Tohoku University Graduate School of Science
Tohoku University Graduate School of Science
Tohoku University Graduate School of Science
Tohoku University Graduate School of Science
出版者
宇宙航空研究開発機構宇宙科学研究本部
出版者（英）
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)
雑誌名
第39回月・惑星シンポジウム
雑誌名(英)
Proceedings of the 39th ISAS Lunar and Planetary Symposium
ページ
33 - 36
発行年
2006-08-07
抄録（英）
The Jovian Synchrotron Radiation (JSR) is a radio wave emitted from the relativistic electrons in the Jovian radiation belt, which has information of dynamics of high-energy particles and electromagnetic disturbances in the Jovian inner magnetosphere. JSR is known to both indicate long-term (11 year) and short-term (day to weeks) variations but the short-term variation has not been studied well because of few continuous observation. Then we have observed JSR for several months a year since 1994 to reveal characteristics of the flux variations especially at time variations. The regular observations have been made at a frequency of 327 MHz by using parabolic cylinder antennas of the Solar Terrestrial Environment Laboratory (STEL), Nagoya University. The observed JSR flux includes apparent variation due to inevitable system gain variation of the radio receiving system. In order to compensate the system gain variation, Nomura et al., (2005), have evaluated the system gain using a flux reference radio source that was observed quasi-simultaneously with Jupiter, and made additional observations of 'actual' galactic Back-Ground radiation (BG) with the highly stable radio receiving system of Tohoku University. In this study, we have derived the JSR flux densities to improve reliability of the JSR flux densities by revaluation of BG radiation using a revised technique. As the result, we derived the JSR flux densities for 1995 and 1996 with the error range of about 50 percent. We report the improved results of the JSR observations and infer causalities of the variations based on correlation analyses between the JSR flux variations and parameters of the solar activity and solar wind.
Characteristics of short term variations of the Jovian synchrotron radiation at a frequency of 327 MHz
