English
Related papers

Related papers: An Average Supergranule: Much Larger Vertical Flow…

200 papers

Surface granulation of the Sun is primarily a consequence of thermal transport in the outer 1 % of the radius. Its typical scale of about 1 - 2 Mm is set by the balance between convection, free-streaming radiation, and the strong density…

Solar and Stellar Astrophysics · Physics 2015-06-18 Shravan M. Hanasoge , Katepalli R. Sreenivasan

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

As large--distance rays (say, 10\,-\,$24 ^\circ$) approach the solar surface approximately vertically, travel times measured from surface pairs for these large separations are mostly sensitive to vertical flows, at least for shallow flows…

Solar and Stellar Astrophysics · Physics 2015-06-05 Thomas L. Duvall, , Shravan M. Hanasoge

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

I analyse the maps recording the travel-time shifts caused by averaged plasma anomalies under an "average supergranule", constructed by means of statistical averaging over 5582 individual supergranules with large divergence signals detected…

Solar and Stellar Astrophysics · Physics 2015-06-11 Michal Svanda

In the recent papers, we introduced a method utilised to measure the flow field. The method is based on the tracking of supergranular structures. We did not precisely know, whether its results represent the flow field in the photosphere or…

Context: Supergranulation is a pattern of the velocity field at the surface of the Sun, which has been known about for more than fifty years, however, no satisfactory explanation of its origin has been proposed. Aims: New observational…

The global scales of solar convection are studied through three-dimensional simulations of compressible convection carried out in spherical shells of rotating fluid which extend from the base of the convection zone to within 15 Mm of the…

Astrophysics · Physics 2009-11-13 Mark S. Miesch , Allan Sacha Brun , Marc L. Derosa , Juri Toomre

Supergranules create a peak in the spatial spectrum of photospheric velocity features. They have some properties of convection cells but their origin is still being debated in the literature. The time-distance helioseismology constitutes a…

Solar and Stellar Astrophysics · Physics 2021-02-24 David Korda , Michal Švanda

Supergranulation on the surface of the Sun is an organized cellular flow pattern with a characteristic scale of 30 Mm. It is superficially similar to the well understood granulation that operates at the 1.5 Mm natural scale of convection,…

Astrophysics · Physics 2009-11-07 L. Gizon , T. L. Duvall , J. Schou

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 Sun provides us with the only spatially well-resolved astrophysical example of turbulent thermal convection. While various aspects of solar photospheric turbulence, such as granulation (one-Megameter horizontal scale), are well…

Solar and Stellar Astrophysics · Physics 2017-03-14 F. Rincon , T. Roudier , A. A. Schekochihin , M. Rieutord

Observations of the solar surface reveal the presence of flows with length scales of around $35$ Mm, commonly referred to as supergranules. Inferring the sub-surface flow profile of supergranules from measurements of the surface and…

Solar and Stellar Astrophysics · Physics 2016-08-03 Jishnu Bhattacharya , Shravan M. Hanasoge

The subsurface structure of an "average" supergranule is derived from existing HMI pipeline time-distance data products and compared to the best helioseismic flow model detailed in Duvall and Hanasoge (2013). We find that significant…

Solar and Stellar Astrophysics · Physics 2015-06-03 K. DeGrave , J. Jackiewicz

Below the scale of supergranules we find that cellular flows are present in the solar photosphere at two distinct size scales, approximately 2 Mm and 4 Mm, with distinct characteristic times. Simultaneously present in the flow is a…

Astrophysics · Physics 2015-06-24 J. K. Lawrence , A. C. Cadavid , A. Ruzmaikin

Solar supergranulation presents us with many mysteries. For example, previous studies in spectral space found that supergranulation has wave-like properties. Here we study, in real space, the wave-like evolution of the average supergranule…

Solar and Stellar Astrophysics · Physics 2018-10-03 J. Langfellner , A. C. Birch , L. Gizon

Supergranules are divergent 30-Mm sized cellular flows observed everywhere at the solar photosphere. Their place in the hierarchy of convective structures and their origin remain poorly understood (Rincon et al., 2018). Estimating…

Solar and Stellar Astrophysics · Physics 2019-10-09 Vedant Dhruv , Jishnu Bhattacharya , Shravan Hanasoge

Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ~3-4% of the solar surface at any time, but these flows have not been detected unambigously as yet. Using data from the spectropolarimeter…

Solar and Stellar Astrophysics · Physics 2009-07-22 L. R. Bellot Rubio

We use subsurface-flow velocity maps inferred by time--distance helioseismology from Doppler measurements with the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory (SDO) to investigate variations of large-scale…

Solar and Stellar Astrophysics · Physics 2025-10-01 Alexander V. Getling , Alexander G. Kosovichev

Flow vorticity is a fundamental property of turbulent convection in rotating systems. Solar supergranules exhibit a preferred sense of rotation, which depends on the hemisphere. This is due to the Coriolis force acting on the diverging…

Solar and Stellar Astrophysics · Physics 2015-09-09 J. Langfellner , L. Gizon , A. C. Birch
‹ Prev 1 2 3 10 Next ›