Turbulence in a Coronal Loop Excited by Photospheric Motions

Bibliographic Details
Title: Turbulence in a Coronal Loop Excited by Photospheric Motions
Authors: Giuseppina Nigro, Francesco Malara, Antonio Vecchio, Leonardo Primavera, Francesca Di Mare, Vincenzo Carbone, Pierluigi Veltri
Source: Atmosphere, Vol 11, Iss 4, p 409 (2020)
Publisher Information: MDPI AG, 2020.
Publication Year: 2020
Collection: LCC:Meteorology. Climatology
Subject Terms: solar corona, turbulence, numerical modeling, Meteorology. Climatology, QC851-999
More Details: Photospheric motions are believed to be the source of coronal heating and of velocity fluctuations detected in the solar corona. A numerical model, based on the shell technique applied on reduced magnetohydrodynamics equations, is used to represent energy injection due to footpoint motions, storage and dissipation of energy in a coronal loop. Motions at the loop bases are simulated by random signals whose frequency-wavenumber spectrum reproduces features of photospheric motions: the p-mode peak and the low-frequency continuum. Results indicate that a turbulent state develops, dominated by magnetic energy, where dissipation takes place in an intermittent fashion. The nonlinear cascade is mainly controlled by velocity fluctuations, where resonant modes are dominant at high frequencies. Low frequency fluctuations present a power-law spectra and a bump at p-mode frequency; similar features are observed in velocity spectra detected in the corona. For typical loop parameters the energy input flux is comparable with that necessary to heat the quiet-Sun corona.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2073-4433
Relation: https://www.mdpi.com/2073-4433/11/4/409; https://doaj.org/toc/2073-4433
DOI: 10.3390/atmos11040409
Access URL: https://doaj.org/article/05189026f0e04cfc8c6512dec6dcbe3a
Accession Number: edsdoj.05189026f0e04cfc8c6512dec6dcbe3a
Database: Directory of Open Access Journals
More Details
ISSN:20734433
DOI:10.3390/atmos11040409
Published in:Atmosphere
Language:English