Future neutrino oscillation facilities

The recent discovery that neutrinos have masses opens a wide new field of experimentation. Accelerator-made neutrinos are essential in this program. Ideas for future facilities include high intensity muon neutrino beams from pion decay (`SuperBeam'), electron neutrino beams from nuclei decays (`Beta Beam'), or muon and electron neutrino beams from muon decay (`Neutrino Factory'), each associated with one or several options for detector systems. Each option offers synergetic possibilities, e.g. some of the detectors can be used for proton decay searches, while the Neutrino Factory is a first step towards muon colliders. A summary of the perceived virtues and shortcomings of the various options, and a number of open questions are presented.Comment: Originally written for the CERN Strategy Grou

The inclusive reaction pp=pX at the CERN ISR

Experiments at the CERN ISR have given evidence for proton single-dissociation processes where the missing mass of the system X, measured on the proton which is observed in the reaction p + p → p + X, presents a distribution extending up to large values , in the 10 GeV range. These processes globally account for ∼15% of the inelastic p-p cross section. Evidence for such a distinct class of inelastic phenomena is also provided by long-range rapidity correlations and clustering. The nature of these processes appears to be predominantly diffractive. The physics which emerges from ISR observations is discussed , together with a presentation of present and planned lines of experimental investigation at the ISR

Sensitivity on Earth Core and Mantle densities using Atmospheric Neutrinos

Neutrino radiography may provide an alternative tool to study the very deep structures of the Earth. Though these measurements are unable to resolve the fine density layer features, nevertheless the information which can be obtained are independent and complementary to the more conventional seismic studies. The aim of this paper is to assess how well the core and mantle averaged densities can be reconstructed through atmospheric neutrino radiography. We find that about a 2% sensitivity for the mantle and 5% for the core could be achieved for a ten year data taking at an underwater km^3 Neutrino Telescope. This result does not take into account systematics related to the details of the experimental apparatus.Comment: 11 pages, 11 figures, accepted for publication in JCA

Stand-alone Low Power Consumption FEE and DAQ for the Readout of Silicon Photomultipliers

We developed a front end electronics (FEE) and data acquisition (DAQ) system with a low power consumption, especially intended for stand-alone applications in unattended environments without standard electricity supply. The system works autonomously thanks to dedicated algorithms that are embedded. The FEE is based on the EASIROC chip, designed for the readout of Silicon photomultipliers (SiPMs). It digitizes the amplitude of the signals and provides time information with time of flight capability. The trigger logic is programmable and physical and accidental coincidences rates can be measured. The SiPMs temperature is controlled by thermoelectric cells. Thanks to a network of temperature and humidity sensors, a real-time software sets the optimal operating point of the SiPMs depending on external conditions and if necessary halts the system to avoid damage to the electronics. The system has been used in several muon radiography experiments

Electron/pion separation with an Emulsion Cloud Chamber by using a Neural Network

We have studied the performance of a new algorithm for electron/pion separation in an Emulsion Cloud Chamber (ECC) made of lead and nuclear emulsion films. The software for separation consists of two parts: a shower reconstruction algorithm and a Neural Network that assigns to each reconstructed shower the probability to be an electron or a pion. The performance has been studied for the ECC of the OPERA experiment [1]. The $e/\pi$ separation algorithm has been optimized by using a detailed Monte Carlo simulation of the ECC and tested on real data taken at CERN (pion beams) and at DESY (electron beams). The algorithm allows to achieve a 90% electron identification efficiency with a pion misidentification smaller than 1% for energies higher than 2 GeV

Charged-Particle Multiplicities in Charged-Current Neutrino-- and Anti-Neutrino--Nucleus Interactions

The CHORUS experiment, designed to search for $\nu_{\mu}\to\nu_{\tau}$ oscillations, consists of a nuclear emulsion target and electronic detectors. In this paper, results on the production of charged particles in a small sample of charged-current neutrino-- and anti-neutrino--nucleus interactions at high energy are presented. For each event, the emission angle and the ionization features of the charged particles produced in the interaction are recorded, while the standard kinematic variables are reconstructed using the electronic detectors. The average multiplicities for charged tracks, the pseudo-rapidity distributions, the dispersion in the multiplicity of charged particles and the KNO scaling are studied in different kinematical regions. A study of quasi-elastic topologies performed for the first time in nuclear emulsions is also reported. The results are presented in a form suitable for use in the validation of Monte Carlo generators of neutrino--nucleus interactions.Comment: 17 pages, 5 figure