Imai Masafumi, Greathouse Thomas K, Kurth William S, Gladstone G Randall, Louis Corentin K, Zarka Philippe, Bolton Scott J, Connerney John E P
Department of Physics and Astronomy University of Iowa Iowa City IA USA.
Space Science and Engineering Division Southwest Research Institute San Antonio TX USA.
Geophys Res Lett. 2019 Jan 28;46(2):571-579. doi: 10.1029/2018GL081227. Epub 2019 Jan 24.
Observations of Jovian broadband kilometric (bKOM) radiation and ultraviolet (UV) auroras were acquired with the Waves and Juno-UVS instruments for ∼2 hr over the northern and southern polar regions during Juno's perijoves 4, 5, and 6 passes (PJ4, PJ5, and PJ6). During all six time periods, Juno traversed auroral magnetic field lines connecting to the UV main auroral ovals, matching the estimates of bKOM radio source footprints. The localized bKOM radio sources for the PJ4 north pass map to magnetic field lines having distances of 10 to 12 Jovian radii (R ) at the magnetic equator, whereas the extended bKOM radio sources for the other events map to field lines extending to 20-61 R . We found the peak bKOM intensities during Juno's potential radio source crossings show positive, negative, and no correlations with the UV main oval brightness and color ratio. Only the positive correlations suggest wave-particle energy transport.
在朱诺号第4、5和6次近木点飞越(PJ4、PJ5和PJ6)期间,利用“波动”(Waves)仪器和“朱诺-紫外分光仪”(Juno-UVS)在南北极地区进行了约2小时的木星宽带千米波辐射(bKOM)和紫外极光观测。在所有六个时间段内,朱诺号穿过了连接到紫外主要极光卵的极光磁力线,与bKOM射电源足迹的估计值相符。PJ4北行的局部bKOM射电源映射到磁赤道处距离为10至12个木星半径(R)的磁力线,而其他事件的扩展bKOM射电源映射到延伸至20 - 61R的磁力线。我们发现,在朱诺号穿过潜在射电源期间,bKOM强度峰值与紫外主要极光卵的亮度和颜色比呈现正相关、负相关以及无相关性。只有正相关表明了波粒能量传输。