FEL2019 - List of Keywords (optics)

Paper	Title	Other Keywords	Page
WEB03	Application of Machine Learning to Beam Diagnostics	network, diagnostics, controls, target	311
	E. Fol, R. Tomás CERN, Meyrin, Switzerland J.M. Coello de Portugal PSI, Villigen PSI, Switzerland G. Franchetti GSI, Darmstadt, Germany
	Machine Learning (ML) techniques are widely used in science and industry to discover relevant information and make predictions from data. The application ranges from face recognition to High Energy Physics experiments. Recently, the application of ML has grown also in accelerator physics and in particular in the domain of diagnostics and control. The target is to provide an overview of ML techniques and to indicate beam diagnostics tasks where ML based solutions can be efficiently applied to complement or potentially surpass existing methods. Besides, a short summary of recent works will be given demonstrating the great interest for use of ML concepts in beam diagnostics and latest results of incorporating these concepts into accelerator problems, with the focus on beam optics related application.
	Slides WEB03 [5.721 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEB03
About •	paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
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WEP006	A PolariX TDS for the FLASH2 Beamline	emittance, electron, photon, FEL	328
	F. Christie, J. Rönsch-Schulenburg, M. Vogt DESY, Hamburg, Germany
	Transverse Deflecting RF-Structures (TDS) are successfully used for longitudinal diagnostic purposes at many Free-Electron Lasers (FEL) (LCLS, FLASH, EU-XFEL, FERMI). Moreover, by installing a TDS downstream of the FEL undulators and placing the measurement screen in a dispersive section, the temporal photon pulse structure can be estimated, as was demonstrated at LCLS and sFLASH. Here we describe the installation of a variable polarization X-band structure (PolariX TDS [1]) downstream of the FLASH2 undulators. The installation of such a TDS enables longitudinal phase space measurements and photon pulse reconstructions, as well as slice emittance measurements in both planes using the same cavity due to the unique variable polarization of the PolariX TDS. [1] P. Craievich et al., "Status of the PolariX-TDS Project", in Proc. IPAC’18, Vancouver, Canada (2018)
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP006
About •	paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP050	Status of Chirped Pulse Laser Shaping for the PITZ Photoinjector	laser, electron, flattop, simulation	437
	C. Koschitzki, Y. Chen, J.D. Good, M. Groß, M. Krasilnikov, G. Loisch, R. Niemczyk, F. Stephan DESY Zeuthen, Zeuthen, Germany E. Khazanov, S. Mironov IAP/RAS, Nizhny Novgorod, Russia T. Lang, L. Winkelmann DESY, Hamburg, Germany
	The beam emittance at FEL facilities like European XFEL and FLASH is dominated by the emittance sources in the electron injector. Shaping of the laser pulses that are employed to release electrons from the cathode of a photo injector, was shown in theory to allow improved beam emittance starting from the electron emission process. At the photo injector test facility at DESY in Zeuthen (PITZ) a laser system capable of controlling the temporal and spatial profile of laser pulses is being set up to demonstrate the predicted emittance reduction experimentally. The presentation will show its current capabilities to provide temporally and spatially shaped laser pulses from a pulse shaper operating at infrared (IR) wavelengths. Furthermore, results from a shape preserving conversion into fourth harmonic ultra-violet (UV), as needed for the photo emission process, will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP050
About •	paper received ※ 21 August 2019 paper accepted ※ 17 September 2019 issue date ※ 05 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP001	Steffen Hard-Edge Model for Quadrupoles with Extended Fringe-Fields at the European XFEL	quadrupole, FEL, focusing, linac	588
	N. Golubeva, V. Balandin, W. Decking, L. Fröhlich, M. Scholz DESY, Hamburg, Germany
	For modeling of linear focusing properties of quadrupole magnets the conventional rectangular model is commonly used for the design and calculations of the linear beam optics for accelerators. At the European XFEL the quadrupole magnets are described using a more accurate Steffen hard-edge model. In this paper we discuss the application of the Steffen approach for the European XFEL quadrupoles and present the examination of the model with the orbit response matrix technique.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP001
About •	paper received ※ 20 August 2019 paper accepted ※ 25 August 2019 issue date ※ 05 November 2019
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THP054	Nanosecond Pulse Enhancement in Narrow Linewidth Cavity for Steady-State Microbunching	cavity, laser, simulation, impedance	697
	Q.H. Zhou Southwest University of Science and Technology, Mianyang, Sichuan, People’s Republic of China
	Funding: The National Natural Science Foundation of China under Grant No.11875227. In steady-state microbunching (SSMB), nanosecond laser pulse with megawatt average power is required. We build up a theoretic model to enhance such pulse in a narrow linewidth (e.g. kHz level) cavity for this demand, which shows that a mode-locked mechanism in frequency domain should be considered. Simulations indicate that such pulse can be enhanced sufficiently under this condition. And we also propose some experimental schematics to realize it.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP054
About •	paper received ※ 25 August 2019 paper accepted ※ 22 October 2019 issue date ※ 05 November 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

WEB03

Application of Machine Learning to Beam Diagnostics

network, diagnostics, controls, target

311

E. Fol, R. Tomás
CERN, Meyrin, Switzerland
J.M. Coello de Portugal
PSI, Villigen PSI, Switzerland
G. Franchetti
GSI, Darmstadt, Germany

Machine Learning (ML) techniques are widely used in science and industry to discover relevant information and make predictions from data. The application ranges from face recognition to High Energy Physics experiments. Recently, the application of ML has grown also in accelerator physics and in particular in the domain of diagnostics and control. The target is to provide an overview of ML techniques and to indicate beam diagnostics tasks where ML based solutions can be efficiently applied to complement or potentially surpass existing methods. Besides, a short summary of recent works will be given demonstrating the great interest for use of ML concepts in beam diagnostics and latest results of incorporating these concepts into accelerator problems, with the focus on beam optics related application.

Slides WEB03 [5.721 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEB03

About •

paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

Export •

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

WEP006

A PolariX TDS for the FLASH2 Beamline

emittance, electron, photon, FEL

328

F. Christie, J. Rönsch-Schulenburg, M. Vogt
DESY, Hamburg, Germany

Transverse Deflecting RF-Structures (TDS) are successfully used for longitudinal diagnostic purposes at many Free-Electron Lasers (FEL) (LCLS, FLASH, EU-XFEL, FERMI). Moreover, by installing a TDS downstream of the FEL undulators and placing the measurement screen in a dispersive section, the temporal photon pulse structure can be estimated, as was demonstrated at LCLS and sFLASH. Here we describe the installation of a variable polarization X-band structure (PolariX TDS [1]) downstream of the FLASH2 undulators. The installation of such a TDS enables longitudinal phase space measurements and photon pulse reconstructions, as well as slice emittance measurements in both planes using the same cavity due to the unique variable polarization of the PolariX TDS.
[1] P. Craievich et al., "Status of the PolariX-TDS Project", in Proc. IPAC’18, Vancouver, Canada (2018)

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP006

About •

paper received ※ 20 August 2019 paper accepted ※ 27 August 2019 issue date ※ 05 November 2019

Export •

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

WEP050

Status of Chirped Pulse Laser Shaping for the PITZ Photoinjector

laser, electron, flattop, simulation

437

C. Koschitzki, Y. Chen, J.D. Good, M. Groß, M. Krasilnikov, G. Loisch, R. Niemczyk, F. Stephan
DESY Zeuthen, Zeuthen, Germany
E. Khazanov, S. Mironov
IAP/RAS, Nizhny Novgorod, Russia
T. Lang, L. Winkelmann
DESY, Hamburg, Germany

The beam emittance at FEL facilities like European XFEL and FLASH is dominated by the emittance sources in the electron injector. Shaping of the laser pulses that are employed to release electrons from the cathode of a photo injector, was shown in theory to allow improved beam emittance starting from the electron emission process. At the photo injector test facility at DESY in Zeuthen (PITZ) a laser system capable of controlling the temporal and spatial profile of laser pulses is being set up to demonstrate the predicted emittance reduction experimentally. The presentation will show its current capabilities to provide temporally and spatially shaped laser pulses from a pulse shaper operating at infrared (IR) wavelengths. Furthermore, results from a shape preserving conversion into fourth harmonic ultra-violet (UV), as needed for the photo emission process, will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-WEP050

About •

paper received ※ 21 August 2019 paper accepted ※ 17 September 2019 issue date ※ 05 November 2019

Export •

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

THP001

Steffen Hard-Edge Model for Quadrupoles with Extended Fringe-Fields at the European XFEL

quadrupole, FEL, focusing, linac

588

N. Golubeva, V. Balandin, W. Decking, L. Fröhlich, M. Scholz
DESY, Hamburg, Germany

For modeling of linear focusing properties of quadrupole magnets the conventional rectangular model is commonly used for the design and calculations of the linear beam optics for accelerators. At the European XFEL the quadrupole magnets are described using a more accurate Steffen hard-edge model. In this paper we discuss the application of the Steffen approach for the European XFEL quadrupoles and present the examination of the model with the orbit response matrix technique.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP001

About •

paper received ※ 20 August 2019 paper accepted ※ 25 August 2019 issue date ※ 05 November 2019

Export •

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

THP054

Nanosecond Pulse Enhancement in Narrow Linewidth Cavity for Steady-State Microbunching

cavity, laser, simulation, impedance

697

Q.H. Zhou
Southwest University of Science and Technology, Mianyang, Sichuan, People’s Republic of China

Funding: The National Natural Science Foundation of China under Grant No.11875227.
In steady-state microbunching (SSMB), nanosecond laser pulse with megawatt average power is required. We build up a theoretic model to enhance such pulse in a narrow linewidth (e.g. kHz level) cavity for this demand, which shows that a mode-locked mechanism in frequency domain should be considered. Simulations indicate that such pulse can be enhanced sufficiently under this condition. And we also propose some experimental schematics to realize it.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2019-THP054

About •

paper received ※ 25 August 2019 paper accepted ※ 22 October 2019 issue date ※ 05 November 2019

Export •

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