The Phenomenology of Ultra High Energy Astrophysical Neutrinos

The development of km-scale neutrino telescopes is now realizing the neutrino astronomy. Astrophysical high energy neutrinos have been considered crucial for understanding the origin of ultra high energy cosmic rays and expected to provide a parallel observation on exotic object in the universe such as gamma ray bursts, active galactic nuclei and supernovae. In our previous research, the viability to detect neutrinos of origins different from canonical pion sources with a flavor composition of (1, 1, 1). We also proposed a parametrization of neutrino flavor transition mechanism to probe transition models other than the standard neutrino oscillation. The possibility that neutrino telescopes can provide a parallel test of neutrino physics as well as astrophysics relies on the capability of identifying different flavors of neutrinos. This capability stimulates the flavor astronomy. To measure the neutrino flavor ratio to sufficient precision requires understanding of different behaviors for each flavor. For neutrino telescopes such ARA and ANITA, neutrinos are observed by detecting radio Cherenkov radiation. Taking the advantage of the collaboration with NTU’s ARA team, we study neutrino physics in ARA-like neutrino telescopes. We will investigate the detail of the propagation for different flavors, study the structure and topology of the induced showers and simulate the emitted radio signals. Combining all these knowledge, we try to propose a method of discrimination between different flavors and apply it to neutrino telescopes with specified layout and configuration. Once the detector measures radio signals produced by high energy neutrinos, the flavor can be inferred by our simulation and the simulation can be improved accordingly as well. In the near future, neutrino telescopes should score certain number of astrophysical high energy neutrino events so that we can test and refine our study. Our work in previous project will also be reviewed.

Project ID:PA10208-0172
External Project ID:NSC102-2112-M182-001