Two-Dimensional gcPIC Simulation of Rising-Tone Chorus Waves in a Dipole Magneitic Field

Lu, Quanming1,2; Ke, Yangguang1,2; Wang, Xueyi3; Liu, Kaijun4; Gao, Xinliang1,2; Chens, Lunjin5; Wang, Shui1,2

2019-06

10.1029/2019JA026586

JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS   影响因子和分区

2169-9380

2169-9402

Rising-tone chorus waves have already been successfully produced in a mirror magnetic field with the use of one- and two-dimensional particle-in-cell (PIC) simulations. However, in reality, the background magnetic field in the inner Earth's magnetosphere is a dipole magnetic field, unlike symmetric mirror fields. In this paper, with the two-dimensional (2-D) general curvilinear PIC (gcPIC) code, we investigate the generation of rising-tone chorus waves in the dipole magnetic field configuration. The plasma consists of three components: immobile ions, cold background, and hot electrons. In order to save computational resource, the topology of the magnetic field is roughly equal to that at L = 0.6 R-E, although the plasma parameters corresponding to those at L = 6 R-E (R-E is the Earth's radius) are used. Whistler mode waves are first excited around the magnetic equator by the hot electrons with a temperature anisotropy. The excited whistler mode waves propagate almost parallel and antiparallel to the background magnetic field in their source region, which is limited at vertical bar lambda vertical bar <= 3 degrees (where lambda is the magnetic latitude). When the waves leave from the source region and propagate toward high latitudes, both their amplitude and wave normal angle become larger. However, the group velocity of the waves is directed toward high latitudes almost along the magnetic field. During such a process, the waves have a frequency chirping, as shown by a rising tone in the frequency-time spectrogram. To our best knowledge, it is for the first time that rising-tone chorus are generated in a dipole magnetic field with a PIC simulation.

SCI

英语

其他

Youth Innovation Promotion Association of Chinese Academy of Sciences[2016395]

Astronomy & Astrophysics

Astronomy & Astrophysics

WOS:000477723100021

AMER GEOPHYSICAL UNION

SPACE SCIENCE

Web of Science

1.Univ Sci & Technol China, Dept Geophys & Planetary Sci, CAS Key Lab Geospace Environm, Hefei, Anhui, Peoples R China
2.CAS Ctr Excellence Comparat Planetol, Hefei, Anhui, Peoples R China
3.Auburn Univ, Dept Phys, Auburn, AL 36849 USA
4.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen, Peoples R China
5.Univ Texas Dallas, Dept Phys, Richardson, TX 75083 USA

Lu, Quanming,Ke, Yangguang,Wang, Xueyi,et al. Two-Dimensional gcPIC Simulation of Rising-Tone Chorus Waves in a Dipole Magneitic Field[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS,2019,124(6):4157-4167.

Lu, Quanming.,Ke, Yangguang.,Wang, Xueyi.,Liu, Kaijun.,Gao, Xinliang.,...&Wang, Shui.(2019).Two-Dimensional gcPIC Simulation of Rising-Tone Chorus Waves in a Dipole Magneitic Field.JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS,124(6),4157-4167.

Lu, Quanming,et al."Two-Dimensional gcPIC Simulation of Rising-Tone Chorus Waves in a Dipole Magneitic Field".JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS 124.6(2019):4157-4167.