DETECTION OF COHERENT STRUCTURES IN PHOTOSPHERIC TURBULENT FLOWS

Author(s)

Chian, Abraham C. -L. ^{[1, 2, 3]} ; Rempel, Erico L. ^{[3, 4]} ; Aulanier, Guillaume ^[1] ; Schmieder, Brigitte ^[1] ; Shadden, Shawn C. ^[5] ; Welsch, Brian T. ^[6] ; Yeates, Anthony R. ^[7]

Affiliation

^[1] Observ Paris, CNRS, LESIA, F-92190 Meudon - France

^[2] Univ Adelaide, Sch Math Sci, Adelaide, SA 5005 - Australia

^[3] WISER, Natl Inst Space Res INPE, BR-12227010 Sao Jose Dos Campos, SP - Brazil

^[4] WISER, Inst Aeronaut Technol ITA, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[5] Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 - USA

^[6] Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 - USA

^[7] Univ Durham, Dept Math Sci, Durham DH1 3LE - England

• Document type: Journal article
• Source: ASTROPHYSICAL JOURNAL; v. 786, n. 1 MAY 1 2014.
• Web of Science Citations: 15

Abstract

We study coherent structures in solar photospheric flows in a plage in the vicinity of the active region AR 10930 using the horizontal velocity data derived from Hinode/ Solar Optical Telescope magnetograms. Eulerian and Lagrangian coherent structures (LCSs) are detected by computing the Q-criterion and the finite-time Lyapunov exponents of the velocity field, respectively. Our analysis indicates that, on average, the deformation Eulerian coherent structures dominate over the vortical Eulerian coherent structures in the plage region. We demonstrate the correspondence of the network of high magnetic flux concentration to the attracting Lagrangian coherent structures (aLCSs) in the photospheric velocity based on both observations and numerical simulations. In addition, the computation of aLCS provides a measure of the local rate of contraction/ expansion of the flow. (AU)

• FAPESP's process: 13/22314-7 - Magnetic fields and dynamos in space and astrophysical plasmas II
• Grantee: Erico Luiz Rempel
• Support Opportunities: Regular Research Grants