IPAC2011 - List of Authors (Oliver, C.)

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.

TUPC126

Indirect Measurement of Power Deposition on the IFMIF/EVEDA Beam Dump by means of Radiation Chambers

1314

D. Rapisarda, J.M. Arroyo, B. Brañas, A. Ibarra, D. Iglesias, C. Oliver
CIEMAT, Madrid, Spain
F. Ogando
UNED, Madrid, Spain

Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230
The beam stop of the IFMIF/EVEDA accelerator will be a copper cone receiving a total power of ~1 MW, coming from 9 MeV D⁺ at 125 mA. The mechanical stresses in this beam dump come mainly from the thermal gradients generated in the cone, being therefore related with the power deposition profile. Anomalous situations such as beam misalignments or incorrect focusing can lead to variations in this profile outside the normal operation range. These variations must be detected and corrected for beam dump protection. Due to the interaction between D⁺ and the copper cone important neutron and gamma fluxes are generated around the beam dump (10¹⁰ – 10¹¹ n/cm²/s, 10¹⁰ p/cm²/s) with a spatial profile which is directly linked to the power deposition. In this work, a diagnostic based on a set of radiation chambers is proposed to measure on-line this radiation field, giving indirect information about the power deposition on the beam dump. The sensitivity of the radiation field to the power deposition profile is demonstrated and the diagnostic strategy explained, establishing the main specifications and requirements of the detectors.

WEPO014

Magnetic Design of Quadrupoles for the Medium and High Energy Beam Transport line of the LIPAC Accelerator

2424

C. Oliver, B. Brañas, A. Ibarra, I. Podadera, F. Toral
CIEMAT, Madrid, Spain

Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230.
The LIPAC accelerator will be a 9 MeV, 125 mA cw deuteron accelerator which will verify the validity of the design of the future IFMIF accelerator. A Medium Energy Beam Transport line (MEBT) is necessary to handle the high current beam from the RFQ to the Superconducting RF accelerating cavities (SRF) whereas a High Energy Beam Transport line (HEBT) is used to match the beam from the SRF to the beam dump. The high space charge and beam power determine the beam dynamics in both transport lines. As a consequence, magnets with strong fields in a reduced space are required. Along the transport beamlines, there are different types of quadrupoles with steerers and a dipole. Special care is devoted to maximize the integrated fields in the available space. Both 2-D and 3-D magnetic calculations are used to optimize coil configurations. Magnetic performance and cost, both of magnet and power supply, have been taken into account for final choice. In this paper, the design of the resistive quadrupoles of the MEBT and HEBT of the LIPAC accelerator is presented.

WEPS058

The Medium Energy Beam Transport Line (MEBT) of IFMIF/EVEDA LIPAc

2628

I. Podadera, J.C. Calvo, J.M. Carmona, A. Ibarra, D. Iglesias, A. Lara, C. Oliver, F. Toral
CIEMAT, Madrid, Spain

Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230.
The IFMIF-EVEDA Linear IFMIF Prototype Accelerator (LIPAc)will be a 9 MeV, 125 mA CW deuteron accelerator which aims to validate the technology that will be used in the future IFMIF accelerator. The acceleration of the beam will be carried out in two stages. An RFQ will increase the energy up to 5 MeV before a Superconducting RF (SRF) linac made of a chain of eight Half Wave Resonators bring the particles to the final energy. Between both stages, a Medium Energy Beam Transport line (MEBT) is in charge of transporting and matching the beam between the RFQ and the SRF. The transverse focusing of the beam is controlled by five quadrupole magnets with integrated steerers, grouped in one triplet and one doublet. Two buncher cavities surrounding the doublet handle the longitudinal dynamics. Two movable collimators are also included to purify the beam optics coming out the RFQ and avoid losses in the SRF. From the inputs of the beam dynamics group, CIEMAT is in charge of designing, manufacturing and integrating all the components of the beamline. In this contribution, the MEBT subsystem will be described and the main objectives and issues for each component will be discussed.

THPS059

Thermo-mechanical Design of Particle-stopping Devices at the High Energy Beamline Sections of the IFMIF/EVEDA Accelerator

3562

D. Iglesias, F. Arranz, B. Brañas, J.M. Carmona, N. Casal, A. Ibarra, C. Oliver, M. Parro, I. Podadera, D. Rapisarda
CIEMAT, Madrid, Spain

Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230.
The IFMIF/EVEDA linear accelerator is a 9 MeV, D⁺ prototype for the validation of the 40 MeV final IFMIF design. The high intensity, 125 mA CW, high power beam (1.125 MW) produces an extremely high thermal load in all the elements intercepting the ions. Independently of the final purpose of each device, if its working conditions imply stopping a non-negligible amount of particles, the associated thermal solicitation greatly determines the design constraints. The present work will summarize a thermo-mechanical design workflow that can be applied to any beam facing element of high current accelerators and its application in beam dump, scrappers and slits design. This approach is based on analysis experiences at the IFMIF/EVEDA project and, while taking into account the particularities of each device, uses the same tools and parameter evaluation criteria for all of them. It has been applied successfully to recent designs, effectively reducing the number of iterations before achieving a valid thermo-mechanical behavior. Results of each design and the concrete advantages of this approach will be detailed.

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.

TUPC126	Indirect Measurement of Power Deposition on the IFMIF/EVEDA Beam Dump by means of Radiation Chambers	1314
	D. Rapisarda, J.M. Arroyo, B. Brañas, A. Ibarra, D. Iglesias, C. Oliver CIEMAT, Madrid, Spain F. Ogando UNED, Madrid, Spain
	Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230 The beam stop of the IFMIF/EVEDA accelerator will be a copper cone receiving a total power of ~1 MW, coming from 9 MeV D⁺ at 125 mA. The mechanical stresses in this beam dump come mainly from the thermal gradients generated in the cone, being therefore related with the power deposition profile. Anomalous situations such as beam misalignments or incorrect focusing can lead to variations in this profile outside the normal operation range. These variations must be detected and corrected for beam dump protection. Due to the interaction between D⁺ and the copper cone important neutron and gamma fluxes are generated around the beam dump (10¹⁰ – 10¹¹ n/cm²/s, 10¹⁰ p/cm²/s) with a spatial profile which is directly linked to the power deposition. In this work, a diagnostic based on a set of radiation chambers is proposed to measure on-line this radiation field, giving indirect information about the power deposition on the beam dump. The sensitivity of the radiation field to the power deposition profile is demonstrated and the diagnostic strategy explained, establishing the main specifications and requirements of the detectors.

WEPO014	Magnetic Design of Quadrupoles for the Medium and High Energy Beam Transport line of the LIPAC Accelerator	2424
	C. Oliver, B. Brañas, A. Ibarra, I. Podadera, F. Toral CIEMAT, Madrid, Spain
	Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230. The LIPAC accelerator will be a 9 MeV, 125 mA cw deuteron accelerator which will verify the validity of the design of the future IFMIF accelerator. A Medium Energy Beam Transport line (MEBT) is necessary to handle the high current beam from the RFQ to the Superconducting RF accelerating cavities (SRF) whereas a High Energy Beam Transport line (HEBT) is used to match the beam from the SRF to the beam dump. The high space charge and beam power determine the beam dynamics in both transport lines. As a consequence, magnets with strong fields in a reduced space are required. Along the transport beamlines, there are different types of quadrupoles with steerers and a dipole. Special care is devoted to maximize the integrated fields in the available space. Both 2-D and 3-D magnetic calculations are used to optimize coil configurations. Magnetic performance and cost, both of magnet and power supply, have been taken into account for final choice. In this paper, the design of the resistive quadrupoles of the MEBT and HEBT of the LIPAC accelerator is presented.

WEPS058	The Medium Energy Beam Transport Line (MEBT) of IFMIF/EVEDA LIPAc	2628
	I. Podadera, J.C. Calvo, J.M. Carmona, A. Ibarra, D. Iglesias, A. Lara, C. Oliver, F. Toral CIEMAT, Madrid, Spain
	Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230. The IFMIF-EVEDA Linear IFMIF Prototype Accelerator (LIPAc)will be a 9 MeV, 125 mA CW deuteron accelerator which aims to validate the technology that will be used in the future IFMIF accelerator. The acceleration of the beam will be carried out in two stages. An RFQ will increase the energy up to 5 MeV before a Superconducting RF (SRF) linac made of a chain of eight Half Wave Resonators bring the particles to the final energy. Between both stages, a Medium Energy Beam Transport line (MEBT) is in charge of transporting and matching the beam between the RFQ and the SRF. The transverse focusing of the beam is controlled by five quadrupole magnets with integrated steerers, grouped in one triplet and one doublet. Two buncher cavities surrounding the doublet handle the longitudinal dynamics. Two movable collimators are also included to purify the beam optics coming out the RFQ and avoid losses in the SRF. From the inputs of the beam dynamics group, CIEMAT is in charge of designing, manufacturing and integrating all the components of the beamline. In this contribution, the MEBT subsystem will be described and the main objectives and issues for each component will be discussed.

THPS059	Thermo-mechanical Design of Particle-stopping Devices at the High Energy Beamline Sections of the IFMIF/EVEDA Accelerator	3562
	D. Iglesias, F. Arranz, B. Brañas, J.M. Carmona, N. Casal, A. Ibarra, C. Oliver, M. Parro, I. Podadera, D. Rapisarda CIEMAT, Madrid, Spain
	Funding: Work partially supported by Spanish Ministry of Science and Innovation under project AIC10-A-000441 and ENE2009-11230. The IFMIF/EVEDA linear accelerator is a 9 MeV, D⁺ prototype for the validation of the 40 MeV final IFMIF design. The high intensity, 125 mA CW, high power beam (1.125 MW) produces an extremely high thermal load in all the elements intercepting the ions. Independently of the final purpose of each device, if its working conditions imply stopping a non-negligible amount of particles, the associated thermal solicitation greatly determines the design constraints. The present work will summarize a thermo-mechanical design workflow that can be applied to any beam facing element of high current accelerators and its application in beam dump, scrappers and slits design. This approach is based on analysis experiences at the IFMIF/EVEDA project and, while taking into account the particularities of each device, uses the same tools and parameter evaluation criteria for all of them. It has been applied successfully to recent designs, effectively reducing the number of iterations before achieving a valid thermo-mechanical behavior. Results of each design and the concrete advantages of this approach will be detailed.