STFC/RAL, Chilton, Didcot, Oxon
EMMA is the world's first non-scaling fixed field alternating gradient accelerator and is being constructed at the STFC Daresbury Laboratory. Experience from the initial commissioning phases (from early 2010) will be reported and lessons for future machines of a similar type will be discussed. The present experimental status and future plans will also be reported.
KEK, Ibaraki
BNL, Upton, Long Island, New York
An RF system using Magnetic Alloy is considered as an option to study the beam dynamics of a linear non-scaling FFAG. Such an FFAG may have many resonances, which affect the beam more when the beam crosses them slowly. The RF system aims at ordinary RF bucket acceleration with an RF frequency sweep of 3 % in 100 turns. The cavity has only 10 cm length to fit in a short straight section. The required RF voltage is 100 kV per turn and each of the three cavities is designed to generate 50 kV.
STFC/RAL, Chilton, Didcot, Oxon
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
BNL, Upton, Long Island, New York
STFC/DL, Daresbury, Warrington, Cheshire
UBC & TRIUMF, Vancouver, British Columbia
Fermilab, Batavia
Brunel University, Middlesex
CERN, Geneva
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
TRIUMF, Vancouver
CEA, Gif-sur-Yvette
Imperial College of Science and Technology, Department of Physics, London
JAI, Oxford
The Electron Model for Many Applications (EMMA) will be the World's first non-scaling FFAG and is under construction at the STFC Daresbury Laboratory in the UK. Construction is due for completion in March 2010 and will be followed by commissioning with beam and a detailed experimental programme to study the functioning of this type of accelerator. This paper will give an overview of the motivation for the project and describe the EMMA design and hardware. The first results from commissioning will be presented in a separate paper.
UBC & TRIUMF, Vancouver, British Columbia
TRIUMF, Vancouver
This paper describes tracking studies of non-scaling (NS) FFAGs using cyclotron codes in place of the more conventional lumped-element synchrotron codes. The equilibrium orbit code CYCLOPS determines orbits, tunes and period at fixed energies, while the general orbit code GOBLIN tracks a representative bunch of particles through the acceleration process. Results will be presented for the EMMA linear NS-FFAG under construction at Daresbury (10-20 MeV electrons), and for two non-linear NS-FFAG designs: Rees's isochronous IFFAG (8-20 GeV muons) and Johnstone's design for ADSR (250-1000 MeV protons). Our results are compared with those obtained using lumped-element codes. In the case of EMMA, results are presented for both the measured and design fields.
CEA, Gif-sur-Yvette
Brunel University, Middlesex
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
JAI, Oxford
The Electron Model for Many Applications FFAG (EMMA) has been the object of extensive beam dynamics simulations during its design and construction phases, using the ray-tracing code Zgoubi, which has been retained as the on-line simulation engine. On the other hand EMMA commissioning requires further advanced beam dynamics studies as well as on-line and off-line simulations. This contribution reports on some aspects of the studies so performed during the last months using Zgoubi.
CEA, Gif-sur-Yvette
BNL, Upton, Long Island, New York
Brunel University, Middlesex
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
UMAN, Manchester
The EMMA (Electron Model for Many Applications) FFAG experiment at Daresbury will involve on-line modeling (a ‘‘Virtual EMMA'') based on stepwise ray-tracing methods. Various aspects of the code of concern and of its interfacing to real world - machine and users - are addressed.
IKP, Mainz
Siemens AG, Erlangen
The university of Mainz institute for nuclear physics is operating the microtron cascade MAMI (Mainzer Mikrotron) since the late 1970ies. The microtron delivers a cw electron beam to users of the hadron physics community. The recent, fourth stage MAMI-C having a design energy of 1.5 GeV is operated since 2006*. This article deals with the recent developments and operational experiences of MAMI-C, as well as with the energy upgardes to 1.56 GeV** and as final step towards 1.6 GeV. The final increase of beam energy was due to user demands, since it is expected to raise the event rate of the eta prime production by an order of magnitude.
* A.Jankowiak, et al., EPAC08, Genoa, Italy, p.51 (MOZCM01)
** A. Jankowiak, et al., PAC09, Vancouver, Canada (WE6PFP111)
USTC/NSRL, Hefei, Anhui
Fixed-Field Alternating Gradient (FFAG) accelerator accelerates in smaller costs heavy-ion with higher beam current than conventional circular accelerator, which could be more useful for the study of radioactive material. In this paper, the periodic focusing structure model of a Helium ion FFAG with a few MeV energy, which is contributed to study the impact of Helium embitterment on fusion reactor envelope material is proposed. A large-aperture magnet for Helium ion FFAG synchrotron is designed by using a 3D magnetic field simulation code OPERA-3D. The linear and nonlinear beam dynamics is studied through tracking the particle in the magnetic field generated by OPERA-3D.
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
JAI, Oxford
EMMA - the Electron Model of Many Applications - is to be built at the STFC Daresbury Laboratory in the UK and will be the first non-scaling FFAG ever constructed. The purpose of EMMA is to study beam dynamics in such an accelerator. The EMMA orbit correction scheme must deal with two characteristics of a non-scaling FFAG: i.e. the lack of a well defined reference orbit and the variation with momentum of the phase advance between lattice elements. In this study we present a novel orbit correction scheme that avoids the former problem by instead aiming to maximise both the symmetry of the orbit and the physical aperture of the beam. The latter problem is dealt with by optimising the corrector strengths over the energy range.
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
STFC/DL, Daresbury, Warrington, Cheshire
Cockcroft Institute, Warrington, Cheshire
STFC/RAL/ASTeC, Chilton, Didcot, Oxon
The first results from commissioning EMMA - the Electron Model of Many Applications- are summarised in this paper. EMMA is a 10 to 20 MeV electron ring designed to test our understanding of beam dynamics in a relativistic linear non-scaling fixed field alternating gradient accelerator (FFAG). EMMA will be the world's first non-scaling FFAG and the paper will outline the characteristics of the beam injected in to the accelerator as well as summarising the results of the extensive EMMA systems commissioning. The paper will report on the results of simulations of this commissioning and on the progress made with beam commissioning.
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
Brunel University, Middlesex
Described in the paper are systematic procedures to inject and keep the beam on the reference trajectory for a fixed energy, as applied to the EMMA non scaling FFAG accelerator. The notion of accelerated orbits in FFAG accelerators has been introduced and some of their properties have been studies in detail.
UMAN, Manchester
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
EMMA (Electron Model with Many Applications) is the first proof-of-principle non-scaling FFAG accelerator and is presently under construction at Daresbury Laboratory in the UK. To probe different parts of the bunch phase space during the acceleration from 10 to 20 MeV (which requires rapid resonance crossing), electron bunches are needed with sufficiently small emittance. To understand the phase space painting into the 3000 mm-mrad EMMA acceptance, we have modelled ALICE (Accelerators and Lasers in Combined Experiments) - which acts as an injector for EMMA - using GPT and compared the estimated emittances with measurements made with a variety of screen-based methods. Although the emittances are not yet as small as desired, we obtain reasonable agreement between simulation and measurement.
Cockcroft Institute, Warrington, Cheshire
We present a simulation study on the reconstruction of the phase space distribution of a beam in the EMMA injection line. The initial step has been to use a Gaussian beam to calculate the phase space distribution and the horizontal and vertical beam projections which would be expected at a screen. The projections obtained from a range of optical configurations are provided as input for reconstructing the phase space distribution using a standard tomography method. The result from the reconstruction can be compared with the known phase space distribution. By taking into account the limited range of quadrupole strengths available, we can determine how practical limitations may affect the reconstruction.
*"EMMA: THE WORLD'S FIRST NON-SCALING FFAG," R. Edgecock, D. Kelliher, S. Machida, STFC/RAL, Didcot, UK et al. in Proceedings of EPAC08, Genoa, Italy