Study of a Long Baseline nu_tau Appearance Neutrino Oscillation Experiment in the Quasi-Elastic Regime

TL;DR

This paper proposes a long baseline experiment using a liquid scintillator detector to observe nu_tau appearance via quasi-elastic interactions, aiming to explore neutrino oscillation parameters related to the atmospheric neutrino anomaly.

Contribution

It introduces a detailed design for a 15-kiloton liquid scintillator detector optimized for nu_tau detection in a long baseline setup, focusing on quasi-elastic interactions and background rejection.

Findings

Detector optimized for tau decay electron identification.

Effective background suppression from pi^0 and beam contamination.

Potential to probe high sin^2(2theta) and low Delta m^2 regions.

Abstract

We present a study for a design of a long baseline nu_mu to nu_tau appearance experiment to probe the high sin^2(2theta) and low Delta m^2 region relevant to explain the atmospheric neutrino anomaly. The experiment relies on a good identification of quasi-elastic interactions, which is a clean topology that has an important contribution in the lowest Delta m^2 part of the region probed. The detector we studied is a fine grained liquid scintillator detector of 15 kilotons, optimized to detect electrons from tau -> e bar(nu_e) nu_tau decays, while rejecting backgrounds from pi^0 in nu_mu interactions and electrons from the nu_e beam contamination. As a reference, the proposed nu_mu neutrino beam from CERN to Gran Sasso was used.