Physics potential of ESSνSB in the presence of a light sterile neutrino

Abstract

Abstract ESSνSB is a proposed neutrino super-beam project at the ESS facility. We study the performance of this setup in the presence of a light eV-scale sterile neutrino, considering 540 km baseline with 2 years (8 years) of ν ( $$ \overline{\nu} $$ ν ¯ ) run-plan. This baseline offers the possibility to work around the second oscillation maximum, providing high sensitivity towards CP-violation (CPV). We explore in detail its capability in resolving CPV generated by the standard CP phase δ 13, the new CP phase δ 14, and the octant of θ 23. We find that the sensitivity to CPV induced by δ 13 deteriorates noticeably when going from 3ν to 4ν case. The two phases δ 13 and δ 14 can be reconstructed with a 1σ uncertainty of ∼ 150 and ∼ 350 respectively. Concerning the octant of θ 23, we find poor sensitivity in both 3ν and 4ν schemes. Our results show that a setup like ESSνSB working around the second oscillation maximum with a baseline of 540 km, performs quite well to explore CPV in 3ν scheme, but it is not optimal for studying CP properties in 3+1 scheme.