16:30 〜 16:45
[SGC38-05] Earth’s radiogenic power and composition revealed with geoneutrinos
キーワード：geoneutrinos, Earth's composition, Earth's power, Radiogenic power, Heat producing elements
Earth's composition and amount of radiogenic power driving its engine remains a controversial subject. Earth's dynamics are driven by primordial and radiogenic heat sources. Measuring the planet's geoneutrino flux (electron antineutrinos from Th and U) defines its radiogenic power and constrains its bulk composition. Here we present a geological analysis of the lithosphere (crust and mechanically coupled mantle) surrounding the KamLAND detector (Japan), currently measuring the Earth's geoneutrino flux, and accurately determine the radiogenic contributions of the lithosphere and mantle to the total signal.
A geological re-analysis of the lithosphere surrounding the Borexino detector (Italy) shows it contains typical crustal abundances of the heat producing elements, contrary to results that reported in Agostini et al. (2020, Phys. Rev. D).
The SNO+ detector (Canada) has been measuring the Earth's geoneutrino emission for more than a year and a geological analysis of its lithosphere has predicted it expected flux. It is anticipated that this experiment will report its findings in one to two more years. Together these three detectors provide a global coverage of the northern hemisphere’s mantle contribution to the Earth's geoneutrino flux.
The JUNO detector (China) is under construction. This detector will be 20 times bigger than existing detectors. Geological analyses of its surrounding lithosphere has produced competing predictions of its expected flux. Efforts are under way to reconcile these geological models.
Accordingly, existing particle physics results constrain the Earth's remaining fraction of primordial energy. A combined data analysis using KamLAND and Borexino geoneutrino experiments affirms the Earth has 20 (+7, -9) TW of radiogenic power, 20 ng/g U and 76 ng/g Th, and sets the proportions of refractory lithophile elements at 2.7 times that in CI carbonaceous chondrites.
A geological re-analysis of the lithosphere surrounding the Borexino detector (Italy) shows it contains typical crustal abundances of the heat producing elements, contrary to results that reported in Agostini et al. (2020, Phys. Rev. D).
The SNO+ detector (Canada) has been measuring the Earth's geoneutrino emission for more than a year and a geological analysis of its lithosphere has predicted it expected flux. It is anticipated that this experiment will report its findings in one to two more years. Together these three detectors provide a global coverage of the northern hemisphere’s mantle contribution to the Earth's geoneutrino flux.
The JUNO detector (China) is under construction. This detector will be 20 times bigger than existing detectors. Geological analyses of its surrounding lithosphere has produced competing predictions of its expected flux. Efforts are under way to reconcile these geological models.
Accordingly, existing particle physics results constrain the Earth's remaining fraction of primordial energy. A combined data analysis using KamLAND and Borexino geoneutrino experiments affirms the Earth has 20 (+7, -9) TW of radiogenic power, 20 ng/g U and 76 ng/g Th, and sets the proportions of refractory lithophile elements at 2.7 times that in CI carbonaceous chondrites.