IPAC2011 - List of Authors (Nghiem, P.A.P.)

Paper

Title

Page

Dynamics of the IFMIF Very High-intensity Beam

53

P.A.P. Nghiem, R.D. Duperrier, A. Mosnier, D. Uriot
CEA/DSM/IRFU, France
N. Chauvin, O. Delferrière, W. Simeoni
CEA/IRFU, Gif-sur-Yvette, France
M. Comunian
INFN/LNL, Legnaro (PD), Italy
C. Oliver
CIEMAT, Madrid, Spain

For the purpose of material studies for future nuclear fusion reactors, the IFMIF deuteron beams present a simultaneous combination of unprecedentedly high intensity (2x125 mA CW), power (2x5 MW) and space charge. Special considerations and new concepts have been developed in order to overcome these challenges. The global strategy for beam dynamics design in the 40 MeV IFMIF accelerators is presented, stressing on the control of micro-losses, and the possibility of on-line fine tuning. The obtained results are then analysed in terms of beam halo and emittance growth.

Slides MOODB01 [3.807 MB]

MOPS025

Studies of Emittance Measurement by Quadrupole Variation for the IFMIF-EVEDA High Space Charge Beam

652

P.A.P. Nghiem, E. Counienc
CEA/DSM/IRFU, France
N. Chauvin
CEA/IRFU, Gif-sur-Yvette, France
C. Oliver
CIEMAT, Madrid, Spain

For the high-power (1 MW) beam of the IFMIF-EVEDA prototype accelerator, emittance measurements at nearly full power are only possible in a non-interceptive way. The method of quadrupole variation is explored here. Due to the high space charge regime, beam transport is strongly non-linear, and the classical matrix inversion is no more relevant. Inverse calculations using a multiparticle code is mandatory. In this paper, such emittance measurements are studied, aiming at checking its feasibility and evaluating its precision, taking into account the constraints of losses and quadrupole limitations.

MOPS026

Start-to-end Beam Dynamics Simulations for the Prototype Accelerator of the IFMIF/EVEDA Project

655

N. Chauvin
CEA/IRFU, Gif-sur-Yvette, France
M. Comunian
INFN/LNL, Legnaro (PD), Italy
O. Delferrière, R.D. Duperrier, R. Gobin, A. Mosnier, P.A.P. Nghiem, D. Uriot
CEA/DSM/IRFU, France
C. Oliver
CIEMAT, Madrid, Spain

The EVEDA (Engineering Validation and Engineering Design Activities) phase of the IFMIF (International Fusion Materials Irradiation Facility) project consists in building, testing and operating a 125 mA/9 MeV prototype accelerator in Rokkasho-Mura (Japan). Because of high beam intensity and power, the different sections of the accelerator (injector, RFQ, MEBT, Superconducting Radio-Frequency linac and HEBT) have been optimized with the twofold objective of minimizing losses along the machine and keeping a good beam quality. Extensive start-to-end multi-particles simulations have been performed to validate the prototype accelerator design. A Monte Carlo error analysis has been carried out to study the effects of misalignments and field variations. In this paper, the results of theses beam dynamics simulations, in terms of beam emittance, halo formation and beam losses, are presented.

MOPS027

Stability Charts for the IFMIF SRF-Linac

658

W. Simeoni, N. Chauvin
CEA/IRFU, Gif-sur-Yvette, France
A. Mosnier, P.A.P. Nghiem, D. Uriot
CEA/DSM/IRFU, France

Among the most recent projects, the IFMIF-EVEDA accelerators break the record of high intensity, leading to a multi-MW beam power at relatively low energy. The concern for such accelerated beams is the predominance of the self-field energy upon the beam energy. In these conditions, the space charge effect is at its maximum, which triggers different nonlinear mechanisms implying emittance growth, halo formation and sudden particle lost. In this proceeding we show the stability charts constructed for the IFMIF SRF-Linac, with which are identified the collective space charge resonances responsible of transverse-longitudinal emittance exchange and emittance growth.

Paper	Title	Page
MOODB01	Dynamics of the IFMIF Very High-intensity Beam	53
	P.A.P. Nghiem, R.D. Duperrier, A. Mosnier, D. Uriot CEA/DSM/IRFU, France N. Chauvin, O. Delferrière, W. Simeoni CEA/IRFU, Gif-sur-Yvette, France M. Comunian INFN/LNL, Legnaro (PD), Italy C. Oliver CIEMAT, Madrid, Spain
	For the purpose of material studies for future nuclear fusion reactors, the IFMIF deuteron beams present a simultaneous combination of unprecedentedly high intensity (2x125 mA CW), power (2x5 MW) and space charge. Special considerations and new concepts have been developed in order to overcome these challenges. The global strategy for beam dynamics design in the 40 MeV IFMIF accelerators is presented, stressing on the control of micro-losses, and the possibility of on-line fine tuning. The obtained results are then analysed in terms of beam halo and emittance growth.
	Slides MOODB01 [3.807 MB]

MOPS025	Studies of Emittance Measurement by Quadrupole Variation for the IFMIF-EVEDA High Space Charge Beam	652
	P.A.P. Nghiem, E. Counienc CEA/DSM/IRFU, France N. Chauvin CEA/IRFU, Gif-sur-Yvette, France C. Oliver CIEMAT, Madrid, Spain
	For the high-power (1 MW) beam of the IFMIF-EVEDA prototype accelerator, emittance measurements at nearly full power are only possible in a non-interceptive way. The method of quadrupole variation is explored here. Due to the high space charge regime, beam transport is strongly non-linear, and the classical matrix inversion is no more relevant. Inverse calculations using a multiparticle code is mandatory. In this paper, such emittance measurements are studied, aiming at checking its feasibility and evaluating its precision, taking into account the constraints of losses and quadrupole limitations.

MOPS026	Start-to-end Beam Dynamics Simulations for the Prototype Accelerator of the IFMIF/EVEDA Project	655
	N. Chauvin CEA/IRFU, Gif-sur-Yvette, France M. Comunian INFN/LNL, Legnaro (PD), Italy O. Delferrière, R.D. Duperrier, R. Gobin, A. Mosnier, P.A.P. Nghiem, D. Uriot CEA/DSM/IRFU, France C. Oliver CIEMAT, Madrid, Spain
	The EVEDA (Engineering Validation and Engineering Design Activities) phase of the IFMIF (International Fusion Materials Irradiation Facility) project consists in building, testing and operating a 125 mA/9 MeV prototype accelerator in Rokkasho-Mura (Japan). Because of high beam intensity and power, the different sections of the accelerator (injector, RFQ, MEBT, Superconducting Radio-Frequency linac and HEBT) have been optimized with the twofold objective of minimizing losses along the machine and keeping a good beam quality. Extensive start-to-end multi-particles simulations have been performed to validate the prototype accelerator design. A Monte Carlo error analysis has been carried out to study the effects of misalignments and field variations. In this paper, the results of theses beam dynamics simulations, in terms of beam emittance, halo formation and beam losses, are presented.

MOPS027	Stability Charts for the IFMIF SRF-Linac	658
	W. Simeoni, N. Chauvin CEA/IRFU, Gif-sur-Yvette, France A. Mosnier, P.A.P. Nghiem, D. Uriot CEA/DSM/IRFU, France
	Among the most recent projects, the IFMIF-EVEDA accelerators break the record of high intensity, leading to a multi-MW beam power at relatively low energy. The concern for such accelerated beams is the predominance of the self-field energy upon the beam energy. In these conditions, the space charge effect is at its maximum, which triggers different nonlinear mechanisms implying emittance growth, halo formation and sudden particle lost. In this proceeding we show the stability charts constructed for the IFMIF SRF-Linac, with which are identified the collective space charge resonances responsible of transverse-longitudinal emittance exchange and emittance growth.