@Article{MirandaRempChia:2015:OnInAm,
author = "Miranda, R. A. and Rempel, Erico Luiz and Chian, Abraham Chian
Long",
affiliation = "{} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)}",
title = "On–off intermittency and amplitude-phase synchronization in
Keplerian shear flows",
journal = "Monthly Notices of the Royal Astronomical Society",
year = "2015",
volume = "448",
number = "1",
pages = "804--813",
month = "Mar.",
keywords = "accretion, accretion discs, MHD, turbulence, methods:
statistical.",
abstract = "We study the development of coherent structures in local
simulations of the magnetorotational instability in accretion
discs in regimes of on-off intermittency. In a previous paper, we
have shown that the laminar and bursty states due to the on-off
spatiotemporal intermittency in a one-dimensional model of
non-linear waves correspond, respectively, to non-attracting
coherent structures with higher and lower degrees of
amplitude-phase synchronization. In this paper, we extend these
results to a three-dimensional model of magnetized Keplerian shear
flows. Keeping the kinetic Reynolds number and the magnetic
Prandtl number fixed, we investigate two different intermittent
regimes by varying the plasma beta parameter. The first regime is
characterized by turbulent patterns interrupted by the recurrent
emergence of a large-scale coherent structure known as two-channel
flow, where the state of the system can be described by a single
Fourier mode. The second regime is dominated by the turbulence
with sporadic emergence of coherent structures with shapes that
are reminiscent of a perturbed channel flow. By computing the
Fourier power and phase spectral entropies in three dimensions, we
show that the large-scale coherent structures are characterized by
a high degree of amplitude-phase synchronization.",
doi = "10.1093/mnras/stu2682",
url = "http://dx.doi.org/10.1093/mnras/stu2682",
issn = "0035-8711 and 1365-2966",
language = "en",
urlaccessdate = "19 abr. 2024"
}