| Summary: | 碩士 === 國立交通大學 === 物理研究所 === 104 === This is a research of the interaction between ultra-high energy astrophysical neutrinos and earth. By introducing the BedMap2 digital elevation model, which has the ice thickness, bed elevation, and surface elevation that are located in Antarctica, we performed Monte-Carlo simulation on the interaction between neutrinos and the local terrain. Before performing the simulation, we selected some locations of astrophysical neutrino observation experiments. Then we calculated the slant depth of all directions by an algorithm and a numerical integration method. Referring to these results, we selected the location of ARIANNA which is located at Ross shelf for our simulations. We constructed a disk shape detector sensitive region for our simulations and generated monoenergetic tau neutrinos at some energy levels between 10^8 GeV and 10^10.5 GeV. The simulation results coincide with our predictions which are according to the slant depth calculations. For 10^10 GeV and 10^10.5 GeV neutrinos we generated, the number of first-generated earth-skimming (The zenith angle θ is between 90° and 91°.) events is relatively low when the azimuth angle φ is between 210° and 300° (Reference vector is pointed to south.). However, the number of regenerated down-going (0° ≤ θ ≤ 89.5°) events is relatively high when 210° ≤ φ ≤ 240°. Most of the regenerated events are tau decay events. For regenerated events, the distributions of shower energy have significant differences between the showers which are created by tau decay and other interaction events.
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