IPAC2018 - List of Authors (D'Arcy, R.T.P.)

Paper	Title	Page
TUPML017	Longitudinal Phase Space Reconstruction at FLASHForward Using a Novel Transverse Deflection Cavity, PolariX-TDS	1567
	R.T.P. D'Arcy, A. Aschikhin, P. González Caminal, V. Libov, J. Osterhoff DESY, Hamburg, Germany
	The FLASHForward project at DESY is an innovative beam-driven plasma-wakefield acceleration (PWFA) experiment, aiming to accelerate electron beams to GeV energies over a few centimeters of ionized gas. These accelerated beams are assessed for their capability to drive a free-electron laser. The ultra short, low emittance, and low energy spread properties of bunches produced from certain PWFA injection schemes naturally lend themselves to this task. However, these bunch lengths, typically in the few femtosecond range, are difficult to temporally resolve with traditional diagnostic methods. In order to longitudinally diagnose these bunches it is necessary to utilise the properties of a transverse RF deflecting cavity operating in a high-frequency regime. It is proposed that this type of X-band transverse deflection system, styled the PolariX-TDS due to its novel variable polarisation feature, will be introduced to the FLASHForward beam line in order to perform these single-shot longitudinal phase space measurements. This paper will concern itself with the efficacy of longitudinally reconstructing PWFA-bunches expected at FLASHForward with this TDS, with a focus on the variable bunch properties expected from early commissioning of the experiment.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML017
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TUPML040	Status of the Transverse Diagnostics at FLASHForward	1630
	P. Niknejadi, R.T.P. D'Arcy, A. Knetsch, V. Libov, A. Martinez de la Ossa, J. Osterhoff, K. Poder, L. Schaper DESY, Hamburg, Germany M. Kaluza, M.B. Schwab, A. Sävert, C. Wirth IOQ, Jena, Germany M. Kaluza HIJ, Jena, Germany T.J. Mehrling LBNL, Berkeley, USA C.A.J. Palmer Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
	Funding: Helmholtz Institute, Bundesministerium für Bildung und Forschung, and European Union‘s Horizon 2020 research and innovation program. Density modulations in plasma caused by a high-intensity laser or a high charge density electron pulse can generate extreme acceleration fields. Acceleration of electrons in such fields may produce ultra-relativistic, quasi-monoenergetic, ultra-short electron bunches over distances orders of magnitudes shorter than in state-of-the-art radio-frequency accelerators. FLASHForward is such a beam-driven plasma wakefield accelerator (PWFA) project at DESY with the goal of producing, characterizing, and utilizing such beams. Temporal characterization of the acceleration process is of crucial importance for improving the stability and control in PWFA beams. While measurement of the transient field of the femtosecond bunch in a single shot is challenging, in recent years novel techniques with great promise have been developed . This work discusses the plans and status of the transverse diagnostics at FLASHForward. A. Aschikhin et. al., NIMA , Volume 806 (11 January 2016) pp. 175-183. A. Buck et al., Nature Physics 7, (2011) 543. *C. J. Zhang et al., Phys. Rev. Lett. 119 (2017) 064801.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML040
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WEPAF050	Simulations of 3D Charge Density Measurements for Commissioning of the PolariX-TDS	1930
SUSPF104	use link to see paper's listing under its alternate paper code
	D. Marx, R.W. Aßmann, R.T.P. D'Arcy, B. Marchetti DESY, Hamburg, Germany
	The prototype of a novel X-band transverse deflection structure, the Polarizable X-band (PolariX) TDS, is currently being prepared for installation in the FLASHForward beamline* at DESY in early 2019. This structure will have the novel feature of variable polarization of the deflecting mode, allowing bunches to be streaked at any transverse angle, rather than at just one angle as in a conventional cavity. By combining screen profiles from several streaking angles using tomographic reconstruction techniques, the full 3D charge density of a bunch can be obtained**. It is planned to perform this measurement for the first time during commissioning of the structure. In this paper, simulations of this measurement are presented and the effects of jitter are discussed. P Craievich et al. paper THPAL068, this conference A Aschikhin et al. Nucl. Instr. Meth. Phys. Res. A., vol.806, pp.175-183, 2018 *D Marx et al. J. Phys.: Conf. Ser., vol.874, p.012077, 2017
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAF050
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THPAL068	Status of the Polarix-TDS Project	3808
	P. Craievich, M. Bopp, H.-H. Braun, R. Ganter, T. Kleeb, M. Pedrozzi, E. Prat, S. Reiche, R. Zennaro PSI, Villigen PSI, Switzerland R.W. Aßmann, F. Christie, R.T.P. D'Arcy, U. Dorda, M. Foese, P. González Caminal, M. Hoffmann, M. Hüning, R. Jonas, O. Krebs, S. Lederer, V. Libov, B. Marchetti, D. Marx, J. Osterhoff, F. Poblotzki, M. Reukauff, H. Schlarb, S. Schreiber, G. Tews, M. Vogt, A. Wagner DESY, Hamburg, Germany N. Catalán Lasheras, A. Grudiev, G. McMonagle, W. Wuensch CERN, Geneva, Switzerland
	A collaboration between DESY, PSI and CERN has been established to develop and build an advanced modular X-band transverse deflection structure (TDS) system with the new feature of providing variable polarization of the deflecting force. This innovative CERN design requires very high manufacturing precision to guarantee highest azimuthal symmetry of the structure to avoid the deterioration of the polarization of the streaking field. Therefore, the high-precision tuning-free production process developed at PSI for the C-band and X-band accelerating structures will be used for the manufacturing. We summarize in this paper the status of the production of the prototype and the waveguide networks foreseen in the different facilities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL068
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Paper

Title

Page

Longitudinal Phase Space Reconstruction at FLASHForward Using a Novel Transverse Deflection Cavity, PolariX-TDS

1567

R.T.P. D'Arcy, A. Aschikhin, P. González Caminal, V. Libov, J. Osterhoff
DESY, Hamburg, Germany

The FLASHForward project at DESY is an innovative beam-driven plasma-wakefield acceleration (PWFA) experiment, aiming to accelerate electron beams to GeV energies over a few centimeters of ionized gas. These accelerated beams are assessed for their capability to drive a free-electron laser. The ultra short, low emittance, and low energy spread properties of bunches produced from certain PWFA injection schemes naturally lend themselves to this task. However, these bunch lengths, typically in the few femtosecond range, are difficult to temporally resolve with traditional diagnostic methods. In order to longitudinally diagnose these bunches it is necessary to utilise the properties of a transverse RF deflecting cavity operating in a high-frequency regime. It is proposed that this type of X-band transverse deflection system, styled the PolariX-TDS due to its novel variable polarisation feature, will be introduced to the FLASHForward beam line in order to perform these single-shot longitudinal phase space measurements. This paper will concern itself with the efficacy of longitudinally reconstructing PWFA-bunches expected at FLASHForward with this TDS, with a focus on the variable bunch properties expected from early commissioning of the experiment.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML017

Export •

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

TUPML040

Status of the Transverse Diagnostics at FLASHForward

1630

P. Niknejadi, R.T.P. D'Arcy, A. Knetsch, V. Libov, A. Martinez de la Ossa, J. Osterhoff, K. Poder, L. Schaper
DESY, Hamburg, Germany
M. Kaluza, M.B. Schwab, A. Sävert, C. Wirth
IOQ, Jena, Germany
M. Kaluza
HIJ, Jena, Germany
T.J. Mehrling
LBNL, Berkeley, USA
C.A.J. Palmer
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom

Funding: Helmholtz Institute, Bundesministerium für Bildung und Forschung, and European Union‘s Horizon 2020 research and innovation program.
Density modulations in plasma caused by a high-intensity laser or a high charge density electron pulse can generate extreme acceleration fields. Acceleration of electrons in such fields may produce ultra-relativistic, quasi-monoenergetic, ultra-short electron bunches over distances orders of magnitudes shorter than in state-of-the-art radio-frequency accelerators. FLASHForward is such a beam-driven plasma wakefield accelerator (PWFA) project at DESY with the goal of producing, characterizing, and utilizing such beams. Temporal characterization of the acceleration process is of crucial importance for improving the stability and control in PWFA beams. While measurement of the transient field of the femtosecond bunch in a single shot is challenging, in recent years novel techniques with great promise have been developed** ***. This work discusses the plans and status of the transverse diagnostics at FLASHForward.
*A. Aschikhin et. al., NIMA , Volume 806 (11 January 2016) pp. 175-183.
**A. Buck et al., Nature Physics 7, (2011) 543.
***C. J. Zhang et al., Phys. Rev. Lett. 119 (2017) 064801.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPML040

Export •

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

WEPAF050

Simulations of 3D Charge Density Measurements for Commissioning of the PolariX-TDS

1930

SUSPF104

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

D. Marx, R.W. Aßmann, R.T.P. D'Arcy, B. Marchetti
DESY, Hamburg, Germany

The prototype of a novel X-band transverse deflection structure, the Polarizable X-band (PolariX) TDS*, is currently being prepared for installation in the FLASHForward beamline** at DESY in early 2019. This structure will have the novel feature of variable polarization of the deflecting mode, allowing bunches to be streaked at any transverse angle, rather than at just one angle as in a conventional cavity. By combining screen profiles from several streaking angles using tomographic reconstruction techniques, the full 3D charge density of a bunch can be obtained***. It is planned to perform this measurement for the first time during commissioning of the structure. In this paper, simulations of this measurement are presented and the effects of jitter are discussed.
*P Craievich et al. paper THPAL068, this conference
**A Aschikhin et al. Nucl. Instr. Meth. Phys. Res. A., vol.806, pp.175-183, 2018
***D Marx et al. J. Phys.: Conf. Ser., vol.874, p.012077, 2017

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAF050

Export •

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

THPAL068

Status of the Polarix-TDS Project

3808

P. Craievich, M. Bopp, H.-H. Braun, R. Ganter, T. Kleeb, M. Pedrozzi, E. Prat, S. Reiche, R. Zennaro
PSI, Villigen PSI, Switzerland
R.W. Aßmann, F. Christie, R.T.P. D'Arcy, U. Dorda, M. Foese, P. González Caminal, M. Hoffmann, M. Hüning, R. Jonas, O. Krebs, S. Lederer, V. Libov, B. Marchetti, D. Marx, J. Osterhoff, F. Poblotzki, M. Reukauff, H. Schlarb, S. Schreiber, G. Tews, M. Vogt, A. Wagner
DESY, Hamburg, Germany
N. Catalán Lasheras, A. Grudiev, G. McMonagle, W. Wuensch
CERN, Geneva, Switzerland

A collaboration between DESY, PSI and CERN has been established to develop and build an advanced modular X-band transverse deflection structure (TDS) system with the new feature of providing variable polarization of the deflecting force. This innovative CERN design requires very high manufacturing precision to guarantee highest azimuthal symmetry of the structure to avoid the deterioration of the polarization of the streaking field. Therefore, the high-precision tuning-free production process developed at PSI for the C-band and X-band accelerating structures will be used for the manufacturing. We summarize in this paper the status of the production of the prototype and the waveguide networks foreseen in the different facilities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL068

Export •

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