| タイトル | Altitude variation of EUV emissions and evidence for proton precipitation at low latitudes in the Saturnian atmosphere |
| 著者（英） | Yelle, R. V.; Shemansky, D. E.; Kumar, S.; Sandel, B. R. |
| 著者所属（英） | Arizona Univ. |
| 発行日 | 1986-08-01 |
| 言語 | eng |
| 内容記述 | Extreme ultraviolet observations of Saturn from Voyager 1 and 2 are analyzed. The Lyman alpha and H2 band emissions extend throughout the upper atmosphere, from the hydrocarbon homopause to well above the exobase. Analysis of the Lyman alpha emissions with a radiative transfer model indicates that the Lyman alpha source temperature is very high. This suggests that energetic protons or hydrogen atoms are responsible for a fraction of the emissions. Calculation of the solar-scattered component of the emissions based on the neutral atmosphere of Smith et al. (1983) reveals that only 1-2 kR out of a total of 3.5 kR of the observed Lyman alpha intensity is due to solar scatter for the Voyager 2 disk observations; the remainder of the Lyman alpha emissions are collisionally excited. The Lyman alpha and H2 bands are constant in longitude but decrease in local time by a factor of 2 from dawn to dusk. This correlation of the Lyman alpha and H2 band intensities is further evidence that most of the Lyman alpha is collisionally excited. |
| NASA分類 | LUNAR AND PLANETARY EXPLORATION |
| レポートNO | 87A12305 |
| 権利 | Copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/381741 |
