タイトル | Pitch angle distributions of low-energy ions in the near-earth magnetosphere |
著者(英) | Whalen, B. A.; Sagawa, E.; Yau, A. W.; Peterson, W. K. |
著者所属(英) | Herzberg Inst. of Astrophysics|Lockheed Missiles and Space Co. |
発行日 | 1987-11-01 |
言語 | eng |
内容記述 | Energetic ion composition data acquired by satellite have been used to study the characteristics of ion pitch angle distributions in the near-earth magnetosphere. Both H(+) and O(+) ions below 1 keV were most frequently observed to have bidirectional field-aligned or conical pitch angle distributions inside L of about 6, with the exception of highly trapped H(+) very near the magnetic equator. The occurrence probability distributions of counterstreaming ions (CSI) and bidirectional conics in magnetic local time and L shell space suggest that the observed CSI were formed near the postmidnight sector and subsequently drifted eastward, and that ions close to the field-aligned direction were probably lost due to charge exchange with atmospheric hydrogen in the course of their eastward drift. In the prenoon sector, conical distributions dominated. Bidirectional ions were vary rarely observed in the afternoon sector, presumably because their drift paths crossed the magnetopause into the dayside magnetosheath. |
NASA分類 | GEOPHYSICS |
レポートNO | 88A20344 |
権利 | Copyright |
URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/373470 |
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