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"Beta Beams" produce collimated pure electron (anti-) neutrino beams by accelerating beta active ions to high energies and having them decay in a race track shaped storage ring of 7 km circumference, the Decay Ring. EUROnu Beta Beams are based on CERN infrastructures and existing machines. Using existing machines may be an advantage for the cost evaluation, however, this choice is also constraining the Beta Beams. The isotope pair of choice for the Beta Beam is 6He and 18Ne. However before the EUROnu studies one of the needed isotopes, 18Ne, could not be produced in rates that satisfy the needs for physics reach of the Beta Beam. Therefore, studies of alternative beta emitters, 8Li and 8B, with properties interesting for a Beta Beam have been proposed and have been studied within EUROnu. These alternative isotopes could be produced by using a small storage ring, in which the beam traverses a target, creating the 8Li and 8B isotopes. This Production Ring, the injection Linac and the target system have been evaluated. Measurements of the cross-section of the reactions to produce the Beta Beam isotopes show interesting results. A device to collect the produced isotopes from the target has been developed and tested. However, the obtained rates of the 8Li and 8B, using the Production Ring for production of 8Li and 8B, is not yet, according to simulations, giving the rates of isotopes that would be needed. Therefore, a new method of producing the 18Ne isotope has been developed and tested giving good production rates. The baseline presented for the Beta Beam is therefore now to use the 6He and 18Ne isotopes for neutrino production. A 60 GHz ECRIS prototype, the first in the world, was developed and tested with contributions from EUROnu. The Beta Beam has to take into account the modifications of the injectors planned in view of LHC-upgrades. The Decay Ring lattices for the 8Li and 8B have been developed, the lattice for 6He and 18Ne has been optimized also to ensure the high intensity ion beam stability.

Longitudinal and transverse instabilities in the isochronous accumulator for the CERN proton driver are studied, in order to find cures and set limits to the machine impedance.

The electron cloud may cause transverse single-bunch instabilities of proton beams such as those in the Large Hadron Collider (LHC) and the CERN Super Proton Synchrotron (SPS). We simulate these instabilities and the consequent emittance growth with the code HEADTAIL, which models the turn-by-turn interaction between the cloud and the beam. Recently some new features were added to the code, in particular, electric conducting boundary conditions at the chamber wall, transverse feedback, and variable beta functions. The sensitivity to several numerical parameters has been studied by varying the number of interaction points between the bunch and the cloud, the phase advance between them, and the number of macroparticles used to represent the protons and the electrons. We present simulation results for both LHC at injection and SPS with LHC-type beam, for different electron-cloud density levels, chromaticities, and bunch intensities. Two regimes with qualitatively different emittance growth are observed: above the threshold of the transverse mode-coupling (TMC) type of instability there is a rapid blowup of the beam, while below this threshold a slow, long-term, emittance growth remains. The rise time of the TMC instability caused by the electron cloud is compared with results obtained using an equivalent broadband resonator impedance model, demonstrating reasonable agreement.

Several simulation codes have been adapted so as to model the single-bunch electron-cloud instability including a realistic variation of the optical functions with longitudinal position. In addition, the electron cloud is typically not uniformly distributed around the ring, as frequently assumed, but it is mainly concentrated in certain regions with specific features, e.g., regions which give rise to strong multipacting or suffer from large synchrotron radiation flux. Particularly, electrons in a dipole magnet are forced to follow the vertical field lines and, depending on the bunch intensity, they may populate two vertical stripes, symmetrically located on either side of the beam. In this paper, we present simulation results for the CERN SPS and LHC, which can be compared with measurements or analytical predictions.

Neutrino oscillations have implications for the Standard Model of particle physics. The CERN Beta Beam has outstanding capabilities to contribute to precision measurements of the parameters governing neutrino oscillations. The FP7 collaboration EUROnu (2008-2012) is a design study that will review three facilities (Super-Beams, Beta Beams and Neutrino Factories) and perform a cost assessment that, coupled with the physics performance, will give means to the European research authorities to make decisions on future European neutrino oscillation facilities. "Beta Beams" produce collimated pure electron (anti)neutrinos by accelerating beta active ions to high energies and having them decay in a storage ring. Using existing machines and infrastructure is an advantage for the cost evaluation; however, this choice is also constraining the Beta Beams. Recent work to make the Beta Beam facility a solid option will be described: production of Beta Beam isotopes, the 60 GHz pulsed ECR source development, integration into the LHC-upgrades, insure the high intensity ion beam stability, and optimizations to get high neutrino fluxes. The costing approach will also be described. Copyright ?????? 2012 by IEEE.