Latitudinal variation of the solar He I 58.4 nm irradiance from the optical observation of the interplanetary He I emission

摘要: [1] The Extreme Ultraviolet (XUV) scanner on board the Planet-B spacecraft observed He I 58.4-nm emission of local interstellar gas in interplanetary space during solar maximum. The was an orbit with a perihelion 1 AU and aphelion 1.5 encountered helium focusing cone at longitude different from position Earth March April 2000. Numerical simulations XUV observation were carried out based hot model (Wu Judge, 1979) empirical flux (SOLAR2000) (Tobiska et al., 2000). In comparison observations, we obtain ionization rate (2.3 ± 0.27) × 10−7/s line width 0.0098 0.0014 nm, corresponding to velocity 50 7.2 km/s. However, distribution intensity indicates that irradiance has anisotropy latitude. From between alternative no total rate, ratio toward pole within ecliptic plane is estimated be 0.61 0.24. Therefore it suggested atoms similar anisotropies as flux. Since relationship density not linear, three-dimensional time-dependent approach required for full understanding space.