Energy Transfer, Discontinuities, and Heating in the Inner Heliosphere Measured with a Weak and Local Formulation of the Politano–Pouquet Law - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue The Astrophysical Journal Année : 2022

Energy Transfer, Discontinuities, and Heating in the Inner Heliosphere Measured with a Weak and Local Formulation of the Politano–Pouquet Law

Résumé

Abstract The solar wind is a highly turbulent plasma for which the mean rate of energy transfer ε has been measured for a long time using the Politano–Pouquet (PP98) exact law. However, this law assumes statistical homogeneity that can be violated by the presence of discontinuities. Here, we introduce a new method based on the inertial dissipation  I σ whose analytical form is derived from incompressible magnetohydrodynamics; it can be considered as a weak and local (in space) formulation of the PP98 law whose expression is recovered after integration in space. We used  I σ to estimate the local energy transfer rate at scale σ from the THEMIS-B and Parker Solar Probe data taken in the solar wind at different heliospheric distances. Our study reveals that discontinuities near the Sun lead to a strong energy transfer that affects a wide range of scales σ . We also observe that switchbacks seem to be characterized by a singular behavior with an energy transfer varying as σ −3/4 , which slightly differs from classical discontinuities characterized by a σ −1 scaling. A comparison between the measurements of ε and  I σ shows that in general the latter is significantly larger than the former.
Fichier principal
Vignette du fichier
SWobs_David_ApJ_2022.pdf (2.38 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-03644856 , version 1 (19-04-2022)

Identifiants

Citer

V. David, S. Galtier, Fouad Sahraoui, L. Z. Hadid. Energy Transfer, Discontinuities, and Heating in the Inner Heliosphere Measured with a Weak and Local Formulation of the Politano–Pouquet Law. The Astrophysical Journal, 2022, 927 (2), pp.200. ⟨10.3847/1538-4357/ac524b⟩. ⟨hal-03644856⟩
86 Consultations
32 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More