BAIKAL DUMAND : Extremely High Energy Neutrino Astrophysics

点击翻译按钮获取中文摘要

In this program, we have planned to study various fundamental researches for extremely high energy neutrino astrophysics which has never existed as the brancn of science up to now. In our opinion, one of the biggest characteristics of extremely high energy neutrino astrophysics lies in to observe the universe, the existence of which is never observed by light1 but only by neutrino. The purpose of this program is to develop techniques and theoretical concepts by which such universe could be observed.We are developing new types of high performance of photon counters based the semiconductor technique, namely counters with both local feed back type and superlattice types (Reference No.14), because the conventional type of photo-multipliers which have been extensively utilized in the Superkamiokande experiment have lost effectiveness in the extremely high energy neutrino astrophysics. Extremely high energy neutrino is detected by the measurement of the emitted Cherenkov radiation from both electron (in the case of electron neutrino) and muon (in the case of muonneutrino). As for electron, we investigated such electron showers in the plasma state (Re.No.1) these in strong magnetic field(Re.No.3) and the LPM effect problems (Re.No.8,9). As for muon, the influence of the heavy atom on the bremsstralilung (Re.no.13) and atmospheric muon problem (Re.No.18) are investigated. Also, the knowledge on the space-temporal structure is requested to detect neutrino(Re.No.10). On the other hand, experimental knowledge on high energy neutrino which is absolutely important for the understanding of behavior of extremely high energy neutrino is obtained (Re.No.5,6,7).