Probing neutrino parameters with a Two-Baseline Beta-beam set-up

TL;DR

This paper explores a two-baseline Beta-beam setup with different detectors and ion sources to improve sensitivity to neutrino mass parameters, CP violation, and mass ordering, achieving significant detection prospects.

Contribution

It proposes a novel two-detector, two-baseline Beta-beam configuration optimized for probing neutrino parameters with high sensitivity, including maximal CP violation and mass hierarchy.

Findings

Can probe maximal CP violation and establish neutrino mass ordering at very small $ heta_{13}$.

Sensitivity to $ heta_{13}$ down to $5.3 imes 10^{-5}$.

CP violation detectable for 64% of $ heta_{13}$ and $dcp$ parameter space.

Abstract

We discuss the prospects of exploring the neutrino mass parameters with a CERN based Beta-beam experiment using two different detectors at two different baselines. The proposed set-up consists of a 50 kton iron calorimeter (ICAL) at a baseline of around 7150 km which is roughly the magic baseline, e.g., ICAL@INO, and a 50 kton Totally Active Scintillator Detector at a distance of 730 km, e.g., at Gran Sasso. We take 8B and 8Li source ions with a boost factor $\gamma$ of 650 for the magic baseline while for the closer detector we consider 18Ne and 6He ions with a range of Lorentz boosts. We find that the locations of the two detectors complement each other leading to an exceptional high sensitivity. With $\gamma=650$ for 8B/8Li and $\gamma=575$ for 18Ne/6He and total luminosity corresponding to $5\times (1.1\times 10^{19})$ and $5\times (2.9\times 10^{19})$ useful ion decays in neutrino and antineutrino modes respectively, we find that the two-detector set-up can probe maximal CP violation and establish the neutrino mass ordering if $\sin^22\theta_{13}$ is $1.8 \times 10^{-5}$ and $4.6 \times 10^{-5}$, respectively, or more. The sensitivity reach for $\sin^22\theta_{13}$ itself is $5.3 \times 10^{-5}$. CP violation can be discovered for 64% of the possible $\delta_{CP}$ values for $\sin^22\theta_{13} \geq 8\times 10^{-5}$.