He And Ne Isotopes In Radiation Belts Observed By Hit Onboard Tsubasa Satellite

The energetic heavy ions from helium to iron were observed by Heavy Ion Telescope (HIT) onboard the TSUBASA satellite from March, 2002 to September, 2003 in the geostationary transfer orbit. Their isotopes were also separated that the mass resolution is similar to 0.24 amu for helium isotopes and similar to 0.35 amu for neon isotopes. He-3 and He-4 for helium with 20-40 MeV/n and Ne-20 and Ne-22 for neon with 50-100 MeV/n in the quiet periods were analyzed to obtain the spatial and temporal variation of fluxes of both isotopes. The enhancement of He-3 flux as compared with He-4 one in the region than 2L was found, while no neon isotopes were observed in the same region. Moreover, the ratios of He-3/He-4 and Ne-22/Ne-20 in the region than 3L are comparable to those of galactic cosmic rays. These results might suggest that the injection and loss mechanism of heavy ions differ between inner and outer radiation belts.