Use of a pulse shape analysis of recoil electron signals in a liquid ionization chamber for indication of the direction of incidence of low energy photons and neutrinos

Abstract

It is shown that the direction of incidence of photons and neutrinos with energies above 0.5 MeV can be determined by pulse shape analysis of recoil electron signals in a liquid ionization chamber. The experiments were carried out using a liquid argon ionization chamber. For 0.622–3.2 MeV photons the direction of incidence can be determined within the cone ±(40°−70°) depending on energy. A detailed Monte-Carlo calculation demonstrated the possibility of the suppression of the isotropic background by an order of magnitude for a recoil electron energy above 2–3 MeV.