IPAC2017 - List of Authors (Jankowiak, A.)

Paper	Title	Page
MOPVA005	Status of the Berlin Energy Recovery Linac Project BERLinPro	855
	M. Abo-Bakr, W. Anders, K.B. Bürkmann-Gehrlein, A.B. Büchel, P. Echevarria, A. Frahm, H.-W. Glock, F. Glöckner, F. Göbel, B.D.S. Hall, S. Heling, H.-G. Hoberg, A. Jankowiak, C. Kalus, T. Kamps, G. Klemz, J. Knedel, J. Knobloch, J. Kolbe, G. Kourkafas, J. Kühn, B.C. Kuske, J. Kuszynski, D. Malyutin, A.N. Matveenko, M. McAteer, A. Meseck, C.J. Metzger-Kraus, R. Müller, A. Neumann, N. Ohm, K. Ott, E. Panofski, F. Pflocksch, J. Rahn, M. Schmeißer, O. Schüler, M. Schuster, J. Ullrich, A. Ushakov, J. Völker HZB, Berlin, Germany
	Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association. The Helmholtz-Zentrum Berlin is constructing the Energy Recovery Linac Prototype BERLinPro, a demonstration facility for the science and technology of ERLs for future light source applications. BERLinPro is designed to accelerate a high current (100 mA, 50 MeV), high brilliance (norm. emittance below 1 mm mrad) cw electron beam. We report on the project status. This includes the completion of the building and the installation of the first accelerator components as well as the assembly of the SRF gun and GunLab beam diagnostics, which are now ready for commissioning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA005
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPVA010	Setup and Status of an SRF Photoinjector for Energy-Recovery Linac Applications	865
	T. Kamps, D. Böhlick, A.B. Büchel, M. Bürger, P. Echevarria, A. Frahm, F. Göbel, S. Heling, A. Jankowiak, S. Keckert, H. Kirschner, G. Klemz, J. Knobloch, G. Kourkafas, J. Kühn, O. Kugeler, A.N. Matveenko, A. Neumann, N. Ohm-Krafft, E. Panofski, F. Pfloksch, S. Rotterdam, M.A.H. Schmeißer, M. Schuster, H. Stein, J. Ullrich, A. Ushakov, J. Völker HZB, Berlin, Germany I. Will MBI, Berlin, Germany
	Funding: The work is funded by the Helmholtz-Association, BMBF, the state of Berlin and HZB. The Superconducting RF (SRF) photoinjector programme for the energy-recovery linac (ERL) test facility BERLinPro sets out to push the brightness and average current limits for ERL electron sources by tackling the main challenges related to beam dynamics of SRF photoinjectors, the incorporation of high quantum efficiency (QE) photocathodes, and suppression of unwanted beam generation. The paper details the experimental layout of the SRF photoinjector and the gun test facility GunLab at Helmholtz-Zentrum Berlin.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA010
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAB028	Measuring the Spectral Response of Cs-K-Sb Photocathodes for BERLinPro	1378
	H. Kirschner, A. Jankowiak, T. Kamps, J. Kühn, M.A.H. Schmeißer HZB, Berlin, Germany
	A spectral response setup was commissioned at the Cs-K-Sb photocathode preparation and analysis system developed for the BERLinPro project. The setup is designed to measure the spectral quantum efficiency from 370 to 700 nm and to monitor the photocurrent during the photocathode growth process and the photocathode lifetime at 515 nm.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPAB028
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAB029	UHV Photocathode Plug Transfer Chain for the BERLinPro SRF-Photoinjector	1381
	J. Kühn, J. Borninkhof, M. Bürger, A. Frahm, A. Jankowiak, T. Kamps, M.A.H. Schmeißer, M. Schuster HZB, Berlin, Germany P. Murcek, J. Teichert, R. Xiang HZDR, Dresden, Germany
	A dedicated particle free UHV photocathode plug transfer chain from the preparation system to the SRF-Photoinjector was set up and commissioned at HZB for the BERLinPro project. The plug handling system was designed in collaboration with the ELBE team at HZDR, where the same transfer chain is in commissioning phase. In the future the exchange of photocathodes between the laboratories offers the possibility to test different types of photocathodes in different SRF-photoinjectors.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPAB029
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPIK042	Solenoid Alignment for the SRF Photoinjector of BERLinPro at HZB	1778
	G. Kourkafas, A. Jankowiak, T. Kamps, J. Li, J. Völker HZB, Berlin, Germany M. Schebek Humboldt University Berlin, Berlin, Germany
	The Berlin Energy Recovery Linac Prototype (BERLinPro) at Helmholtz Zentrum Berlin (HZB) aims to deliver a continuous-wave (cw) electron beam of high average current (100 mA) and brilliance (normalized emittance below 1 mm mrad). The achievement of these demanding goals depends significantly on the performance of the electron source, a superconducting RF (SRF) photoinjector. A critical component for the quality of the generated beam is the superconducting solenoid magnet. In order to optimize its operation and minimize parasitic contributions, special attention has been given to the precise alignment of this element using a hexapod mover. Due to the strict limitations inside a cryostat, a complex coupling between the solenoid in vacuum and the hexapod in air has been realized, requiring sophisticated software and hardware mechanisms to prevent collisions. Along with this setup, the developed beam-based alignment procedure and its performance are demonstrated in this article.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK042
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
Export •	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
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPAB009	Multi-Objective Optimization of an SRF Photoinjector for ERL and UED Applications	3704
SUSPSIK065	use link to see paper's listing under its alternate paper code
	E. Panofski, A. Jankowiak, T. Kamps, G. Kourkafas HZB, Berlin, Germany S. Eisebitt MBI, Berlin, Germany
	Superconducting RF photoinjectors, running in continuous-wave (cw) mode, are able to generate electron beams of high average brightness and ultra-short bunches. Therefore, they satisfy the requirements of future accelerator facilities, such as energy recovery linacs (ERL). Further, SRF guns are able to provide relativistic probe beams for ultrafast electron diffraction (UED). Choosing suitable values for the drive laser, cavity and solenoid settings poses a great challenge for the injector commissioning and operation. Using multi-objective optimization based on an evolutionary algorithm, optimum gun parameter settings are extracted from Pareto-optimum solutions. The development of a universal multi-objective optimization algorithm for SRF photoinjectors as well as first Pareto optimum results for an ERL and UED application of GunLab, the compact SRF gun test facility at Helmholtz-Zentrum Berlin, will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB009
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)

Paper

Title

Page

Status of the Berlin Energy Recovery Linac Project BERLinPro

855

M. Abo-Bakr, W. Anders, K.B. Bürkmann-Gehrlein, A.B. Büchel, P. Echevarria, A. Frahm, H.-W. Glock, F. Glöckner, F. Göbel, B.D.S. Hall, S. Heling, H.-G. Hoberg, A. Jankowiak, C. Kalus, T. Kamps, G. Klemz, J. Knedel, J. Knobloch, J. Kolbe, G. Kourkafas, J. Kühn, B.C. Kuske, J. Kuszynski, D. Malyutin, A.N. Matveenko, M. McAteer, A. Meseck, C.J. Metzger-Kraus, R. Müller, A. Neumann, N. Ohm, K. Ott, E. Panofski, F. Pflocksch, J. Rahn, M. Schmeißer, O. Schüler, M. Schuster, J. Ullrich, A. Ushakov, J. Völker
HZB, Berlin, Germany

Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association.
The Helmholtz-Zentrum Berlin is constructing the Energy Recovery Linac Prototype BERLinPro, a demonstration facility for the science and technology of ERLs for future light source applications. BERLinPro is designed to accelerate a high current (100 mA, 50 MeV), high brilliance (norm. emittance below 1 mm mrad) cw electron beam. We report on the project status. This includes the completion of the building and the installation of the first accelerator components as well as the assembly of the SRF gun and GunLab beam diagnostics, which are now ready for commissioning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA005

Export •

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

MOPVA010

Setup and Status of an SRF Photoinjector for Energy-Recovery Linac Applications

865

T. Kamps, D. Böhlick, A.B. Büchel, M. Bürger, P. Echevarria, A. Frahm, F. Göbel, S. Heling, A. Jankowiak, S. Keckert, H. Kirschner, G. Klemz, J. Knobloch, G. Kourkafas, J. Kühn, O. Kugeler, A.N. Matveenko, A. Neumann, N. Ohm-Krafft, E. Panofski, F. Pfloksch, S. Rotterdam, M.A.H. Schmeißer, M. Schuster, H. Stein, J. Ullrich, A. Ushakov, J. Völker
HZB, Berlin, Germany
I. Will
MBI, Berlin, Germany

Funding: The work is funded by the Helmholtz-Association, BMBF, the state of Berlin and HZB.
The Superconducting RF (SRF) photoinjector programme for the energy-recovery linac (ERL) test facility BERLinPro sets out to push the brightness and average current limits for ERL electron sources by tackling the main challenges related to beam dynamics of SRF photoinjectors, the incorporation of high quantum efficiency (QE) photocathodes, and suppression of unwanted beam generation. The paper details the experimental layout of the SRF photoinjector and the gun test facility GunLab at Helmholtz-Zentrum Berlin.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA010

Export •

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

TUPAB028

Measuring the Spectral Response of Cs-K-Sb Photocathodes for BERLinPro

1378

H. Kirschner, A. Jankowiak, T. Kamps, J. Kühn, M.A.H. Schmeißer
HZB, Berlin, Germany

A spectral response setup was commissioned at the Cs-K-Sb photocathode preparation and analysis system developed for the BERLinPro project. The setup is designed to measure the spectral quantum efficiency from 370 to 700 nm and to monitor the photocurrent during the photocathode growth process and the photocathode lifetime at 515 nm.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPAB028

Export •

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

TUPAB029

UHV Photocathode Plug Transfer Chain for the BERLinPro SRF-Photoinjector

1381

J. Kühn, J. Borninkhof, M. Bürger, A. Frahm, A. Jankowiak, T. Kamps, M.A.H. Schmeißer, M. Schuster
HZB, Berlin, Germany
P. Murcek, J. Teichert, R. Xiang
HZDR, Dresden, Germany

A dedicated particle free UHV photocathode plug transfer chain from the preparation system to the SRF-Photoinjector was set up and commissioned at HZB for the BERLinPro project. The plug handling system was designed in collaboration with the ELBE team at HZDR, where the same transfer chain is in commissioning phase. In the future the exchange of photocathodes between the laboratories offers the possibility to test different types of photocathodes in different SRF-photoinjectors.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPAB029

Export •

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

TUPIK042

Solenoid Alignment for the SRF Photoinjector of BERLinPro at HZB

1778

G. Kourkafas, A. Jankowiak, T. Kamps, J. Li, J. Völker
HZB, Berlin, Germany
M. Schebek
Humboldt University Berlin, Berlin, Germany

The Berlin Energy Recovery Linac Prototype (BERLinPro) at Helmholtz Zentrum Berlin (HZB) aims to deliver a continuous-wave (cw) electron beam of high average current (100 mA) and brilliance (normalized emittance below 1 mm mrad). The achievement of these demanding goals depends significantly on the performance of the electron source, a superconducting RF (SRF) photoinjector. A critical component for the quality of the generated beam is the superconducting solenoid magnet. In order to optimize its operation and minimize parasitic contributions, special attention has been given to the precise alignment of this element using a hexapod mover. Due to the strict limitations inside a cryostat, a complex coupling between the solenoid in vacuum and the hexapod in air has been realized, requiring sophisticated software and hardware mechanisms to prevent collisions. Along with this setup, the developed beam-based alignment procedure and its performance are demonstrated in this article.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK042

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

Export •

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

Export •

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

THPAB009

Multi-Objective Optimization of an SRF Photoinjector for ERL and UED Applications

3704

SUSPSIK065

use link to see paper's listing under its alternate paper code

E. Panofski, A. Jankowiak, T. Kamps, G. Kourkafas
HZB, Berlin, Germany
S. Eisebitt
MBI, Berlin, Germany

Superconducting RF photoinjectors, running in continuous-wave (cw) mode, are able to generate electron beams of high average brightness and ultra-short bunches. Therefore, they satisfy the requirements of future accelerator facilities, such as energy recovery linacs (ERL). Further, SRF guns are able to provide relativistic probe beams for ultrafast electron diffraction (UED). Choosing suitable values for the drive laser, cavity and solenoid settings poses a great challenge for the injector commissioning and operation. Using multi-objective optimization based on an evolutionary algorithm, optimum gun parameter settings are extracted from Pareto-optimum solutions. The development of a universal multi-objective optimization algorithm for SRF photoinjectors as well as first Pareto optimum results for an ERL and UED application of GunLab, the compact SRF gun test facility at Helmholtz-Zentrum Berlin, will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB009

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)