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Non scaling Fixed-Field Alternating Gradient (FFAG) accelerators have an unprece- dented potential for muon acceleration, as well as for medical purposes based on car- bon and proton hadron therapy. They also represent a possible active element for an Accelerator Driven Subcritical Reactor (ADSR). Starting from first principle the Hamil- tonian formalism for the description of the dynamics of particles in non-scaling FFAG machines has been developed. The stationary reference (closed) orbit has been found within the Hamiltonian framework. The dependence of the path length on the energy deviation has been described in terms of higher order dispersion functions. The latter have been used subsequently to specify the longitudinal part of the Hamiltonian. It has been shown that higher order phase slip coefficients should be taken into account to adequately describe the acceleration in non-scaling FFAG accelerators. A complete theory of the fast (serpentine) acceleration in non-scaling FFAGs has been developed. An example of the theory is presented for the parameters of the Electron Machine with Many Applications (EMMA), a prototype electron non-scaling FFAG to be hosted at Daresbury Laboratory.

The hourglass effect arises due to a coupling between the longitudinal and transverse bunch planes. This coupling will result in a charge density distribution that will vary parabolically through the Interaction Point (IP). Here a method of analytically determining the electric field a particle receives from a charge density distribution which varies parabolically when centred at the IP, is derived for a 2D transverse model of a Gaussian bunch.

Simulations of β$^∗$ luminosity levelling using the strongstrong beam-beam code COMBI are undertaken. Simulations for both flat and round beam profiles are discussed and analysed with respect to the coherent spectra. It is shown that bunches with a round beam profile will have a beambeam parameter that is independent of β$^∗$ over the levelling steps. Flat bunches however will have a beam-beam parameter that is dependent on β$^∗$ over the levelling steps since the beam aspect ratio will change. This will change the tune of the π-mode as the β$^∗$ is levelled, which could lead to a resonance crossing.

We present the progress with the design of the 2.25 GeV superconducting linac for the NLS project. We discuss the performance achieved, the rationale for the most recent modifications of the linac design, the relevance of microbunching instability and the analysis of the effect of various jitter sources.

EMMA (Elec­tron Ma­chine with Many Ap­pli­ca­tions) is a pro­to­type non-scal­ing Fixed Field Al­ter­nat­ing Gra­di­ent (NS-FFAG) ac­cel­er­a­tor present­ly under con­struc­tion at Dares­bury Lab­o­ra­to­ry, UK. The en­er­gy re­cov­ery linac ALICE will serve as an in­jec­tor for EMMA with­in the en­er­gy range of 10 to 20 MeV. The in­jec­tion line con­sists of a sym­met­ric 30° dog­leg to ex­tract the beam from ALICE, a match­ing sec­tion and a to­mog­ra­phy sec­tion for trans­verse emit­tance mea­sure­ments. This is fol­lowed by a trans­port sec­tion to the in­jec­tion point of the EMMA ring. Com­mis­sion­ing of the EMMA in­jec­tion line start­ed in early 2010. A num­ber of dif­fer­ent in­jec­tion en­er­gy and bunch charge regimes are planned; for some of the regimes the ef­fects of space charge will be sig­nif­i­cant. It is there­fore nec­es­sary to model the elec­tron beam trans­port in this line using a code ca­pa­ble of both cal­cu­lat­ing the ef­fect of, and com­pen­sat­ing for, space charge. There­fore the Gen­er­al Par­ti­cle Trac­er (GPT) code has been used. A range of in­jec­tion beam pa­ram­e­ters have been mod­elled for com­par­i­son with ex­per­i­men­tal re­sults.

EMMA (ElectronModel 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.

EMMA (Elec­tron Ma­chine with Many Ap­pli­ca­tions) is a pro­to­type non-scal­ing elec­tron FFAG to be host­ed at Dares­bury Lab­o­ra­to­ry. NS-FFAGs re­lat­ed to EMMA have an un­prece­dent­ed po­ten­tial for med­i­cal ac­cel­er­a­tors for car­bon and pro­ton hadron ther­a­py. It also rep­re­sents a pos­si­ble ac­tive el­e­ment for an ADSR (Ac­cel­er­a­tor Driv­en Sub-crit­i­cal Re­ac­tor). This paper sum­maris­es the com­mis­sion­ing plans for this ma­chine to­geth­er with the major steps and ex­per­i­ments in­volved along the way. A de­scrip­tion of how the 10 to 20 MeV beam is achieved with­in ALICE is also given, as well as ex­trac­tion from the EMMA ring to the di­ag­nos­tics line and then dump.

Beam tomography research at Daresbury Laboratory has focussed on the development of normalised phase space techniques—starting with the idea of sampling tomographic projections at equal phase advances. This idea has influenced the design and operation of the tomography sections at the Photo Injector Test Facility at Zeuthen (PITZ) and at the Accelerator and Lasers in Combined Experiments (ALICE) at Daresbury. We have studied the feasibility of using normalised phase space to measure the effect of space charge. Quadrupole scan measurements are carried out at two different parts of a beamline. Reconstructions at the same location give results that are clearly rotated with respect to each other in normalised phase space. We are able to show that a significant part of this rotation can be attributed to the effect of space charge. We show how the normalised phase space technique can be used to increase the reliability of the Maximum Entropy Technique (MENT). While MENT is known for its ability to work with just a few projections, the accuracy of its reconstructions has seldom been questioned. We show that for typical phase space distributions, MENT could produce results that look quite different from the original. We demonstrate that a normalised phase space technique could give results that are closer to the actual distribution. We also present simpler ways of deriving the phase space tomography formalism and the Maximum Entropy Technique.

Recent progress with the design of the UK's proposed New Light Source facility is presented, together with an update on the current status.

The conceptual design of CLARA, a novel FEL test facility focussed on the generation of ultra-short photon pulses with extreme levels of stability and synchronisation is described. The ultimate aim of CLARA is to experimentally demonstrate that sub-coherence length pulse generation with FELs is viable, and to compare the various schemes being championed. The results will translate directly to existing and future X-ray FELs, enabling them to generate attosecond pulses, thereby extending the science capabilities of these intense light sources. This paper will describe the design of CLARA, pointing out the flexible features that will be incorporated to allow multiple novel FEL schemes to be proven. Copyright © 2013 by JACoW.