[en] In this Letter we quantify the trade-off between setups optimized to be ancillary to Phase II Superbeams or Neutrino Factories and experiments tuned for maximal sensitivity to the subdominant terms of the neutrino transition probability at the atmospheric scale ('maximum discovery potential'). In particular, the θ₁₃ sensitivity is computed for both Phase I superbeams (JHF-SK and NuMI off-axis) and next generation long baseline experiments (ICARUS, OPERA and MINOS). It is shown that Phase I experiments cannot reach a sensitivity able to ground (or discourage in a definitive manner) the building of Phase II projects and that this capability is almost saturated by high energy beams like CNGS, especially for high values of the ratio Δm²₂₁/vertical bar Δm²₃₁ vertical bar

[en] The experimental problem of the calibration of magnetic field in large iron detectors is discussed. Emphasis is laid on techniques based on ballistic measurements as the ones employed by MINOS or OPERA. In particular, we provide analytical formulas to model the behavior of the apparatus in the transient regime, keeping into account eddy current effects and the finite penetration velocity of the driving fields. These formulas ease substantially the design of the calibration apparatus. Results are compared with experimental data coming from a prototype of the OPERA spectrometer

[en] In this paper, it is given a short overview of neutrino oscillation experiments with emphasis on current European programmes of interest for INFN and on mid-term perspectives. In particular, it is discussed the results that strengthen the standard three-family interpretation of leptonic mixing and the tension originating from the persistent LSND-Miniboone anomaly together with updated reactor data.

[en] In the last decade, interest has grown steadily on the design and characterization of novel artificial sources for high-energy neutrinos. In this paper, we outline the physics motivations for these challenging R D and summarize the most relevant achievements of the last few years.

[en] The experimental problem of the calibration of magnetic field in large iron detectors located in underground areas is discussed. Emphasis is laid on techniques based on ballistic measurements as the ones employed by MINOS or OPERA. An experimental investigation of the precision achievable by these methods has been carried out using a full-scale prototype of the OPERA spectrometer built in Frascati in 2001. We demonstrate that a field calibration at the level of 3% can be reached and discuss in details the limiting systematics. Moreover, we provide analytical formulas to model the behaviour of the apparatus in the transient regime, keeping into account eddy current effects and the finite penetration velocity of the driving fields. These formulas ease substantially the design of the calibration apparatus. Finally, ballistic techniques are shown to match the requirements for field calibration at the next generation long-baseline neutrino experiments and are well-suited to operate in underground laboratories

[en] The Beta Beam concept is a very promising technology to achieve high intensity and high purity neutrino beams. The main limitation of the Beta Beam in its baseline configuration ('low-γ option') resides in the smallness of the parent ion energy. Here, the emerging electron neutrinos have an energy of a few hundreds MeV, i.e. a spectrum that significantly limits the physics reach of the facility. Moreover, in order to attain sensitivities comparable to a Phase II Superbeam, the construction of a Mton size detector is mandatory to overcome the smallness of the cross sections. In the following, we discuss a few recent proposals for an increase of the parent ion energy ('high-γ options') with emphasis on physics performances and technological challenges

[en] Long-baseline experiments will play a crucial role in the precision era of neutrino oscillation physics. In this paper we review the ongoing European programme, which is focused on CNGS, and we discuss the opportunities for new facilities based on the CERN acceleration complex

[en] The sensitivity of the present CNGS beam to the sub-dominant ν_μ ↔ ν_e oscillations in the region indicated by the atmospheric neutrino experiments is investigated. In particular, we present a revised analysis of the OPERA detector and discuss the sensitivity to θ₁₃ of ICARUS and OPERA combined. We show that the CNGS beam optimized for ν_τ appearance will improve significantly (about a factor of 5) the current limit of CHOOZ and explore most of the region sin² 2θ₁₃ ≅ O(10^-2). (research notes from collaborations)

[en] Terrestrial neutrino experiments could be the ideal tool to investigate CP violation in the leptonic sector if the θ₁₃ angle of the PMNS matrix is sufficiently high. This condition will be tested by several future long-baseline detectors (Phase I experiments). We discuss the interplay among these experiments and possible synergies. It is shown that, without a dedicated anti ν run, Phase I experiments cannot reach a sensitivity able to ground (or discourage in a definitive manner) the building of the Phase II projects that are aimed at the determination of the leptonic CP phase. In fact, this capability is almost saturated by high energy beams like CNGS, especially for high values of the ratio Δm²₂₁/ vertical stroke Δm²₃₁ vertical stroke. Moreover, we discuss the interplay between on-peak and off-peak experiments and the constraints to the PMNS matrix in case of early evidence for ν_μ → ν_e oscillations at the atmospheric scale (high θ₁₃). (orig.)

[en] We discuss an experimental technique aimed at tagging electron neutrinos in multi-GeV artificial sources on an event-by-event basis. It exploits in a novel manner calorimetric and tracking technologies developed in the framework of the LHC experiments and of rare kaon decay searches. The setup is suited for slow-extraction, moderate power beams and it is based on an instrumented decay tunnel equipped with tagging units that intercept secondary and tertiary leptons from the bulk of undecayed π⁺ and protons. We show that the taggers are able to reduce the ν_e contamination originating from K_e3 decays by about one order of magnitude. Only a limited suppression (∝60%) is achieved for ν_e produced by the decay-in-flight of muons; for low beam powers, similar performance as for K_e3 can be reached supplementing the tagging system with an instrumented beam dump. (orig.)