Year: 2026
Type: article
Abstract: Solar wind density fluctuations show typical features of a turbulent energy cascade, including power-law spectra and intermittency. An alternative description in terms of an information cascade and the study of the transition to complexity of the scale-dependent dynamics can provide complementary information on the nonlinear processes governing turbulence. High-resolution proton density measurements from the Spektr-R spacecraft are analyzed using empirical mode decomposition in intrinsic mode functions. The transfer of information and coupling strength between different scales is quantitatively assessed using transfer entropy and mutual information operators. The possible role of intermittency in preventing information from vanishing at proton scales is discussed. In particular, it is demonstrated that in the inertial range it promotes efficient information exchange/coupling, while its absence at kinetic scales constrains the causal transfer to local interactions, only between immediately adjacent scales. The analysis, quantified by the asymmetric flux ratio, confirms that the forward (direct) cascade is the overall dominant causal mechanism across the inertial range. However, the inverse flow becomes locally dominant at kinetic scales.
Source: The Astrophysical Journal
Institutions: National Research Council, Institute of Atmospheric Pollution Research, University of Calabria, Institute for the Science and Technology of Plasmas, KTH Royal Institute of Technology, Osservatorio Astrofisico di Torino, National Institute for Astrophysics, University of Alabama in Huntsville, Queen Mary University of London, Charles University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, UK Research and Innovation, European Commission, Grantová Agentura České Republiky, Vetenskapsrådet, Ministero dell'Università e della Ricerca, Science and Technology Facilities Council, Office of Experimental Program to Stimulate Competitive Research, NextGenerationEU
Awards: G1308404799, G1545804900, Evolution of turbulence in the expanding solar wind, RII Track-1: Future Technologies and Enabling Plasma Processes, G231133531, Where and how the solar wind is accelerated and heated and how these processes affect its evolution?, G3326373620, G4931424118, G6337354726, Heliospheric and Planetary Research 2023-2026, G6793957551, G972786147
OpenAlex ID: W7127614814