# 3D Magnetic Holes in Collisionless Plasmas

## Abstract

Recent multispacecraft observations in the Earth’s magnetosphere have revealed an abundance of magnetic holes—localized magnetic field depressions. These magnetic holes are characterized by the plasma pressure enhancement and strongly localized currents flowing around the hole boundaries. There are several numerical and analytical models describing 2D configurations of magnetic holes, but the 3D distribution of magnetic fields and electric currents is studied poorly. Such a 3D magnetic field configuration is important for accurate investigation of charged particle dynamics within magnetic holes. Moreover, the 3D distribution of currents can be used for distant probing of magnetic holes in the magnetosphere. In this study, a 3D magnetic hole model using the single-fluid approximation and a spatial scale hierarchy with the distinct separation of gradients is developed. It is shown that such 3D holes can be obtained as a generalization of 1D models with the plasma pressure distribution adopted from the kinetic approach. The proposed model contains two magnetic field components and field-aligned currents. The magnetic field line configuration resembles the magnetic trap where hot charged particles bounce between mirror points. However, the approximation of isotropic pressure results in a constant plasma pressure along magnetic field lines, and the proposed magnetic hole model doesmore »

- Authors:

- Russian Academy of Sciences, Space Research Institute (Russian Federation)
- Moscow State University, Department of Physics (Russian Federation)

- Publication Date:

- OSTI Identifier:
- 22763239

- Resource Type:
- Journal Article

- Journal Name:
- Plasma Physics Reports

- Additional Journal Information:
- Journal Volume: 44; Journal Issue: 8; Other Information: Copyright (c) 2018 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1063-780X

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; APPROXIMATIONS; CHARGED PARTICLES; COLLISIONLESS PLASMA; ELECTRIC CURRENTS; MAGNETIC FIELD CONFIGURATIONS; MAGNETIC FIELDS; PLASMA PRESSURE

### Citation Formats

```
Shustov, P., E-mail: p.shustov@gmail.ru, Artemyev, A., Yushkov, E., and Vasko, I.
```*3D Magnetic Holes in Collisionless Plasmas*. United States: N. p., 2018.
Web. doi:10.1134/S1063780X18080068.

```
Shustov, P., E-mail: p.shustov@gmail.ru, Artemyev, A., Yushkov, E., & Vasko, I.
```*3D Magnetic Holes in Collisionless Plasmas*. United States. doi:10.1134/S1063780X18080068.

```
Shustov, P., E-mail: p.shustov@gmail.ru, Artemyev, A., Yushkov, E., and Vasko, I. Wed .
"3D Magnetic Holes in Collisionless Plasmas". United States. doi:10.1134/S1063780X18080068.
```

```
@article{osti_22763239,
```

title = {3D Magnetic Holes in Collisionless Plasmas},

author = {Shustov, P., E-mail: p.shustov@gmail.ru and Artemyev, A. and Yushkov, E. and Vasko, I.},

abstractNote = {Recent multispacecraft observations in the Earth’s magnetosphere have revealed an abundance of magnetic holes—localized magnetic field depressions. These magnetic holes are characterized by the plasma pressure enhancement and strongly localized currents flowing around the hole boundaries. There are several numerical and analytical models describing 2D configurations of magnetic holes, but the 3D distribution of magnetic fields and electric currents is studied poorly. Such a 3D magnetic field configuration is important for accurate investigation of charged particle dynamics within magnetic holes. Moreover, the 3D distribution of currents can be used for distant probing of magnetic holes in the magnetosphere. In this study, a 3D magnetic hole model using the single-fluid approximation and a spatial scale hierarchy with the distinct separation of gradients is developed. It is shown that such 3D holes can be obtained as a generalization of 1D models with the plasma pressure distribution adopted from the kinetic approach. The proposed model contains two magnetic field components and field-aligned currents. The magnetic field line configuration resembles the magnetic trap where hot charged particles bounce between mirror points. However, the approximation of isotropic pressure results in a constant plasma pressure along magnetic field lines, and the proposed magnetic hole model does not confine plasma along the field direction.},

doi = {10.1134/S1063780X18080068},

journal = {Plasma Physics Reports},

issn = {1063-780X},

number = 8,

volume = 44,

place = {United States},

year = {2018},

month = {8}

}