TITUS: An Intermediate Distance Detector for the Hyper-Kamiokande Neutrino Beam

Abstract

The Tokai Intermediate Tank with Unoscillated Spectrum (TITUS) detector is a proposed addition to the Hyper-Kamiokande (HK) experiment located approximately 2 km from the J-PARC neutrino beam. The design consists of a 2 kton Gadolinium (Gd) doped water Cherenkov detector, surrounded by a magnetized iron detector designed to range-out muons. The target material and location are chosen so that the neutrino interactions and beam spectrum at TITUS will match those of HK. Including a 0.1% Gd concentration allows for neutrino/antineutrino discrimination via neutron tagging. The primary goal of TITUS is to directly measure the neutrino flux and make cross-section measurements that reduce the systematic uncertainty of the long-baseline oscillation physics program at HK and enhance its sensitivity to CP violation. TITUS can also be used for physics unrelated to the J-PARC beam, functioning as an independent detector for supernova neutrino bursts and measuring the neutron rate to improve HK proton decay searches.