two decades of latency. This diagnostic will help assess the effectiveness of the possible upgrade scenarios such as quasi-low-alpha operation and extraction optimization. The contribution presents the preliminary results of the continual global upgrade of the injector systems.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB031

Export •

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

MOPAB032

Status of a Double Slit Interferometer for Transverse Beam Size Measurements at BESSY II

149

M. Koopmans, P. Goslawski, J.G. Hwang, M. Ries, M. Ruprecht, A. Schälicke
HZB, Berlin, Germany

Funding: Work supported by the German Bundesministerium für Bildung und Forschung, Land Berlin and grants of Helmholtz Association
The upgrade of the BESSY II storage ring to BESSY VSR* demands additional beam diagnostics for machine commissioning and development. Especially bunch resolved measurements are needed. Currently, transverse beam size measurements are done with X-ray pinhole monitor systems, which cannot provide bunch resolved information. Alternative methods to measure the transverse beam size using synchrotron radiation in the visible spectrum are interferometric techniques, which could also be upgraded to bunch resolved systems. For that purpose a double slit interferometer has been constructed. Commissioning of the system has started and experimental results are discussed and compared with the existing pinhole system.
* A. Jankowiak et al., eds., ''BESSY VSR - Technical Design Study'', Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Germany, June 2015.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB032

Export •

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

WEPAB007

Pseudo Single Bunch Qualities Added to Short Pulse Operation of BESSY II

2574

R. Müller, T. Birke, F. Falkenstern, K. Holldack, A. Jankowiak, M. Ries, A. Schälicke
HZB, Berlin, Germany

Funding: Work supported by the German Bundesministerium für Bildung und Forschung, Land Berlin and grants of Helmholtz Association
BESSY II features sophisticated filling patterns as well as manipulation and separation techniques of custom bunches to serve both timing and photon hungry experiments at the same time*. Recently, the low alpha operation mode, providing bunch lengths as short as 2 ps, was extended by pseudo single bunch options. A robust technique to excite one bunch with constant displacement and enlargement was implemented for pulse picking by resonant excitation (PPRE)** users. In addition, reliable scraping of an isolated bunch to provide zero current bunch length is opening new timing opportunities. The simultaneous usage of different photon characteristics: high intensity CSR, non-bursting CSR, short duration as well as operation mode specific X-rays impose new challenges. Sensitive tune measurements and feedback mechanisms had to be developed for all three dimensions. Negative alpha is in consideration to overcome the top up efficiency constraints.
*R. Müller et.al. BESSY II Supports an Extensive Suite of Timing Experiments, IPAC16
**K. Holldack et.al. Single bunch X-ray pulses on demand from a multi-bunch SR source, Nature Comm.5, 2014

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB007

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WEPIK056

Compensation of Transient Beam Loading with Detuned Cavities at BESSY II

3056

M. Ruprecht, P. Goslawski, F. Kramer, M. Ries
HZB, Berlin, Germany

This paper presents operational experience and use cases of cavity operation in the synchrotron light source BESSY II, where an active or passive cavity is detuned by a small fraction of the harmonic number. If the detuning is an integer multiple of the fundamental RF harmonic, the distortion of the longitudinal phase space is periodic with the revolution, which allows for the compensation of fill pattern induced transients. Measurements at BESSY II are presented, where a fundamental cavity is detuned to decrease the effects of transient beam loading. Thus, reducing the phase transient and increasing the beam life time. Calculations depicting the application of this scheme for the future project BESSY VSR[*] are presented.
* A. Jankowiak, J. Knobloch, P. Goslawski, and N. Neumann, eds., BESSY VSR - Technical Design Study, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 2015.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK056

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

WEPIK057

Transverse Resonance Island Buckets as Bunch Separation Scheme

3059

P. Goslawski, A. Jankowiak, F. Kramer, M. Ries, M. Ruprecht, G. Wüstefeld
HZB, Berlin, Germany

Funding: Supported by the BMBF
Beam storage close to a tune resonance (Qx = 1/3,1/4) can generate transverse resonance island buckets in the x,x' phase space providing a second stable island orbit winding around the standard orbit. The two orbits are well separated, with good life time and stability. Successful user experiments have been conducted at BESSY II and the Metrology Light Source (MLS) *,** with such an operation mode. We discuss the required beam optics setup, the TopUp injection process and present successful measurements taken at photon beamlines at BESSY II.
* THPMR017, P.Goslawski et al., IPAC2016, Busan, Korea
** MOPWA021, M.Ries et al., IPAC2015, Richmond, USA

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK057

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THPAB008

Particle Swarm Optimization Algorithm Applied in Online Commissioning at the MLS and BESSY II

3700

J. Li, J. Feikes, P. Goslawski, M. Ries
HZB, Berlin, Germany

Particle Swarm Optimization (PSO) is a population based optimization technique inspired by the social behaviour of bird flocking. This algorithm has been successfully used for beam dynamics simulation due to its excellent capability to deal with large-dimensional optimization problems. At the MLS and BESSY II PSO was first successfully applied to improve the lifetime by 20~30% within only 10 iterations respectively. Now the PSO has been implemented as a multifunctional online optimizer to improve the machine performance. This paper presents some results of online experiments.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB008

Export •

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

THPIK013

Renewal of Bessy Ii Rf System - Solid State Amplifiers and Hom Damped Cavities

4127

W. Anders, P. Goslawski, A. Heugel, H.-G. Hoberg, H. Hoffmann, A. Jankowiak, J. Knobloch, G. Mielczarek, M. Ries, M. Ruprecht, A. Schälicke, B. Schriefer, H. Stein
HZB, Berlin, Germany
M. Haucke
Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), Berlin, Germany
K. Ludwig
BESSY GmbH, Berlin, Germany

Due to the fact that the klystrons run out of production and due to the aging of the old cavities, a renewal of the RF system was necessary. Solid state based transmitters and HOM damped nc single cell cavities have been installed at the BESSY II storage ring. The parameters of the components, the installation phase and the results to the beam will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK013

Export •

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