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Abstract We explore the characteristics of EMIC waves generated in a non‐dipole, compressed magnetic field at the minimum of the magnetic field. We conducted 2D full‐wave simulations using the Petra‐M code, focusing on a compressed magnetic field in the outer dayside magnetosphere for a range ofLvalues . By comparing the simulation results with MMS observations, we aim to understand how the observed wave characteristics are affected by a shifting source region across different L‐shells. Our findings indicate that the direction of the Poynting vector systematically changes depending on the local source location of the wave, which is consistent with the observations. EMIC waves propagate along the magnetic field line and reach both the northern and southern hemispheres; however, there is a notable difference in the power of EMIC waves between the two hemispheres, indicating seasonal asymmetries in their occurrence.
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Applications of the Petra-M simulation code for the magnetospheric physics
We present applications of the full-wave solver, Petra-M code for Earth magnetospheric plasma wave physics by leveraging the current effort of the radio frequency wave project. Because the Petra-M code uses the modular finite element method (MFEM) library, the boundary shapes, plasma density profiles, and realistic planetary magnetic fields can be easily adapted. In order to incorporate realistic Earth’s magnetic field into the Petra-M, we utilize the self-consistent magnetospheric flux models for compressed and stretched magnetic fields and realistic magnetospheric magnetic field geometries extracted from global MHD simulations. Using Petra-M code, we then examine ultra-low frequency (ULF) wave propagations in various magnetic field shapes. For example, left-handed polarized electromagnetic ion cyclotron waves in Earth’s dipole and compressed magnetic field are examined to consider waves in the inner and dayside outer magnetospheres, respectively. Mode-converted Alfvén wave propagation is also demonstrated in the compressed (dayside), stretched(nightside), and realistically stretched magnetic field (magnetotail). Therefore, the Petra-M code successfully demonstrates magnetospheric plasma wave propagation despite the spatial scale differences between the fusion devices (~m) and Earth’s magnetosphere (103 − 104km).
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- Award ID(s):
- 2131013
- PAR ID:
- 10531412
- Publisher / Repository:
- AIP Publishing
- Date Published:
- ISSN:
- 1551-7616
- Subject(s) / Keyword(s):
- Ultra low frequency, Magnetospheric physics, Outer magnetosphere, Planetary magnetic fields, Finite-element analysis, Fusion reactors, Cyclotrons, Libraries, Magnetospheric plasmas, Plasma properties and parameters
- Format(s):
- Medium: X
- Location:
- Annapolis, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.1063/5.0164070
