FEL2014 - List of Keywords (dipole)

Paper	Title	Other Keywords	Page
MOP032	PAL-XFEL Magnet Power Supply System	controls, power-supply, quadrupole, status	87
	S.-H. Jeong, H.-S. Kang, D.E. Kim, I.S. Ko, H.-G. Lee, S.B. Lee, B.G. Oh, K.-H. Park, H.S. Suh, Y.G. Young-Gyu PAL, Pohang, Kyungbuk, Republic of Korea
	This paper presents an overview of the magnet power supply(MPS) for the PAL-XFEL. The number of total MPS is 628 and they will be installed along the accelerator and the undulator sections. The power capacity of the MPS was ranging from about 1 A to 300 A. These MPSs were required to meet the high stability that was subjected from the beam dynamics specifications. This paper described the overall MPS requirements, MPS assembling, test process, control scheme, installation plan and so on.

MOP033	Design, Fabrication, and Performance Tests of Dipole and Quadrupole Magnets for PAL-XFEL	quadrupole, multipole, undulator, optics	90
	H.S. Suh, M.-H. Cho, S.-H. Jeong, Y.-G. Jung, H.-S. Kang, D.E. Kim, I.S. Ko, H.-G. Lee, S.B. Lee, B.G. Oh, K.-H. Park PAL, Pohang, Kyungbuk, Republic of Korea
	PAL-XFEL is now being constructed in Pohang, Korea. This facility will consist of a 10 GeV linac and five undulator beamlines. As the first phase we will construct one hard X-ray and one soft X-ray beamlines which require 7 different families of dipole magnets, and 11 families of quadrupole magnets. We are designing these magnets with considering the efficient manufacturing and the proper power supplies. In this presentation, we describe the design features of the magnets, the manufacturing, and the thermal analysis with the test results.

MOP039	High Stability Resonant Kicker Development for the SwissFEL Switch Yard	kicker, operation, electron, linac	103
	M. Paraliev, H.-H. Braun, S. Dordevic, C.H. Gough PSI, Villigen PSI, Switzerland
	The SwissFEL is a linac-based X-ray free electron laser facility under construction at the Paul Scherrer Institute. The facility will provide femtosecond, high brightness X-ray pulses for fundamental and applied science research. To increase facility efficiency, a double bunch operation is planned to serve simultaneously two experimental stations at the full linac repetition rate. The main linac will accelerate two electron bunches spaced 28 ns apart and a fast and stable deflecting system will be used to separate the two bunches into two different undulator lines. The deflecting system uses a novel concept based on resonant kicker magnets. A prototype kicker magnet and its control system were designed and built. Since stability is crucial, the stability performance of the prototype was studied. The peak to peak amplitude stability of ±11 ppm (3.5 ppm rms) was achieved, which is well within the FEL tolerance of ±80 ppm. The layout of the deflecting system and the key design parameters are also presented.

MOP087	Upgrade Plans for the Short-pulse Facility at DELTA	laser, electron, undulator, radiation	255
	S. Hilbrich, H. Huck, M. Huck, M. Höner, S. Khan, C. Mai, A. Meyer auf der Heide, R. Molo, H. Rast, P. Ungelenk DELTA, Dortmund, Germany
	Funding: Work supported by DFG, BMBF, FZ Jülich, and by the Land NRW. DELTA is a 1.5-GeV synchrotron light source operated by the TU Dortmund University with a short-pulse facility based on Coherent Harmonic Generation (CHG) * to produce radiation with wavelengths in the VUV regime. Even shorter wavelengths can be generated by an upgrade based on the Echo-Enabled Harmonic Generation (EEHG) technique ** which requires additional magnetic chicanes and undulators. A new storage ring lattice provides enough free space for an EEHG setup and additionally for a femtoslicing undulator. Besides the new optics, first simulation results of EEHG will be presented. * S. Khan et al., Sync. Rad. News 26, 3 (2013). ** G. Stupakov, Phys. Rev. Lett. 102, 074801 (2009).

MOP095	HGHG AND EEHG MICROBUNCHES WITH CSR AND LSC	simulation, electron, FEL, radiation	275
	K.E. Hacker DELTA, Dortmund, Germany
	Funding: Work supported by BMBF (contract 05K13PE3) and DESY Longitudinal space charge (LSC) forces in a drift and coherent synchrotron radiation (CSR) in a chicane are relevant for high gain harmonic generation (HGHG) and echo enabled harmonic generation (EEHG) seeding designs. These factors determine whether or not the modulator can be located significantly upstream of the radiator. The benefits and dangers of having a drift in between the radiator and the modulator are investigated and a measurement of the LSC enabled reduction of the energy spread of a seeded beam is presented.

THP023	Simulation of Alpha Magnet Elements in Dipole-only Tracking Codes	simulation, electron, beam-transport, coupling	735
	J.W. Lewellen, F.L. Krawczyk LANL, Los Alamos, New Mexico, USA
	Alpha magnets are used in a variety of ion-beam and low-energy (< 5 MeV) electron-beam transport systems as both “switchyard” elements and as bunch compressors. A unique feature of the alpha-magnet is its natively achromatic transport. Particles of different energies, injected at a specific location and angle, will exit at the same location and (symmetry-reflected) angle but with a different time-of-flight. Despite the general usefulness of alpha magnets in low-energy beam transport and compression schemes, few simulation codes support them as native elements. The (arguably) most-common codes used for injector design, PARMELA, ASTRA and GPT (listed in order of their release) do not support alpha magnets natively, but do support modeling of space-charge-dominated beams through dipole magnets. As a result, the most commonly used injector design codes are unable to incorporate one of the most useful and interesting beam transport devices. We present a method for simulating an alpha magnet in a tracking code using dipole elements. As elegant supports both dipoles and alpha magnets, it is used to provide a basic check of the approximation and a means of estimating the induced errors.

THP026	Design Study of LCLS Chirp-Control with a Corrugated Structure	wakefield, emittance, simulation, quadrupole	748
	Z. Zhang, K.L.F. Bane, Y. Ding, Z. Huang, R.H. Iverson, T.J. Maxwell, G.V. Stupakov, L. Wang SLAC, Menlo Park, California, USA P. Frigola, M.A. Harrison, M. Ruelas RadiaBeam, Santa Monica, California, USA
	The purpose of this paper is to investigate the use of flat metallic plates with small corrugations as a passive dechirper, studying its effects on beam dynamics. Similar systems have been tested in Pohang and Brookhaven at relatively low energies (~100 MeV) and with relatively long bunches (>1ps) [,]. Four meters of such a structure are being machined by Radiabeam Systems for use in the LCLS with a high energy and femtosecond electron beam. In this paper we use a field matching program to obtain the longitudinal and transverse wakes for the purpose of the LCLS dechirper design. In addition, we fit the longitudinal wake to simple functions, so that one can obtain the wake without resorting to the field matching program. Since the transverse wakes–both dipole and quadrupole wakes–are strong, we include beam dynamics simulations to find the tolerances for injection jitter and misalignment in the LCLS. P. Emma, et al. PRL 112, 034801 ** M. Harrison, et al., NaPAc 2013, Pasadena, USA

THP035	Relativistic Effects in Micro-bunching	bunching, electron, plasma, space-charge	790
	V. Litvinenko Stony Brook University, Stony Brook, USA G. Wang BNL, Upton, Long Island, New York, USA
	In this paper we present our theoretical studies of limits on bunching using magnetic systems. We discuss the connection of this limit with plasma oscillations in electron beams and present simple formulae for an additional limit of micro-bunching amplification.

THC03	Suppression of the CSR-induced Emittance Growth in Achromats using Two-dimensional point-kick Analysis	emittance, simulation, optics, linear-collider	976
	Y. Jiao, X. Cui, X.Y. Huang, G. Xu IHEP, Beijing, People's Republic of China
	Coherent synchrotron radiation (CSR) effect causes transverse emittance dilution in high-brightness light sources and linear colliders. Suppression of the emittance growth induced by CSR is essential and critical to preserve the beam quality and to help improve the machine performance. To evaluate the CSR effect analytically, we propose a novel method, named “two-dimensional point-kick analysis”. In this method, the CSR-induced emittance growth in an n-dipole achromat can be evaluated with the analysis of only the motion of particle in (x, x') two-dimensional plane with n-point kicks, which can be, to a large extent, counted separately. To demonstrate the effectiveness of this method, the CSR effect in a two-diople achromat and a symmetric TBA is studied, and generic conditions of suppressing the CSR-induced emittance growth, which are independent of concrete element parameters and are robust against the variation of initial beam distribution, are found. These conditions are verified with the ELEGANT simulations and can be rather easily applied to real machines.
	Slides THC03 [1.941 MB]

Paper

Title

Other Keywords

Page

MOP032

PAL-XFEL Magnet Power Supply System

controls, power-supply, quadrupole, status

87

S.-H. Jeong, H.-S. Kang, D.E. Kim, I.S. Ko, H.-G. Lee, S.B. Lee, B.G. Oh, K.-H. Park, H.S. Suh, Y.G. Young-Gyu
PAL, Pohang, Kyungbuk, Republic of Korea

This paper presents an overview of the magnet power supply(MPS) for the PAL-XFEL. The number of total MPS is 628 and they will be installed along the accelerator and the undulator sections. The power capacity of the MPS was ranging from about 1 A to 300 A. These MPSs were required to meet the high stability that was subjected from the beam dynamics specifications. This paper described the overall MPS requirements, MPS assembling, test process, control scheme, installation plan and so on.

MOP033

Design, Fabrication, and Performance Tests of Dipole and Quadrupole Magnets for PAL-XFEL

quadrupole, multipole, undulator, optics

90

H.S. Suh, M.-H. Cho, S.-H. Jeong, Y.-G. Jung, H.-S. Kang, D.E. Kim, I.S. Ko, H.-G. Lee, S.B. Lee, B.G. Oh, K.-H. Park
PAL, Pohang, Kyungbuk, Republic of Korea

PAL-XFEL is now being constructed in Pohang, Korea. This facility will consist of a 10 GeV linac and five undulator beamlines. As the first phase we will construct one hard X-ray and one soft X-ray beamlines which require 7 different families of dipole magnets, and 11 families of quadrupole magnets. We are designing these magnets with considering the efficient manufacturing and the proper power supplies. In this presentation, we describe the design features of the magnets, the manufacturing, and the thermal analysis with the test results.

MOP039

High Stability Resonant Kicker Development for the SwissFEL Switch Yard

kicker, operation, electron, linac

103

M. Paraliev, H.-H. Braun, S. Dordevic, C.H. Gough
PSI, Villigen PSI, Switzerland

The SwissFEL is a linac-based X-ray free electron laser facility under construction at the Paul Scherrer Institute. The facility will provide femtosecond, high brightness X-ray pulses for fundamental and applied science research. To increase facility efficiency, a double bunch operation is planned to serve simultaneously two experimental stations at the full linac repetition rate. The main linac will accelerate two electron bunches spaced 28 ns apart and a fast and stable deflecting system will be used to separate the two bunches into two different undulator lines. The deflecting system uses a novel concept based on resonant kicker magnets. A prototype kicker magnet and its control system were designed and built. Since stability is crucial, the stability performance of the prototype was studied. The peak to peak amplitude stability of ±11 ppm (3.5 ppm rms) was achieved, which is well within the FEL tolerance of ±80 ppm. The layout of the deflecting system and the key design parameters are also presented.

MOP087

Upgrade Plans for the Short-pulse Facility at DELTA

laser, electron, undulator, radiation

255

S. Hilbrich, H. Huck, M. Huck, M. Höner, S. Khan, C. Mai, A. Meyer auf der Heide, R. Molo, H. Rast, P. Ungelenk
DELTA, Dortmund, Germany

Funding: Work supported by DFG, BMBF, FZ Jülich, and by the Land NRW.
DELTA is a 1.5-GeV synchrotron light source operated by the TU Dortmund University with a short-pulse facility based on Coherent Harmonic Generation (CHG) * to produce radiation with wavelengths in the VUV regime. Even shorter wavelengths can be generated by an upgrade based on the Echo-Enabled Harmonic Generation (EEHG) technique ** which requires additional magnetic chicanes and undulators. A new storage ring lattice provides enough free space for an EEHG setup and additionally for a femtoslicing undulator. Besides the new optics, first simulation results of EEHG will be presented.
* S. Khan et al., Sync. Rad. News 26, 3 (2013).
** G. Stupakov, Phys. Rev. Lett. 102, 074801 (2009).

MOP095

HGHG AND EEHG MICROBUNCHES WITH CSR AND LSC

simulation, electron, FEL, radiation

275

K.E. Hacker
DELTA, Dortmund, Germany

Funding: Work supported by BMBF (contract 05K13PE3) and DESY
Longitudinal space charge (LSC) forces in a drift and coherent synchrotron radiation (CSR) in a chicane are relevant for high gain harmonic generation (HGHG) and echo enabled harmonic generation (EEHG) seeding designs. These factors determine whether or not the modulator can be located significantly upstream of the radiator. The benefits and dangers of having a drift in between the radiator and the modulator are investigated and a measurement of the LSC enabled reduction of the energy spread of a seeded beam is presented.

THP023

Simulation of Alpha Magnet Elements in Dipole-only Tracking Codes

simulation, electron, beam-transport, coupling

735

J.W. Lewellen, F.L. Krawczyk
LANL, Los Alamos, New Mexico, USA

Alpha magnets are used in a variety of ion-beam and low-energy (< 5 MeV) electron-beam transport systems as both “switchyard” elements and as bunch compressors. A unique feature of the alpha-magnet is its natively achromatic transport. Particles of different energies, injected at a specific location and angle, will exit at the same location and (symmetry-reflected) angle but with a different time-of-flight. Despite the general usefulness of alpha magnets in low-energy beam transport and compression schemes, few simulation codes support them as native elements. The (arguably) most-common codes used for injector design, PARMELA, ASTRA and GPT (listed in order of their release) do not support alpha magnets natively, but do support modeling of space-charge-dominated beams through dipole magnets. As a result, the most commonly used injector design codes are unable to incorporate one of the most useful and interesting beam transport devices. We present a method for simulating an alpha magnet in a tracking code using dipole elements. As elegant supports both dipoles and alpha magnets, it is used to provide a basic check of the approximation and a means of estimating the induced errors.

THP026

Design Study of LCLS Chirp-Control with a Corrugated Structure

wakefield, emittance, simulation, quadrupole

748

Z. Zhang, K.L.F. Bane, Y. Ding, Z. Huang, R.H. Iverson, T.J. Maxwell, G.V. Stupakov, L. Wang
SLAC, Menlo Park, California, USA
P. Frigola, M.A. Harrison, M. Ruelas
RadiaBeam, Santa Monica, California, USA

The purpose of this paper is to investigate the use of flat metallic plates with small corrugations as a passive dechirper, studying its effects on beam dynamics. Similar systems have been tested in Pohang and Brookhaven at relatively low energies (~100 MeV) and with relatively long bunches (>1ps) [*,**]. Four meters of such a structure are being machined by Radiabeam Systems for use in the LCLS with a high energy and femtosecond electron beam. In this paper we use a field matching program to obtain the longitudinal and transverse wakes for the purpose of the LCLS dechirper design. In addition, we fit the longitudinal wake to simple functions, so that one can obtain the wake without resorting to the field matching program. Since the transverse wakes–both dipole and quadrupole wakes–are strong, we include beam dynamics simulations to find the tolerances for injection jitter and misalignment in the LCLS.
* P. Emma, et al. PRL 112, 034801
** M. Harrison, et al., NaPAc 2013, Pasadena, USA

THP035

Relativistic Effects in Micro-bunching

bunching, electron, plasma, space-charge

790

V. Litvinenko
Stony Brook University, Stony Brook, USA
G. Wang
BNL, Upton, Long Island, New York, USA

In this paper we present our theoretical studies of limits on bunching using magnetic systems. We discuss the connection of this limit with plasma oscillations in electron beams and present simple formulae for an additional limit of micro-bunching amplification.

THC03

Suppression of the CSR-induced Emittance Growth in Achromats using Two-dimensional point-kick Analysis

emittance, simulation, optics, linear-collider

976

Y. Jiao, X. Cui, X.Y. Huang, G. Xu
IHEP, Beijing, People's Republic of China

Coherent synchrotron radiation (CSR) effect causes transverse emittance dilution in high-brightness light sources and linear colliders. Suppression of the emittance growth induced by CSR is essential and critical to preserve the beam quality and to help improve the machine performance. To evaluate the CSR effect analytically, we propose a novel method, named “two-dimensional point-kick analysis”. In this method, the CSR-induced emittance growth in an n-dipole achromat can be evaluated with the analysis of only the motion of particle in (x, x') two-dimensional plane with n-point kicks, which can be, to a large extent, counted separately. To demonstrate the effectiveness of this method, the CSR effect in a two-diople achromat and a symmetric TBA is studied, and generic conditions of suppressing the CSR-induced emittance growth, which are independent of concrete element parameters and are robust against the variation of initial beam distribution, are found. These conditions are verified with the ELEGANT simulations and can be rather easily applied to real machines.

Slides THC03 [1.941 MB]