Results 1 to 10 of about 494 (114)

The quiet-Sun photosphere and chromosphere [PDF]

Philosophical Transactions Series A, Mathematical, Physical, and Engineering Sciences, 2012
Abstract The overall structure and the fine structure of the solar photosphere outside active regions are largely understood, except possibly the important roles of a turbulent near-surface dynamo at its bottom, internal gravity waves at its top and small-scale vorticity. Classical one-dimensional static radiation-escape modelling has
Robert J Rütten
exaly   +4 more sources

Linear Polarization Features in the Quiet-Sun Photosphere: Structure and Dynamics. [PDF]

Sol Phys, 2018
20 pages, 9 figures, Accepted for publication in the Solar Physics ...
Kianfar S, Jafarzadeh S, Mirtorabi MT, Riethmüller TL.   +3 more
europepmc   +7 more sources

Quantifying Poynting Flux in the Quiet Sun Photosphere

The Astrophysical Journal, 2023
Abstract Poynting flux is the flux of magnetic energy, which is responsible for chromospheric and coronal heating in the solar atmosphere. It is defined as a cross product of the electric and magnetic fields, and in ideal MHD conditions it can be expressed in terms of the magnetic field and plasma velocity.
Dennis Tilipman, Maria Kazachenko, Benoit Tremblay, Ivan Milić, Valentin Martínez Pillet, Matthias Rempel   +5 more
openaire   +3 more sources

THE SUN’S PHOTOSPHERIC CONVECTION SPECTRUM [PDF]

The Astrophysical Journal, 2015
Spectra of the cellular photospheric flows are determined from full-disk Doppler velocity observations acquired by the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO) spacecraft. Three different analysis methods are used to separately determine spectral coefficients representing the poloidal flows, the toroidal
David H. Hathaway, Thibaud Teil, Aimee A. Norton, Irina Kitiashvili   +3 more
openaire   +2 more sources

Photospheric downward plasma motions in the quiet Sun [PDF]

Astronomy & Astrophysics, 2014
18 pages, 14 ...
Noda, Carlos Quintero, Cobo, Basilio Ruiz, Suárez, David Orozco   +2 more
openaire   +2 more sources

Reversed granulation in mid-photosphere of the Sun [PDF]

Proceedings of the International Astronomical Union, 2006
AbstractReversed granulation is predicted by numerical simulations and has been observed in the wings of chromospheric lines. Here we present reversed granulation in high spatial, spectral and temporal resolution, extracted from the photospheric Fe I 7090.4 Å line core intensities, once taking into account the velocity effects.
Janssen, Katja, Cauzzi, Gianna
openaire   +2 more sources

Photospheric activity of the Sun with VIRGO and GOLF [PDF]

Astronomy & Astrophysics, 2017
We study the variability of solar activity using new photospheric proxies originally developed for the analysis of stellar magnetism with the CoRoT and Kepler photometric observations. These proxies were obtained by tracking the temporal modulations in the observations associated with the spots and magnetic features as the Sun rotates.
Salabert, D., García, R. A., Jiménez, A., Bertello, L., Corsaro, E., Pallé, P. L.   +5 more
  +6 more sources

DKIST Unveils the Serpentine Topology of Quiet Sun Magnetism in the Photosphere

The Astrophysical Journal Letters, 2023
Abstract We present the first quiet Sun spectropolarimetric observations obtained with the Visible SpectroPolarimeter at the 4 m Daniel K. Inouye Solar Telescope. We recorded observations in a wavelength range that includes the magnetically sensitive Fe i 6301.5/6302.5 Å doublet.
Campbell, R.J., Keys, P.H., Mathioudakis, M., Wöger, F., Schad, T., Tritschler, A., de Wijn, A.G., Smitha, H.N., Beck, C., Christian, D.J., Jess, D.B., Erdélyi, R.   +11 more
openaire   +6 more sources

The photospheric boundary of Sun-to-Earth coupled models [PDF]

Journal of Atmospheric and Solar-Terrestrial Physics, 2004
The least understood component of the Sun-to-Earth coupled system is the solar atmosphere-the visible layers of the Sun that encompass the photosphere, chromosphere, transition region and low corona. Coronal mass ejections (CMEs), principal drivers of space weather, are magnetically driven phenomena that are thought to originate in the low solar corona.
Abbett, William P, Mikic, Z, Linker, J A, McTiernan, J M, Magara, T, Fisher, G H   +5 more
openaire   +2 more sources

Photospheric Swirls in a Quiet-Sun Region

The Astrophysical Journal
Abstract Swirl-shaped flow structures have been observed throughout the solar atmosphere, in both emission and absorption, at different altitudes and locations, and are believed to be associated with magnetic structures. However, the distribution patterns of such swirls, especially their spatial positions, remain unclear.
Xie, Q., Liu, J., Nelson, C.J., Erdélyi, R., Wang, Y.   +4 more
openaire   +4 more sources