Study on Jupiter's inner magnetosphere by the observation of Jovian synchrotron radiation

1.研制了观测木星同步辐射的接收系统。所研制的前置放大器满足最小检测灵敏度为0.1 Junsky，接收机噪声温度为75k.2的要求。为了准确探测木星的辐射强度，接收机的定标系统已经研制完成。接收系统的相位和增益将使用环路方法进行校准。实现的相对相位差补偿小于5.6，相对增益小于0.2分贝。将研制的接收与校准系统与大型天线系统相连，进行了性能测试。仿真结果表明，天线的波束宽度和接收灵敏度均达到了预期性能要求。成功绘制了频率为327 MHz的银河系无线电波分布图。利用名古屋大学基索天文台和富士天文台的射电望远镜探测到了木星同步辐射的同时强度变化。利用34米大圆盘天线对木星同步辐射进行了详细的观测。结果表明，在辐射增强过程中，相对论电子具有很强的各向异性。还发现了辐射与太阳10.7通量之间的相关关系。模式模拟表明，观测到的射电通量增强是由于强烈的太阳UV/EUV事件导致的径向扩散增强导致的，该事件加热了木星的上层大气。利用三个航天器的数据研究了木星磁层释放的高能电子的变化。分析证实，木星电子受到木星位置太阳风的动态压力的调制。研究还发现，高能电子的释放率受IMF的极性控制。

1. The receiving system for the observation of Jupiter's synchrotron radiation has been developed. The developed pre-amplifier satisfies the demands of the minimum detection sensitivity of 0.1 Junsky and receiver noise temperature of 75 K.2. The calibration system for the receiver, which is necessary to detect the accurate intensity of Jupiter's radiation, has been developed and completed. The phase and gain of the receiving system becomes to be calibrated using the loop method. The achieved compensation of the relative phase difference was less than 5.6, and relative gain was less than 0.2 dB.3. The developed receiving and calibration system was connected to the large antenna system, and the performance test was carried out. It was confirmed that both the antenna beam width and receiving sensitivity satisfy the expected performance. The distribution map of the Galactic radio waves at a frequency of 327 MHz was successfully produces.4. The simultaneous intensity variation of Jupiter's synchrotron radiation has detected using the radio telescopes of Kiso and Fuji Observatories, Nagoya University.5. Detailed observations of Jovian synchrotron radiation was carried out using the 34 m large dish antenna. It was shown that the relativistic electrons were highly anisotropy during the radiation was enhanced. The correlation between the radiation and the solar 10.7 flux was also detected. A model simulation suggested that the observed radio flux enhancement was caused by the enhanced radial diffusion due to the intense solar UV/EUV event which heated the Jupiter's upper atmosphere.6. Variations of energetic electrons released from the Jovian magnetosphere are investigated by using data from three spacecraft. Analyses confirmed that the Jovian electrons are modulated by the dynamic pressure of the solar wind at the position of Jupiter. It is also found that the release rate of energetic electrons is controlled by the polarity of IMF.