11:45 〜 12:00
[SIT21-05] Theoretical Insights into Earth's Heat from Geoneutrino Detection by Ocean Bottom Detector: Role of Angular Resolution
キーワード：地球ニュートリノ、マントル、LLSVP、放射性物質、地熱
Geoneutrinos are elementary particles produced by the β-decays of radioactive isotopes within the Earth. Detecting these particles not only enables us to study the Earth's heat but also helps determine the abundance of radioactive isotopes and even other elements. However, due to their extremely small mass and interactions limited to the weak and gravitational forces, geoneutrinos are incredibly challenging to detect.
Nonetheless, in 2005, the KamLAND experiment (Japan) became the first ever to successfully observe geoneutrinos, providing groundbreaking insights into the Earth's interior. This achievement spurred the development of new methods for studying the Earth's structure, bridging neutrino physics with geochemistry and geophysics. The Borexino experiment (Italy) later confirmed geoneutrino detection, and ongoing projects such as SNO+ (Canada) and the upcoming JUNO experiment (China) aim to further our understanding of the Earth's interior through continued geoneutrino observations.
However, the detectors mentioned above are all located on thick continental crusts, and the high concentration of radioactive isotopes in these crusts limits our ability to investigate deeper layers of the Earth. To address this challenge, a project called Ocean Bottom Detector (OBD) has been proposed. This initiative involves placing a neutrino detector on the ocean floor off the coast of Hawaii, where the oceanic crust is thin and contains fewer radioactive isotopes. This makes the location ideal for directly detecting geoneutrinos from the mantle.
A key challenge is that traditional detection methods lack the angular resolution needed to determine the direction of incoming neutrinos, making it difficult to confirm whether a detected neutrino truly originates from the Earth's interior. In recent years, new techniques have been developed that enable neutrino detectors to achieve angular resolution. In this talk, we will explore the potential observational results that could be obtained if OBD is equipped with angular resolution. Such observations could not only provide direct evidence of geoneutrinos' directionality but also offer valuable insights into the structure and dynamics of the Earth's deep interior, including features like large low-shear-velocity provinces (LLSVPs) and superplumes.
Nonetheless, in 2005, the KamLAND experiment (Japan) became the first ever to successfully observe geoneutrinos, providing groundbreaking insights into the Earth's interior. This achievement spurred the development of new methods for studying the Earth's structure, bridging neutrino physics with geochemistry and geophysics. The Borexino experiment (Italy) later confirmed geoneutrino detection, and ongoing projects such as SNO+ (Canada) and the upcoming JUNO experiment (China) aim to further our understanding of the Earth's interior through continued geoneutrino observations.
However, the detectors mentioned above are all located on thick continental crusts, and the high concentration of radioactive isotopes in these crusts limits our ability to investigate deeper layers of the Earth. To address this challenge, a project called Ocean Bottom Detector (OBD) has been proposed. This initiative involves placing a neutrino detector on the ocean floor off the coast of Hawaii, where the oceanic crust is thin and contains fewer radioactive isotopes. This makes the location ideal for directly detecting geoneutrinos from the mantle.
A key challenge is that traditional detection methods lack the angular resolution needed to determine the direction of incoming neutrinos, making it difficult to confirm whether a detected neutrino truly originates from the Earth's interior. In recent years, new techniques have been developed that enable neutrino detectors to achieve angular resolution. In this talk, we will explore the potential observational results that could be obtained if OBD is equipped with angular resolution. Such observations could not only provide direct evidence of geoneutrinos' directionality but also offer valuable insights into the structure and dynamics of the Earth's deep interior, including features like large low-shear-velocity provinces (LLSVPs) and superplumes.