Abstract:The next generation neutrino observatory proposed by the LBNO collaboration will address fundamental questions in particle and astroparticle physics. The experiment consists of a far detector, in its first stage a 20 kt LAr double phase TPC and a magnetised iron calorimeter, situated at 2300 km from CERN and a near detector based on a highpressure argon gas TPC. The long baseline provides a unique opportunity to study neutrino flavour oscillations over their 1st and 2nd oscillation maxima exploring the L/E behaviour, and distinguishing effects arising from δ CP and matter.In this paper we have reevaluated the physics potential of this setup for determining the mass hierarchy (MH) and discovering CP-violation (CPV), using a conventional neutrino beam from the CERN SPS with a power of 750 kW. We use conservative assumptions on the knowledge of oscillation parameter priors and systematic uncertainties. The impact of each systematic error and the precision of oscillation prior is shown. We demonstrate that the first stage of LBNO can determine unambiguously the MH to > 5σ C.L. over the whole phase space. We show that the statistical treatment of the experiment is of very high importance, resulting in the conclusion that LBNO has ∼ 100% probability to determine the MH in at most 4-5 years of running. Since the knowledge of MH is indispensable to extract δ CP from the data, the first LBNO phase can convincingly give evidence for CPV on the 3σ C.L. using today's knowledge on oscillation parameters and realistic assumptions on the systematic uncertainties.

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At the LHC, the interplay between a series of effects (e.g. intrabeam scattering, longitudinal beam manipulations, machine non-linearities) can lead to a tails population change, that may result in non-Gaussian beam distributions. Since the calculated beam size depends on the tail formation, it is important to follow the bunch profile evolution. In this paper, the benchmarking of a Monte-Carlo simulation code able to track 3D particle distributions, with the analytical IBS formulas is discussed. Novel distribution functions are employed to describe the beam profiles, and are used as a guideline for generalizing emittance estimations due to IBS and radiation effects. The impact of the distribution shape on the evolution of the bunch characteristics is studied. Bunch profile observations from the LHC Run 2 are compared to simulations and analytical results.

The theoretical minimum emittance cells are the optimal configurations for achieving the absolute minimum emittance, if specific optics constraints are satisfied at the middle of the cell's dipole.Linear lattice design options based on an analytical approach for the theoretical minimum emittance cells are presented in this paper. In particular the parametrization of the quadrupole strengths and optics functions with respect to the emittance and drift lengths is derived. A multi-parametric space can be then created with all the cell parameters, from which one can chose any of them to be optimized. An application of this approach are finally presented for the linear and non-linear optimization of the CLIC Pre-damping rings.