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Related papers: Where the granular flows bend

200 papers

Supergranulation is a fluid-dynamical phenomenon taking place in the solar photosphere, primarily detected in the form of a vigorous cellular flow pattern with a typical horizontal scale of approximately 30--35~megameters, a dynamical…

Solar and Stellar Astrophysics · Physics 2018-07-05 Francois Rincon , Michel Rieutord

Granulation in the photospheres of FGK-type stars induces variability in absorption lines, complicating exoplanet detection via radial velocities and characterisation via transmission spectroscopy. We aim to quantify the impact of…

We study the energy flux carried by acoustic waves excited by convective motions at sub-photospheric levels. The analysis of high-resolution spectropolarimetric data taken with IMaX/Sunrise provides a total energy flux of ~ 6400--7700…

In June 2013, the two scientific instruments onboard the second Sunrise mission witnessed, in detail, a small-scale magnetic flux emergence event as part of the birth of an active region. The Imaging Magnetograph Experiment (IMaX) recorded…

In the surface layers of late-type stars, stellar convection is manifested with its typical granulation pattern due to the presence of convective motions. The resulting photospheric up- and downflows leave imprints in the observed spectral…

Solar and Stellar Astrophysics · Physics 2014-05-30 Zazralt Magic , Martin Asplund

Stellar surface magnetoconvection (granulation) creates asymmetries in the observed stellar absorption lines that can subsequently manifest themselves as spurious radial velocities shifts. In turn, this can then mask the Doppler-reflex…

Earth and Planetary Astrophysics · Physics 2019-07-10 H. M. Cegla , C. A. Watson , S. Shelyag , M. Mathioudakis , S. Moutari

Numerical models of solar flares typically focus on the behaviour of directly-heated flare models, adopting magnetic field- aligned, plane-parallel methodologies. With high spatial- and spectral-resolution ground-based optical observations…

Solar and Stellar Astrophysics · Physics 2022-09-21 Christopher M. J. Osborne , Lyndsay Fletcher

Small bipolar magnetic features are observed to appear in the interior of individual granules in the quiet Sun, signaling the emergence of tiny magnetic loops from the solar interior. We study the origin of those features as part of the…

Solar and Stellar Astrophysics · Physics 2018-06-05 F. Moreno-Insertis , J. Martinez-Sykora , V. H. Hansteen , D. Muñoz

The astrophysically very interesting Li I 671 nm line has been observed with high spatial resolution in solar granulation with the intention to diagnose departures from local thermodynamic equilibrium (LTE) in the line formation. The…

Astrophysics · Physics 2007-05-23 Dan Kiselman

Realistic ab-initio 3D, radiative-hydrodynamical convection simulations of the solar granulation have been applied to FeI and FeII line formation. In contrast to classical analyses based on hydrostatic 1D model atmospheres the procedure…

Astrophysics · Physics 2007-05-23 M. Asplund , AA. Nordlund , R. Trampedach , C. Allende Prieto , R. F. Stein

The chromosphere above active regions (ARs) on the Sun hosts magnetized supersonic downflows. Studies of these supersonic downflows help to decipher the magnetic fine structure and dynamics of the chromosphere. We perform a statistical…

Solar and Stellar Astrophysics · Physics 2022-07-26 K. Sowmya , A. Lagg , S. K. Solanki , J. S. Castellanos Durán

Supergranules are convection cells seen at the Sun's surface as a space filling pattern of horizontal flows. While typical supergranules have diameters of about 35 Mm, they exhibit a broad spectrum of sizes from ~10 Mm to ~100 Mm. Here we…

Solar and Stellar Astrophysics · Physics 2015-06-04 David H. Hathaway

Solar granules are bright patterns surrounded by dark channels called intergranular lanes in the solar photosphere and are a manifestation of overshooting convection. Observational studies generally find stronger upflows in granules and…

Solar and Stellar Astrophysics · Physics 2017-11-01 T. Oba , T. L. Riethmüller , S. K. Solanki , Y. Iida , C. Quintero Noda , T. Shimizu

We study the ascent of granular-sized magnetic bubbles from the solar photosphere through the chromosphere into the transition region and above, for the first time. Such events occurred in a flux emerging region in NOAA 11850 on September…

We observe that intergranular jets, originating in the intergranular space surrounding individual granules, tend to be associated with granular fragmentation, in particular, with the formation and evolution of a bright granular lane (BGL)…

Solar and Stellar Astrophysics · Physics 2015-05-28 V. B. Yurchyshyn , P. R. Goode , V. I. Abramenko , O. Steiner

Context. Recent discoveries of intensity correlated downflows in the interior of a sunspot penumbra provide direct evidence for overturning convection, adding to earlier strong indications of convection from filament dynamics observed far…

Solar and Stellar Astrophysics · Physics 2015-05-30 G. B. Scharmer , V. M. J. Henriques

Supergranulation is characterized by horizontally divergent flows with typical length scales of 32 Mm in the solar photosphere. Unlike granulation, the size of which is comparable to both the thickness of the radiative boundary layer and…

Solar and Stellar Astrophysics · Physics 2016-10-05 Jean-Francois Cossette , Mark Peter Rast

The solar photospheric Fe abundance has been determined using realistic ab initio 3D, time-dependent, hydrodynamical model atmospheres. The study is based on the excellent agreement between the predicted and observed line profiles directly…

Astrophysics · Physics 2007-05-23 M. Asplund , AA. Nordlund , R. Trampedach , R. F. Stein

The main small-scale elements observed in the solar photosphere at high resolution are discussed: granules, faculaes, micropores. As a separate element of the fine structure, a continuous network of dark intergranular gaps is considered.…

Solar and Stellar Astrophysics · Physics 2019-11-07 A. A. Soloviev , L. D. Parfinenko , V. I. Efremov , E. A. Kirichek , O. A. Korolkova

We investigated the vertical penumbral plasma flow on small spatial scales using data recorded by the spectropolarimeter of the solar optical telescope onboard Hinode. To this end we computed maps of apparent Doppler velocities by comparing…

Solar and Stellar Astrophysics · Physics 2015-05-14 Morten Franz , Rolf Schlichenmaier