The Oblique Alfvén Ion Beam Instability in the Earth’s Ion Foreshock
The Oblique Alfvén Ion Beam Instability in the Earth’s Ion Foreshock作者机构:Key Laboratory of Planetary SciencesPurple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Hebei Key Laboratory of Compact FusionLangfang 065001China ENN Science and Technology Development Co.Ltd.Langfang065001China
出 版 物:《Research in Astronomy and Astrophysics》 (天文和天体物理学研究(英文版))
年 卷 期:2023年第23卷第2期
页 面:177-186页
核心收录:
学科分类:070802[理学-空间物理学] 07[理学] 0708[理学-地球物理学] 0704[理学-天文学]
基 金:supported by the National Key R&D Program of China 2021YFA1600502(2021YFA1600500) the NSFC 41974203
主 题:plasmas instabilities waves (Sun:)solar terrestrial relations
摘 要:How ions evolve in the Earth’s ion foreshock is a basic problem in the heliosphere community,and the ion beam instability is usually proposed to be one major mechanism affecting the ion dynamics *** work will perform comprehensive analyses of the oblique ion beam instability in the Earth’s ion *** show that in addition to two well-known parallel instabilities (i.e.,the parallel fast-magnetosonic whistler instability and the parallel Alfvén ion cyclotron instability),the oblique Alfvén ion beam (OA/IB) instability can also be triggered by free energy relating to the relative drift d V between the solar wind proton and reflected proton *** slow d V (e.g.,d V■2.2V_(A),where VAdenotes the Alfvén speed),it only triggers the OA/IB *** d V■2.2V_(A),the growth rate in the OA/IB instability can be about 0.6 times the maximum growth rate in parallel ***,this work finds the existence of two types of OA/IB *** first one appears at slow d V and in the small wavenumber region at fast d V,and this instability can be described by the cold fluid *** second one arises in large wavenumber regions at fast d V,and this instability only appears in warm ***,through the energy transfer rate method,we propose that the OA/IB instability is driven by the competition among the Landau and cyclotron wave-particle interactions of beam protons,the cyclotron wave-particle interaction of core protons,and the Landau wave-particle interaction of *** oblique waves can experience significant damping,the importance of the OA/IB instability may be the effective heating of ions in the Earth’s foreshock.