Radial Diffusion Driven by Spatially Localized ULF Waves in the Earth's Magnetosphere

被引：0

作者：

Osmane, Adnane ^{[1
]}

Sandhu, Jasmine K. ^{[2
]}

Elsden, Tom ^{[3
]}

Allanson, Oliver ^{[4
,5
,6
]}

Turc, Lucile ^{[1
]}

机构：

[1] Univ Helsinki, Dept Phys, Helsinki, Finland

[2] Univ Leicester, Dept Phys & Astron, Leicester, England

[3] Univ St Andrews, Sch Math & Stat, St Andrews, Scotland

[4] Univ Birmingham, Sch Engn, Space Environm & Radio Engn, Birmingham, England

[5] Univ Exeter, Dept Earth & Environm Sci, Environm Math, Penryn, England

[6] Univ Exeter, Dept Math, Exeter, England

来源：

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS | 2025年 / 130卷 / 03期

基金：

英国自然环境研究理事会;

关键词：

FIELD LINE RESONANCES; PULSATIONS; ACCELERATION; POWER;

D O I：

10.1029/2024JA033393

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Ultra-Low Frequency (ULF) waves are critical drivers of particle acceleration and loss in the Earth's magnetosphere. While statistical models of ULF-induced radial transport have traditionally assumed that the waves are uniformly distributed across magnetic local time (MLT), decades of observational evidence show significant MLT localization of ULF waves in the Earth's magnetosphere. This study presents, for the first time, a quasi-linear radial diffusion coefficient accounting for localized ULF waves. Our results reveal that when ULF waves cover more than 30% of the MLT, the radial diffusion efficiency is comparable to that of uniform wave distributions. However, when ULF waves are confined within 10% of the drift orbit, the transport coefficient is enhanced by 10%-25%, indicating that narrowly localized ULF waves are efficient drivers of radial diffusion.

引用

页数：14

共 51 条

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