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Related papers: Magnetic feature tracking, what determines the spe…

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We show that systematic differences between surface Doppler and magnetic element tracking measures of solar meridional flow can be explained by the effects of surface turbulent magnetic diffusion. Feature-tracking speeds are lower than…

Solar and Stellar Astrophysics · Physics 2015-05-19 Mausumi Dikpati , Peter A. Gilman , Roger K. Ulrich

Vortex-type motions have been measured by tracking bright points in high-resolution observations of the solar photosphere. These small-scale motions are thought to be determinant in the evolution of magnetic footpoints and their interaction…

Solar and Stellar Astrophysics · Physics 2015-05-18 L. Balmaceda , S. Vargas Domínguez , J. Palacios , I. Cabello , V. Domingo

We studied the solar surface flows (differential rotation and meridional circulation) using a magnetic element feature tracking technique by which the surface velocity is obtained using magnetic field data. We used the line-of-sight…

Solar and Stellar Astrophysics · Physics 2018-09-05 Shinsuke Imada , Masashi Fujiyama

We simulate the magnetic feature tracking (MFT) speed using advective-diffusive transport models in both one and two dimensions. By depositing magnetic bipolar regions at different latitudes at the Sun's surface and following their…

Solar and Stellar Astrophysics · Physics 2012-01-24 G. Guerrero , M. Rheinhardt , A. Brandenburg , M. Dikpati

The coupling between plasma flows and magnetic fields in the solar atmosphere governs the transport of angular momentum and the redistribution of magnetic flux, yet its manifestation in the magnetically dominated upper chromosphere remains…

Solar and Stellar Astrophysics · Physics 2026-05-05 Srinjana Routh , Anshu Kumari , Rohan Bose , Vaibhav Pant , Divya Paliwal , Dipankar Banerjee , Nat Gopalswamy

The outer surface layers of the sun show a clear deceleration at low latitudes. This is generally thought to be the result of a strong dominance of vertical turbulent motions associated with strong downdrafts. This strong negative radial…

Astrophysics · Physics 2009-11-13 Axel Brandenburg

We present evidence for finite magnetic helicity density in the heliosphere and numerical models thereof, and relate it to the magnetic field properties of the dynamo in the solar convection zone. We use simulations and solar wind data to…

Solar and Stellar Astrophysics · Physics 2012-08-03 Jörn Warnecke , Axel Brandenburg , Dhrubaditya Mitra

The Sun provides an excellent natural laboratory for nonlinear phenomena. We use motions of magnetic bright points on the solar surface, at the smallest scales yet observed, to study the small scale dynamics of the photospheric plasma. The…

Astrophysics · Physics 2009-11-06 J. K. Lawrence , A. C. Cadavid , A. Ruzmaikin , T. E. Berger

A recent review shows that observations performed with different telescopes, spectral lines, and interpretation methods all agree about a vertical magnetic field gradient in solar active regions on the order of 3 G/km, when a horizontal…

Solar and Stellar Astrophysics · Physics 2020-02-12 Véronique Bommier

The high cadence plasma, electric, and magnetic field measurements by the Magnetospheric MultiScale spacecraft allow us to explore the near-Earth space plasma with an unprecedented time and spatial resolution, resolving electron-scale…

The electrostatic instabilities driven by the gradients of the density, temperature and magnetic field, are discussed in their application to solar magnetic structures. Strongly growing modes are found for some typical plasma parameters.…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Vranjes , S. Poedts

Data from spacecrafts tracking exhibit many anomalies that suggest the dependence of the speed of electromagnetic radiation with the motion of its source. This dependence is different from that predicted from emission theories that long ago…

Classical Physics · Physics 2016-07-26 Luis Bilbao

The interaction of magnetic fields and convection is investigated in the context of the coronal heating problem. We study the motions of photospheric magnetic elements using filtergrams obtained at the Swedish Vacuum Solar Telescope at La…

The number of pulsars with detected emission at X-ray and gamma-ray energies has been steadily growing, showing that beams of high-energy particles are commonly accelerated in pulsar magnetospheres, even though the location and number of…

Astrophysics · Physics 2009-11-11 Isabelle A. Grenier , Alice K. Harding

We have measured the meridional motions of the magnetic elements in the Sun's surface layers since 1996 and find systematic and substantial variations. In general the meridional flow speed is fast at cycle minima and slow at cycle maxima.…

Solar and Stellar Astrophysics · Physics 2015-06-19 David H. Hathaway , Lisa Upton

We investigate the ratio of the vertical and horizontal velocities of the photospheric plasma flows in the region of emerging magnetic fields on the Sun. We carried out a study of photospheric velocities during the first hours of the…

Solar and Stellar Astrophysics · Physics 2012-12-17 A. Khlystova

Solar activity is controlled by the magnetic field, which also causes the variability of the solar irradiance that in turn is thought to influence the climate on Earth. The magnetic field manifests itself in the form of structures of…

Solar and Stellar Astrophysics · Physics 2013-07-10 T. L. Riethmüller

At kinetic scales in the solar wind, instabilities transfer energy from particles to fluctuations in the electromagnetic fields while restoring plasma conditions towards thermodynamic equilibrium. We investigate the interplay between…

Solar and Stellar Astrophysics · Physics 2023-04-05 Simon Opie , Daniel Verscharen , Christopher H. K. Chen , Christopher J. Owen , Philip A. Isenberg

The advancement of our understanding of MHD turbulence opens ways to develop new techniques to probe magnetic fields. In MHD turbulence, the velocity gradients are expected to be perpendicular to magnetic fields and this fact was used by…

Astrophysics of Galaxies · Physics 2017-03-15 Ka Ho Yuen , A. Lazarian

Using SDO/HMI and SDO/AIA data for sunspot groups of the 24th solar cycle, we analyzed magnetic properties and He II 304 emission in leading and following sunspots separately. Simultaneous examination of umbral magnetic properties and…

Solar and Stellar Astrophysics · Physics 2015-11-24 Iu. S. Zagainova , V. G. Fainshtein , V. N. Obridko
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