English
Related papers

Related papers: Global shallow water magnetohydrodynamic waves in …

200 papers

The influence of a toroidal magnetic field on the dynamics of shallow water waves in the solar tachocline is studied. A sub-adiabatic temperature gradient in the upper overshoot layer of the tachocline causes significant reduction of…

Solar and Stellar Astrophysics · Physics 2018-04-09 T. V. Zaqarashvili

Rapidly rotating stars show short-period oscillations in magnetic activity and polar appearance of starspots. The aim of this paper is to study large-scale shallow water waves in the tachoclines of rapidly rotating stars and their…

Solar and Stellar Astrophysics · Physics 2015-05-28 T. V. Zaqarashvili , R. Oliver , J. L. Ballester , M. Carbonell , M. L. Khodachenko , H. Lammer , M. Leitzinger , P. Odert

The influence of a toroidal magnetic field on the dynamics of Rossby waves in a thin layer of ideal conductive fluid on a rotating sphere is studied in the "shallow water" magnetohydrodynamic approximation for the first time. Dispersion…

Astrophysics · Physics 2009-11-13 T. V. Zaqarashvili , R. Oliver , J. L. Ballester , B. M. Shergelashvili

The activity of Sun-like stars is governed by the magnetic field, which is believed to be generated in a thin layer between convective and radiative envelopes. The dynamo layer, also called the tachocline, permits the existence of Rossby…

Solar and Stellar Astrophysics · Physics 2025-10-13 T. V. Zaqarashvili , M. Dikpati , P. A. Gilman

Can atmospheric waves in planet-hosting solar-like stars substantially resonate to tidal forcing? Substantially at a level of impacting the space weather or even of being dynamo-relevant? In particular, low-frequency Rossby waves, which…

Solar and Stellar Astrophysics · Physics 2023-02-22 G. M. Horstmann , G. Mamatsashvili , A. Giesecke , T. V. Zaqarashvili , F. Stefani

Apart from the 11-year solar cycle, another periodicity around 155-160 days was discovered during solar cycle 21 in high energy solar flares, and its presence in sunspot areas and strong magnetic flux has been also reported. This…

Solar and Stellar Astrophysics · Physics 2014-11-20 T. V. Zaqarashvili , M. Carbonell , R. Oliver , J. L. Ballster

This article deals with rotating magnetohydrodynamic flows of a thin stratified layer of astrophysical plasma in a gravitational field with a free-surface in a vertical external magnetic field. Magnetohydrodynamic equations are obtained in…

Plasma Physics · Physics 2019-07-02 Maria Fedotova , Dmitry Klimachkov , Arakel Petrosyan

In this paper, we have studied the convectively coupled equatorially trapped waves in rotating stars, with and without magnetic field. The equatorial trapped HD and MHD Poincar\'e, Rossby, mixed Rossby-Poincar\'e, and Kelvin waves were…

Solar and Stellar Astrophysics · Physics 2021-10-01 Tao Cai , Cong Yu , Xing Wei

In this work we study oceanic waves in a shallow water flow subject to strong wind forcing and rotation, and linearized around a inhomogeneous (non zonal) stationary profile. This extends the study \cite{CGPS}, where the profile was assumed…

Analysis of PDEs · Mathematics 2010-11-22 Isabelle Gallagher , Thierry Paul , Laure Saint-Raymond

We study the properties of plasma oscillations in the solar tachocline using shallow-water magnetohydrodynamic equations. These oscillations are expected to correlate with solar activity. We find new qualitative features in the equatorial…

Solar and Stellar Astrophysics · Physics 2024-01-17 Ruben Lier , Richard Green , Jan de Boer , Jay Armas

Long-term records of sunspot number and concentrations of cosmogenic radionuclides (10Be and 14C) on the Earth reveal the variation of the Sun's magnetic activity over hundreds and thousands of years. We identify several clear periods in…

Solar and Stellar Astrophysics · Physics 2015-06-03 T. V. Zaqarashvili , R. Oliver , A. Hanslmeier , M. Carbonell , J. L. Ballester , T. Gachechiladze , I. G. Usoskin

We explore how thermal Rossby waves propagate within the gravitationally stratified atmosphere of a low-mass star with an outer convective envelope. Under the conditions of slow, rotationally constrained dynamics, we derive a local…

Solar and Stellar Astrophysics · Physics 2023-09-11 Bradley W. Hindman , Rekha Jain

Annual oscillations have been detected in many indices of solar activity during many cycles. Recent multi spacecraft observations of coronal bright points revealed slow retrograde toroidal phase drift (with the speed of 3 m/s of 1 yr…

We present a linear analysis of inviscid, incompressible, magnetohydrodynamic (MHD) shallow water systems. In spherical geometry, a generic property of such systems is the existence of five wave modes. Three of them (two magneto-Poincare…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Kevin Heng , Anatoly Spitkovsky

Rather weak fossil magnetic fields in the radiative core can produce the solar tachocline if the field is poloidal and almost horizontal in the tachocline region, i.e. if the field is confined within the core. This particular field geometry…

Astrophysics · Physics 2008-11-26 G. Ruediger , L. L. Kitchatinov

In this work we prove that the shallow water flow, subject to strong wind forcing and linearized around an adequate stationary profile, develops for large times closed trajectories due to the propagation of Rossby waves, while Poincar\'e…

Analysis of PDEs · Mathematics 2019-12-19 Christophe Cheverry , Isabelle Gallagher , Thierry Paul , Laure Saint-Raymond

Quasi-biennial oscillations (QBO) are frequently observed in the solar activity indices. However, no clear physical mechanism for the observed variations has been suggested so far. Here we study the stability of magnetic Rossby waves in the…

Solar and Stellar Astrophysics · Physics 2015-05-20 T. V. Zaqarashvili , M. carbonell , R. Oliver , J. L. Ballester

To understand magnetic diffusion, momentum transport, and mixing in the interior of the sun, we consider an idealized model of the tachocline, namely magnetohydrodynamics (MHD) turbulence on a $\beta$ plane subject to a large scale shear…

Astrophysics · Physics 2011-02-11 Nicolas Leprovost , Eun-Jin Kim

Within the framework of shallow-water magnetohydrodynamics, we investigate the linear instability of horizontal shear flows, influenced by an aligned magnetic field and stratification. Various classical instability results, such as…

Fluid Dynamics · Physics 2016-01-15 Julian Mak , Stephen D. Griffiths , D. W. Hughes

Observations by recent space missions reported the detection of Rossby waves (r-modes) in light curves of many stars (mostly A, B, and F spectral types) with outer radiative envelope. This paper aims to study the theoretical dynamics of…

Solar and Stellar Astrophysics · Physics 2023-09-20 M. Albekioni , T. V. Zaqarashvili , V. Kukhianidze , E. Gurgenashvili , P. Bourdin
‹ Prev 1 2 3 10 Next ›