IPAC2015 - List of Authors (Floettmann, K.)

Paper	Title	Page
MOPHA026	Present and Future Optical-to-Microwave Synchronization Systems at REGAE Facility for Electron Diffraction and Plasma Acceleration Experiments	833
	M. Titberidze, F.J. Grüner, A.R. Maier, B. Zeitler CFEL, Hamburg, Germany S.W. Epp MPSD, Hamburg, Germany M. Felber, K. Flöttmann, T. Lamb, U. Mavrič, J.M. Müller, H. Schlarb, C. Sydlo DESY, Hamburg, Germany F.J. Grüner, A.R. Maier, M. Titberidze Uni HH, Hamburg, Germany E. Janas Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	Relativistic Electron Gun for Atomic Explorations (REGAE) is a Radio Frequency (RF) driven linear accelerator. It uses frequency tripled short photon pulses (~ 35 fs) from the Titanium Sapphire (Ti:Sa.) Laser system in order to generate electron bunches from the photo-cathode. The electron bunches are accelerated up to ~ 5 MeV kinetic energy and compressed down to sub-10 fs using the so called ballistic bunching technique. REGAE currently is used for electron diffraction experiments (by Prof. R.J.D. Miller's Group). In near future within the collaboration of Laboratory for Laser- and beam-driven plasma Acceleration (LAOLA), REGAE will also be employed to externally inject electron bunches into laser driven linear plasma waves. Both experiments require very precise synchronization (sub-50 fs) of the photo-injector laser and RF reference. In this paper we present experimental results of the current and new optical to microwave synchronization systems in comparison. We also address some of the issues related to the current system and give an upper limit in terms of its long-term performance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA026
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MOPHA027	Transverse Emittance Measurement at REGAE	837
	M. Hachmann, K. Flöttmann DESY, Hamburg, Germany
	The linear accelerator REGAE at DESY produces short and low charged electron bunches, on the one hand to resolve the excitation transitions of atoms temporally by pump probe electron diffraction experiments and on the other hand to investigate principal mechanisms of laser plasma acceleration. For both cases a high quality electron beam is required which can be identified with a small beam emittance. A standard magnet scan is used for the emittance measurement which is in case of a low charged bunch most sensitive to the beam size determination (2nd central moment of a distribution). Therefore the diagnostic and a routine to calculate proper central moments of an arbitrary distribution will be introduced and discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA027
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TUPWA028	Simulation Results of the Beam Transport of Ultra-Short Electron Bunches in Existing Beam Transfer Lines to Sinbad	1466
	U. Dorda, R.W. Aßmann, K. Flöttmann, B. Marchetti, Y.C. Nie, J. Zhu DESY, Hamburg, Germany
	SINBAD, the upcoming accelerator R&D facility at DESY, will host multiple independent experiments on the production and acceleration of ultra-short bunches including plasma wakefield experiments. As a possible later upgrade the option to transport higher energy electrons (up to 800 MeV) or positrons (up to 400 MeV) from the existing DESY Linac 2 to the facility is studied. Though existing a possible connection using e.g. a part of the DESY synchrotron as a transfer line and other currently unused transfer-line, these machines were not designed for the desired longitudinal bunch compression and high peak current required by e.g. beam driven plasma wake-field experiments. Simulation results illustrate the modifications to the current layout that would have to be implemented and the corresponding achievable beam parameters are given.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA028
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TUPWA029	ARES: Accelerator Research Experiment at SINBAD	1469
	B. Marchetti, R.W. Aßmann, C. Behrens, R. Brinkmann, U. Dorda, K. Flöttmann, J. Grebenyuk, M. Hüning, Y.C. Nie, H. Schlarb, J. Zhu DESY, Hamburg, Germany
	ARES is a planned linear accelerator for R&D for production of ultra-short electron bunches. It will be hosted at the SINBAD facility, at DESY in Hamburg. The goal of ARES is to produce low charge (0.2-50pC), ultra-short (from few fs to sub-fs) bunches, with high arrival time stability (less than 10fs) for various applications, such as external injection for Laser Plasma Wake-Field acceleration. The baseline layout of the accelerator foresees an S-band photo-injector which compresses low charge electron bunches via velocity bunching and accelerates them to 100 MeV energy. In the second stage, it is planned to install a third S-band accelerating cavity to reach 200 MeV as well as two X-band cavities: One for the linearization of the longitudinal phase space (subsequently allowing an improved bunch compression) and another one as a transverse deflecting cavity for longitudinal beam diagnostics. Moreover a magnetic bunch compressor is envisaged allowing to cut out the central slice of the beam** or hybrid bunch compression. * R. Assmann et al., TUPME047, Proceedings of IPAC 2014. R. Assmann, J. Grebenyuk, TUOBB01, Proceedings of IPAC 2014. * P. Emma et al., PRL 92 7 (2004).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA029
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TUPWA042	Status of the Accelerator Physics Test Facility FLUTE	1506
	M.J. Nasse, A. Bernhard, I. Birkel, A. Borysenko, A. Böhm, S. Hillenbrand, N. Hiller, S. Höninger, S. Marsching, A.-S. Müller, R. Rossmanith, R. Ruprecht, M. Schuh, M. Schwarz, B. Smit, S. Walther, M. Weber, P. Wesolowski KIT, Karlsruhe, Germany R.W. Aßmann, M. Felber, K. Flöttmann, C. Gerth, M. Hoffmann, P. Peier, H. Schlarb, B. Steffen DESY, Hamburg, Germany R. Ischebeck, B. Keil, V. Schlott, L. Stingelin PSI, Villigen PSI, Switzerland
	A new compact versatile linear accelerator named FLUTE (Ferninfrarot Linac Und Test Experiment) is currently under construction at the Karlsruhe Institute of Technology (KIT). It will serve as an accelerator test facility and allow conducting a variety of accelerator physics studies. In addition, it will be used to generate intense, ultra-short THz pulses for photon science experiments. FLUTE consists of a ~7 MeV photo-injector gun, a ~41 MeV S-band linac and a D-shaped chicane to compress bunches to a few femtoseconds. This contribution presents an overview of the project status and the accompanying simulation studies.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA042
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WEPMA029	Design of a Normal Conducting Cavity for Arrival Time Stabilization at FLASH	2818
	M. Fakhari, K. Flöttmann, S. Pfeiffer, H. Schlarb DESY, Hamburg, Germany J. Roßbach Uni HH, Hamburg, Germany
	It has been shown, that beam-based feedback loops stabilize the bunch arrival time in the femtoseconds range. However, further minimizing the bunch arrival time jitter requires a faster actuator that is a normal conducting cavity with higher bandwidth compared to narrow-band superconducting cavities. We present the design of a 4-cell normal conducting cavity that is going to be used in a fast beam-based feedback at free-electron laser FLASH at Hamburg. The input power will be injected to the cavity via a loop coupler from the side of the first cell. The operating frequency of the designed cavity is about 3 GHz with an adjustable bandwidth. The long range longitudinal wakefield calculation results are reported to investigate the cavity performance for multi-beam operation up to 3 MHz bunch repetition rate. The results declare that the influence of the long range wakefield on the arrival time jitter is less than 1 fs.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMA029
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WEPMA030	Design and Characterization of Permanent Magnetic Solenoids for REGAE	2822
	M. Hachmann, K. Flöttmann, T. Gehrke, F. Mayet DESY, Hamburg, Germany
	REGAE is a small electron linear accelerator at DESY. In order to focus short and low charged electron bunches down to a few micrometre permanent magnetic solenoids were designed, assembled and field measurements were done. Due to a shortage of space close to the operation area an in-vacuum solution has been chosen. Furthermore a tworing design made of wedges has been preferred in terms of beam dynamic issues. To keep the field quality of a piecewise built magnet still high a sorting algorithm for the wedge arrangement has been developed and used for the construction of the magnets. The magnetic field of these solenoids has been measured with high precision and has been compared to the simulated magnetic field.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMA030
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Present and Future Optical-to-Microwave Synchronization Systems at REGAE Facility for Electron Diffraction and Plasma Acceleration Experiments

833

M. Titberidze, F.J. Grüner, A.R. Maier, B. Zeitler
CFEL, Hamburg, Germany
S.W. Epp
MPSD, Hamburg, Germany
M. Felber, K. Flöttmann, T. Lamb, U. Mavrič, J.M. Müller, H. Schlarb, C. Sydlo
DESY, Hamburg, Germany
F.J. Grüner, A.R. Maier, M. Titberidze
Uni HH, Hamburg, Germany
E. Janas
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

Relativistic Electron Gun for Atomic Explorations (REGAE) is a Radio Frequency (RF) driven linear accelerator. It uses frequency tripled short photon pulses (~ 35 fs) from the Titanium Sapphire (Ti:Sa.) Laser system in order to generate electron bunches from the photo-cathode. The electron bunches are accelerated up to ~ 5 MeV kinetic energy and compressed down to sub-10 fs using the so called ballistic bunching technique. REGAE currently is used for electron diffraction experiments (by Prof. R.J.D. Miller's Group). In near future within the collaboration of Laboratory for Laser- and beam-driven plasma Acceleration (LAOLA), REGAE will also be employed to externally inject electron bunches into laser driven linear plasma waves. Both experiments require very precise synchronization (sub-50 fs) of the photo-injector laser and RF reference. In this paper we present experimental results of the current and new optical to microwave synchronization systems in comparison. We also address some of the issues related to the current system and give an upper limit in terms of its long-term performance.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA026

Export •

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

MOPHA027

Transverse Emittance Measurement at REGAE

837

M. Hachmann, K. Flöttmann
DESY, Hamburg, Germany

The linear accelerator REGAE at DESY produces short and low charged electron bunches, on the one hand to resolve the excitation transitions of atoms temporally by pump probe electron diffraction experiments and on the other hand to investigate principal mechanisms of laser plasma acceleration. For both cases a high quality electron beam is required which can be identified with a small beam emittance. A standard magnet scan is used for the emittance measurement which is in case of a low charged bunch most sensitive to the beam size determination (2nd central moment of a distribution). Therefore the diagnostic and a routine to calculate proper central moments of an arbitrary distribution will be introduced and discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA027

Export •

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TUPWA028

Simulation Results of the Beam Transport of Ultra-Short Electron Bunches in Existing Beam Transfer Lines to Sinbad

1466

U. Dorda, R.W. Aßmann, K. Flöttmann, B. Marchetti, Y.C. Nie, J. Zhu
DESY, Hamburg, Germany

SINBAD, the upcoming accelerator R&D facility at DESY, will host multiple independent experiments on the production and acceleration of ultra-short bunches including plasma wakefield experiments. As a possible later upgrade the option to transport higher energy electrons (up to 800 MeV) or positrons (up to 400 MeV) from the existing DESY Linac 2 to the facility is studied. Though existing a possible connection using e.g. a part of the DESY synchrotron as a transfer line and other currently unused transfer-line, these machines were not designed for the desired longitudinal bunch compression and high peak current required by e.g. beam driven plasma wake-field experiments. Simulation results illustrate the modifications to the current layout that would have to be implemented and the corresponding achievable beam parameters are given.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA028

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

TUPWA029

ARES: Accelerator Research Experiment at SINBAD

1469

B. Marchetti, R.W. Aßmann, C. Behrens, R. Brinkmann, U. Dorda, K. Flöttmann, J. Grebenyuk, M. Hüning, Y.C. Nie, H. Schlarb, J. Zhu
DESY, Hamburg, Germany

ARES is a planned linear accelerator for R&D for production of ultra-short electron bunches. It will be hosted at the SINBAD facility, at DESY in Hamburg*. The goal of ARES is to produce low charge (0.2-50pC), ultra-short (from few fs to sub-fs) bunches, with high arrival time stability (less than 10fs) for various applications, such as external injection for Laser Plasma Wake-Field acceleration**. The baseline layout of the accelerator foresees an S-band photo-injector which compresses low charge electron bunches via velocity bunching and accelerates them to 100 MeV energy. In the second stage, it is planned to install a third S-band accelerating cavity to reach 200 MeV as well as two X-band cavities: One for the linearization of the longitudinal phase space (subsequently allowing an improved bunch compression) and another one as a transverse deflecting cavity for longitudinal beam diagnostics. Moreover a magnetic bunch compressor is envisaged allowing to cut out the central slice of the beam*** or hybrid bunch compression.
* R. Assmann et al., TUPME047, Proceedings of IPAC 2014.
** R. Assmann, J. Grebenyuk, TUOBB01, Proceedings of IPAC 2014.
*** P. Emma et al., PRL 92 7 (2004).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA029

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TUPWA042

Status of the Accelerator Physics Test Facility FLUTE

1506

M.J. Nasse, A. Bernhard, I. Birkel, A. Borysenko, A. Böhm, S. Hillenbrand, N. Hiller, S. Höninger, S. Marsching, A.-S. Müller, R. Rossmanith, R. Ruprecht, M. Schuh, M. Schwarz, B. Smit, S. Walther, M. Weber, P. Wesolowski
KIT, Karlsruhe, Germany
R.W. Aßmann, M. Felber, K. Flöttmann, C. Gerth, M. Hoffmann, P. Peier, H. Schlarb, B. Steffen
DESY, Hamburg, Germany
R. Ischebeck, B. Keil, V. Schlott, L. Stingelin
PSI, Villigen PSI, Switzerland

A new compact versatile linear accelerator named FLUTE (Ferninfrarot Linac Und Test Experiment) is currently under construction at the Karlsruhe Institute of Technology (KIT). It will serve as an accelerator test facility and allow conducting a variety of accelerator physics studies. In addition, it will be used to generate intense, ultra-short THz pulses for photon science experiments. FLUTE consists of a ~7 MeV photo-injector gun, a ~41 MeV S-band linac and a D-shaped chicane to compress bunches to a few femtoseconds. This contribution presents an overview of the project status and the accompanying simulation studies.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPWA042

Export •

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

WEPMA029

Design of a Normal Conducting Cavity for Arrival Time Stabilization at FLASH

2818

M. Fakhari, K. Flöttmann, S. Pfeiffer, H. Schlarb
DESY, Hamburg, Germany
J. Roßbach
Uni HH, Hamburg, Germany

It has been shown, that beam-based feedback loops stabilize the bunch arrival time in the femtoseconds range. However, further minimizing the bunch arrival time jitter requires a faster actuator that is a normal conducting cavity with higher bandwidth compared to narrow-band superconducting cavities. We present the design of a 4-cell normal conducting cavity that is going to be used in a fast beam-based feedback at free-electron laser FLASH at Hamburg. The input power will be injected to the cavity via a loop coupler from the side of the first cell. The operating frequency of the designed cavity is about 3 GHz with an adjustable bandwidth. The long range longitudinal wakefield calculation results are reported to investigate the cavity performance for multi-beam operation up to 3 MHz bunch repetition rate. The results declare that the influence of the long range wakefield on the arrival time jitter is less than 1 fs.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMA029

Export •

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

WEPMA030

Design and Characterization of Permanent Magnetic Solenoids for REGAE

2822

M. Hachmann, K. Flöttmann, T. Gehrke, F. Mayet
DESY, Hamburg, Germany

REGAE is a small electron linear accelerator at DESY. In order to focus short and low charged electron bunches down to a few micrometre permanent magnetic solenoids were designed, assembled and field measurements were done. Due to a shortage of space close to the operation area an in-vacuum solution has been chosen. Furthermore a tworing design made of wedges has been preferred in terms of beam dynamic issues. To keep the field quality of a piecewise built magnet still high a sorting algorithm for the wedge arrangement has been developed and used for the construction of the magnets. The magnetic field of these solenoids has been measured with high precision and has been compared to the simulated magnetic field.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMA030

Export •

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