微粒電漿中之磁流體波

Hydromagnetic waves in dusty plasmas

莊師豪(Shih-Hau Chuang)

指導教授 ： 郝玲妮

國立中央大學/地球科學學院/太空科學研究所/碩士(2006年)

摘要

灰塵粒子普遍存在於天文與太空電漿環境中，如土星環。這類灰塵會吸附電荷而形成帶電粒子，其荷質比遠低於一般離子，因此在磁性電漿中，灰塵將有別於離子與電子，而構成第三種磁流體。本論文探討了在灰塵效應下低頻磁流體波的傳播特性。所使用之模式為mobile dust Hall MHD模型以及immobile dust Hall MHD模型。本文將討論此兩種模式下之線性磁流體波的特性，如頻散關係、磁場與密度擾動關係及波的極化情形等。

關鍵字

微粒電漿系統 ； 磁流體波

並列摘要

Dust particles may exist in various space plasma environments such as the Saturn’s rings and they carry mostly negative charges that may depend on both the dust particles and the ambient plasma properties. The charge-to-mass ratios of typical dust grains are generally much smaller than the ordinary ions and electrons and thus form a distinct component in the magnetized plasma. In this study, the effects of dusty particles on the propagation of hydromagnetic waves are examined; in particular, the plasmas under consideration comprise the electrons, ions as well as dusty ions and their dynamics are described by the multi-component hydromagnetic equations. We discuss two different models for dusty plasma systems: immobile dust Hall MHD model and mobile dust Hall MHD model. Using these models, we examine the properties of linear hydromagnetic waves, such as the dispersion relation, the density-magnetic field correlation and the wave polarization etc.

並列關鍵字

dusty plasmas ； MHD wave

參考文獻

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