Simulation Studies of the Directivity in Detection of Solar Neutrinos Using Deep Sea Water

摘要: The Cerenkov detector has a distinct advantage in constructing the reaction vertex and incident direction of energetic particles, enabling the identification of emission sources. We propose a novel approach to measure neutrino sources by employing a modular photomultiplier tube (PMT) array, utilizing clean and transparent deep sea water as the sensitive medium. The feasibility of detecting solar neutrinos is demonstrated through extensive simulations using the Geant4 package. These simulations incorporate the production and transport of Cerenkov photons generated by electron scattering, with the Hough transform method applied to enhance the accuracy of vertex and direction reconstruction, particularly in the presence of noisy or incomplete data. The dominant background from γ-radiation due to 40K in seawater can be suppressed by a factor of 10^7 by introducing a threshold on the number of triggered PMTs. The total reconstruction efficiency increases with incident energy, achieving 25% for 6 MeV neutrinos and 52% for 10 MeV neutrinos, respectively. For source localization, a sufficient number of neutrino events must be detected, depending on background intensity above the threshold. The Hough transform is also applied to manage high noise levels during this process. The simulation results confirm the feasibility of detecting solar neutrinos using deep sea water, paving the way for future underwater neutrino detection systems.