Zhoufan Mu, Yao Chen, Tangmu Li, Sulan Ni, Zilong Zhang, Hao Ning
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引用次数: 0
Abstract
The Z-to-O mode conversion at the density gradient is the prevailing mechanism of narrowband (NB) radio emission in planetary magnetosphere. Most previous numerical models were for NB emission observed in the Earth magnetosphere, using the cold plasma fluid approximation that excluded any kinetic effect. Here we investigate the Z-to-O conversion process underlying the Saturn's 20 kHz NB emission, using the fully kinetic and electromagnetic particle-in-cell (PIC) simulation. We simulate the whole process starting from the pumping of the Z mode, to its propagation and reflection, and further conversion into the O mode radiation. The energy conversion rate of the Z-to-O process is estimated to be 10%–20%. This provides the first quantitative estimate of such rate with PIC simulations.
期刊介绍:
The Journal of Geophysical Research Planets is dedicated to the publication of new and original research in the broad field of planetary science. Manuscripts concerning planetary geology, geophysics, geochemistry, atmospheres, and dynamics are appropriate for the journal when they increase knowledge about the processes that affect Solar System objects. Manuscripts concerning other planetary systems, exoplanets or Earth are welcome when presented in a comparative planetology perspective. Studies in the field of astrobiology will be considered when they have immediate consequences for the interpretation of planetary data. JGR: Planets does not publish manuscripts that deal with future missions and instrumentation, nor those that are primarily of an engineering interest. Instrument, calibration or data processing papers may be appropriate for the journal, but only when accompanied by scientific analysis and interpretation that increases understanding of the studied object. A manuscript that describes a new method or technique would be acceptable for JGR: Planets if it contained new and relevant scientific results obtained using the method. Review articles are generally not appropriate for JGR: Planets, but they may be considered if they form an integral part of a special issue.