| Autor: |
Ballerini, Giulio, Belmont, Gerard, Rezeau, Laurence, Califano, Francesco |
| Rok vydání: |
2023 |
| Předmět: |
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| DOI: |
10.48550/arxiv.2303.14209 |
| Popis: |
Is the magnetosphere closed or open? This is one of the oldest questions in space physics still at the basis of the hottest topics in the field today. With respect to the magnetopause boundary, this translates into: "is this boundary a tangential discontinuity or not?". We revisit this question, and show that the small thickness of the magnetopause escapes classic theory, from which comes the notion of tangential discontinuity. For such "quasi-tangential" discontinuities, both compressive and rotational properties coexist as observed, without requiring strictly null normal fluxes, while they are mutually exclusive when Finite Larmor radius effects are ignored. This change is similar to the change from a shear Alfven wave to a Kinetic Alfven wave for linear modes. We present a typical example of MMS data from a magnetopause crossing. We show that the non-gyrotropic pressure tensor does indeed play a very important role in the boundary equilibrium. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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