Can Radiogenic Heat Sources Inside the Earth be located by their Antineutrino incoming Directions?

Abstract

Antineutrinos born in the U and Th decay chains inside the Earth (``Geoneutrinos'') carry out information on the amount and distribution of radiogenic heat sources, which is of fundamental importance for geophysics. Models of the Earth distribute U and Th masses mainly between the continental crust and the lower mantle. It has been much discussed recently that a number of detectors stationed at appropriate geographical sites can separate the crust and mantle contributions. In present work we analyze directional separation of antineutrino signals arriving from the crust and the lower mantle with only one detector. We find that with a ~30-kton liquid scintillation antineutrino spectrometer using $\bar{{\nu}_e}+p \to n + e^{+}$ detection reaction and positron and neutron coordinates reconstruction techniques the U and Th distribution model can roughly be tested. We also consider detector calibration using ~1 MCi commercially available Sr90-Y90 beta source which emits antineutrinos (Emax = 2.28 MeV) in the geoneutrino energy range.