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Related papers: Vorticity in the solar photosphere

200 papers

Theories, simulations and experiments on vortex dynamics in quasi-two-dimensional magnetic materials are reviewed. These materials can be modelled by the classical two-dimensional anisotropic Heisenberg model with XY (easy-plane) symmetry.…

Condensed Matter · Physics 2007-05-23 F. G. Mertens , A. R. Bishop

We find an instability resulting in generation of large-scale vorticity in a fast rotating small-scale turbulence or turbulent convection with inhomogeneous fluid density along the rotational axis in anelastic approximation. The large-scale…

Fluid Dynamics · Physics 2019-12-11 Igor Rogachevskii , Nathan Kleeorin

We use a vortex retarder-based approach to generate few optical cycles light pulses carrying orbital angular momentum (known also as twisted light or optical vortex) from a Yb:KGW oscillator pumping a noncollinear optical parametric…

Massive star winds are important contributors to the energy, momentum and chemical enrichment of the interstellar medium. Strong, organized and predominantly dipolar magnetic fields have been firmly detected in a small subset of massive…

Solar and Stellar Astrophysics · Physics 2020-04-29 Melissa Munoz , Gregg Wade , Daniel Faes , Alex Carciofi

We study all the possibilities of producing rotating flow in an incompressible fluid by electric and magnetic fields. We start with a general theoretical basis and look for different configurations and set-ups which electric/magnetic field…

Fluid Dynamics · Physics 2013-03-25 A. Amjadi , A. Nejati , S. O. Sobhani , R. Shirsavar

Context. We consider a localized pulse in the component of velocity, parallel to the ambient magnetic field lines, that is initially launched in the solar chromosphere. Aims. We aim to generalize the recent numerical model of spicule…

Solar and Stellar Astrophysics · Physics 2015-05-30 K. Murawski , Abhishek K. Srivastava , T. V. Zaqarashvili

The work is devoted to the study of periodic structures in the magnetic field of the photosphere. The polarity of the Sun's magnetic fields shows cyclicity with periods of 1-3 years, which is possibly due to quasi-biennial variations that…

Solar and Stellar Astrophysics · Physics 2025-07-08 Elena Vernova , Marta Tyasto , Dmitrii Baranov

We assemble a homogeneous database of precise and consistent determinations of effective temperature, surface gravity, projected rotational rate, and macro- and micro-turbulent velocities for over 1800 Galactic stars spanning spectral types…

Solar and Stellar Astrophysics · Physics 2025-10-01 N. Markova , M. Cantiello , L. Grassitelli

Generation of few-cycle optical vortex pulses is challenging due to the large spectral bandwidths, as most vortex generation techniques are designed for monochromatic light. In this work, we use a spiral phase plate to generate few-cycle…

Using high-resolution spectropolarimetric data recorded with the Swedish 1 m Solar Telescope, we have identified several instances of granular lanes traveling into granules. These are believed to be the observational signature of underlying…

Solar and Stellar Astrophysics · Physics 2020-11-11 C. E. Fischer , G. Vigeesh , P. Lindner , J. M. Borrero , F. Calvo , O. Steiner

Observations of the solar atmosphere show that internal gravity waves are generated by overshooting convection, but are suppressed at locations of magnetic flux, which is thought to be the result of mode conversion into magneto-acoustic…

Solar and Stellar Astrophysics · Physics 2017-02-01 G. Vigeesh , J. Jackiewicz , O. Steiner

The expansion of the rotating fluid will change the vorticity and rotational speed of the expanding region. In turbulent thermal convection, this microscopic effect is preserved. Tracking the fluid micelles shows that the average vorticity…

Solar and Stellar Astrophysics · Physics 2023-01-03 Haibin Chen , Rong Wu

Numerical MHD simulations play increasingly important role for understanding mechanisms of stellar magnetism. We present simulations of convection and dynamos in density-stratified rotating spherical fluid shells. We employ a new 3D…

Solar and Stellar Astrophysics · Physics 2015-09-03 Radostin D. Simitev , Alexander G. Kosovichev , Friedrich H. Busse

We study the structure and reveal the physical nature of the reversed granulation pattern in the solar photosphere by means of 3-dimensional radiative hydrodynamics simulations. We used the MURaM code to obtain a realistic model of the…

Astrophysics · Physics 2009-11-11 M. C. C. Cheung , M. Schuessler , F. Moreno-Insertis

Recent analysis of the helioseismic observations indicate that the previously observed surface torsional oscillations extend significantly downwards into the solar convection zone. In an attempt to understand these oscillations, we study…

Astrophysics · Physics 2007-05-23 Eurico Covas , Reza Tavakol , David Moss , Andrew Tworkowski

Using the 135-second cadence of the photospheric vector data provided by the Helioseismic and Magnetic Imager telescope on board the Solar Dynamic Observatory, we examined the time-evolution of magnetic helicity fluxes across the…

Solar and Stellar Astrophysics · Physics 2018-10-17 Yi Bi , Ying D Liu , Yanxiao Liu , Jiayan Yang , Zhe Xu , Kaifan JI

The origin of large magnetic fields in the Universe remains currently unknown. We investigate here a mechanism before recombination based on known physics. The source of the vorticity is due to the changes in the photon distribution…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Ophélia Fabre , S. Shankaranarayanan

Solar vortex regions show enhanced Poynting flux and favourable heating conditions, but how the vortices reorganize and influence their surroundings remains unclear. Here we apply information-theoretic diagnostics to a Bifrost simulation to…

Solar and Stellar Astrophysics · Physics 2025-11-21 Suzana S. A. Silva , Erico Rempel , Gary Verth , Istvan Ballai , Viktor Fedun

We derive formulae connecting the frequency variations in the spectrum of solar oscillations to the dynamical quantities that are expected to change over the solar activity cycle. This is done for both centroids and the asymmetric part of…

Astrophysics · Physics 2009-11-10 W. A. Dziembowski , P. R. Goode

We propose a useful method for mapping large-scale velocity fields in the solar photosphere. It is based on the local correlation tracking algorithm when tracing supergranules in full-disc dopplergrams. The method was developed using…

Astrophysics · Physics 2007-05-23 M. Svanda , M. Klvana , M. Sobotka
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