Beam dynamics studies in SPIRAL II LINAC

ACCInternational audienceThe proposed LINAG driver for the SPIRAL 2 project aims to accelerate a 5-mA D+ beam up to 20 A.MeV and 1-mA beam for q/A=1/3 up to 14.5 A.MeV. It is acontinuous wave regime (cw), designed for maximum efficiency in the transmission of intense beams. It consists of an injector (two ECR sources + a Radio Frequency Quadrupole) followed by a superconducting section based on an array of independently phased cavities. This paper presents beams dynamics studies associated to the LINAG driver. End-to-end simulations (low-energy beam lines, RFQ, medium-energy beam line, SC linac) are shown

High intensity linac driver for the SPIRAL-2 project : Design of superconducting 88 MHz quarter wave resonators (beta 0.12), power couplers and cryomodules

ACCInternational audienceA Superconducting Linac Driver, delivering deuterons with energy up to 40 MeV (5 mA) and heavy ions with energy of 14.5 MeV/u (1 mA ), is proposed for the Spiral-2 radioactive beams facility. For the high energy section of the linac, a superconducting 88 MHz Quarter Wave Resonator (beta 0.12) has been designed and the optimisation of RF and mechanical performances will be presented. Based on the present state-of-art of the Superconducting RF technology, maximum electric surface field of 40 MV/m and magnetic surface field of 80 mT, have been adopted which should allow to reach an accelerating field of 7 MV/m (energy gain 3 MeV per resonator). A first complete prototype is under construction. The high intensity deuteron beam specifications have imposed the design of an original power coupler (maximum power 20 KW). The RF, mechanical, and thermal characteristics will be presented. The design of the cryomodule for this high energy section, integrating two QWR with its associated equipments (couplers, tuners, helium tanks), will be presented

Lateral Damping in a Magnet-High TcT_{\rm c} SC System

The properties shown by a magnet levitating above a high $T_{\rm c}$ superconductor pellet can lead to use them in magnetic bearings or other applications such as coupling devices or dampers. The levitation properties and the static stability are well demonstrated but it is not clear if their damping properties are sufficient for applications to avoid any active damping device. The work presented here studies the damping of the oscillations of a magnet above a superconducting pellet, in a pendulum device where displacements and forces are simultaneously measured. Magnet and superconducting pellet dimensions are of the same order. The pulsation of the harmonic motion is governed by the static lateral forces but the damping seems to be dependent on the initial amplitudes. In our configuration, even for the first oscillations, the damping is less efficient than with copper at 77 K, and the small oscillations are quite undamped.Les propriétés de lévitation entre un aimant permanent et un supraconducteur massif à haute température critique permettent d'envisager leur utilisation dans des paliers magnétiques ou dans d'autres applications (coupleurs, amortisseurs). Si leurs propriétés de lévitation et de stabilité statique sont démontrées, une des clés de leur application est leur stabilité dynamique, qui doit permettre de réaliser des dispositifs entièrement passifs performants. Ce travail présente une étude de l'amortissement à l'aide d'un dispositif permettant de mesurer en même temps les oscillations et les forces entre un aimant vibrant librement au-dessus d'une pastille supraconductrice, les deux éléments ayant des tailles analogues. La pulsation du mouvement harmonique amorti vérifie bien un comportement dans lequel les forces latérales modifient la pulsation propre, les propriétés d'amortissement paraissent non linéaires et dépendent de l'amplitude des oscillations. Dans notre configuration, même en prenant les premières oscillations, l'amortissement est moins performant que celui que l'on obtient avec du cuivre à la même température, et les petites oscillations sont peu amorties

steering effect simulations

study of the vertical steering effect of QWR resonator

HEBT lines for the SPIRAL2 facility

International audienceIThe SPIRAL2 facility at GANIL-Caen is now in its construction phase, with a project group including the participation of many French laboratories (CNRS, CEA) and international partners. The SPIRAL2 facility will be able to produce various accelerated beams at high intensities: 40 MeV Deuterons, 33 MeV Protons with intensity until 5mA and heavy ions with q/A=1/3 up to 14.5MeV/u until 1mA current. We will present the status of the beam dynamics studies recently performed for the high energy beam transport lines of the facility. Various studies were performed on beamdump concerning beam dynamics, safety and thermo-mechanicals aspects. New experimental areas using stable beams and the cave dedicated to radioactive ion production will be presented according the scientific program

High intensity driver accelerators for EURISOL

This paper describes briefly the result of the work done by the Driver Accelerator Task Group of the EURISOL RTD project. Accelerator experts from the laboratories participating in this study, namely CEA-Saclay, CERN, GANIL, INFN-Legnaro, IPN-Orsay, have elaborated different technical solutions during the period 2000-2001, following the recommendations for specifications of the EURISOL Steering committee. The main conclusion of the study is that the EURISOL baseline driver accelerator should be a 1-GeV, 5-MW CW proton facility, with a possible upgrade to 2 GeV. A cheaper "back-up" solution, based on a high-intensity electron driver for photofission, is also discussed

FIRST A/Q=3 BEAMS OF PHOENIX V2 ON THE HEAVY IONS LOW ENERGY BEAM TRANSPORT LINE OF SPIRAL2

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Reliability and fault-tolerance strategy in the MYRRHA superconducting linac

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