Distinguishing Dirac from Majorana neutrinos in a microwave cavity

Abstract

We propose a novel scheme for distinguishing between the Dirac and Majorana nature of neutrinos via interaction of a neutrino beam with microwave photons inside a cavity. We study the effective photon-photon polarization exchange induced by the photon-neutrino scattering. The quantum field theoretical studies of such effective picture are presented for both Dirac and Majorana neutrinos. Our phenomenological analyses show that the difference between Dirac and Majorana neutrinos can manifest itself in scattering rate of the photons. To enhance the effect a cavity scheme is employed. An experimental setup based on microwave cavities is then designed and simulated by finite element method to measure the scattering rate. Our results suggest that an experiment based on the current state-of-the-art technology will be able to probe the difference in about one year. However, it can be done in a few days by enhancing the neutrino beam flux or implementing with the near future equipments. Therefore, our work provides the possibility %puts the grounds for solving the long lasting puzzle of Dirac or Majorana nature of neutrinos.