The structure of magnetic turbulence in the heliosheath region observed by Voyager 2 at 106 AU

Abstract

It is currently believed that the turbulent fluctuations pervade the outermost heliosphere. Turbulence, magnetic reconnection, and their link may be responsible for magnetic energy conversion in these regions. The governing mechanisms of such anisotropic and compressible magnetic turbulence in the inner heliosheath (IHS) and in the local interstellar medium (LISM) still lack a thorough description. The present literature mainly concerns large scales which are not representative of the inertial-cascade dynamics of turbulence. Moreover, lack of broadband spectral analysis makes the IHS dynamics critically understudied. Our recent study shows that 48 s magnetic-field data from the Voyager mission are appropriate for a spectral analysis over a frequency range of six decades, from 5 x 10-8 Hz to 10-2 Hz. Here, focusing on the Voyager 2 observation interval from 2013.824 to 2016.0, we describe the structure of turbulence in a sector zone of the IHS. A spectral break around 7 x 10-7 Hz (magnetic structures with size l~1.3 Astronomical Units) separates the energy-injection regime from the inertial-cascade regime of turbulence. A second scale is observed around 6 x 10-5 Hz (l~ 0.017 AU) and corresponds to a peak of compressibility and intermittency of fluctuations.

arXiv comment10

References in corpus (13)

• Dissipation of the sectored heliospheric magnetic field near the heliopause: a mechanism for the generation of anomalous cosmic rays
• Modeling of the heliospheric interface: multi-component nature of the heliospheric plasma
• Turbulence-driven ion beams in the magnetospheric Kelvin-Helmholtz instability
• Three-dimensional Features of the Outer Heliosphere Due to Coupling between the Interstellar and Heliospheric Magnetic Field. V. The Bow Wave, Heliospheric Boundary Layer, Instabilities, and Magnetic Reconnection
• Heliosheath Processes and the Structure of the Heliopause: Modeling Energetic Particles, Cosmic Rays, and Magnetic Fields
• On the 1/f spectrum in the solar wind and its connection with magnetic compressibility
• Magnetic turbulence spectra and intermittency in the heliosheath and in the local interstellar medium
• Modeling Shocks Detected by Voyager 1 in the Local Interstellar Medium
• Cross and magnetic helicity in the outer heliosphere from Voyager 2 observations
• Pickup Ion Effect of the Solar Wind Interaction with the Local Interstellar Medium
• Voyager 2 solar plasma and magnetic field spectral analysis for intermediate data sparsity
• The formation of magnetic depletions and flux annihilation due to reconnection in the heliosheath
• Turbulence in the solar wind: spectra from Voyager 2 data at 5 AU

Cited by in corpus (1)

• Turbulence in the outer heliosphere