[14a-E204-1~8] 2.3 Application, radiation generators, new technology

△ [14a-E204-6] Neutron Spectrometer for Exploration of Near-Earth Asteroids

〇(M1C)Junya Ishii¹, Nobuyuki Hasebe^1,2, Hiroshi Nagaoka², Masayuki Naito¹, Aoki Daisuke¹, Kimura Yuri¹ (1.School adv. Waseda Univ., 2.Inst. Waseda Univ.)

Keywords:neutron spectrometer, near earth asteroids, hydrogen

In Japan, the exploration of Near-Earth Asteroids (NEAs) is expected by a deep space microsatellite. The hydrogen in asteroids is one of the important elements for space resource. Neutron flux emitted from planetary surface with thin or no atmosphere is sensitive to the presences of light elements, especially hydrogen, since it acts as an effective moderator for neutron transportation. Therefore, the hydrogen concentration in NEAs is determined by comparing the neutron fluxes in energy ranges in energy range of thermal (< 1 eV), epithermal (1 eV - 500 keV) and fast (< 500 keV) neutron. Measurement of neutron flux provides useful information to characterize the composition of NEAs. We estimate the ability of neutron measurement by neutron spectrometer which consists of two type scintillators, 1) lithium glass scintillator which detects thermal neutron and 2) boron loaded plastic scintillator which detects epithermal and fast neutron separately. Our numerical and experimental studies for development neutron spectrometer for the future exploration of NEAs by deep space microsatellite are presented.