Results 21 to 30 of about 4,306,191 (296)

Particle acceleration in the presence of weak turbulence at an X-type neutral point [PDF]

, 2012
We simulate the likely noisy situation near a reconnection region by superposing many 2D linear reconnection eigenmodes. The superposition of modes on the steady state X-type magnetic field creates multiple X- and O-type neutral points close to the ...
Petkaki, P., MacKinnon, A.L., Burge, C. A., MacKinnon, A. L., Burge, C.A.   +4 more
core   +1 more source

Solar magnetic fields

Journal of Astrophysics and Astronomy, 1994
Since the structuring and variability of the Sun and other stars are governed by magnetic fields, much of present-day stellar physics centers around the measurement and understanding of the magnetic fields and their interactions. The Sun, being a prototypical star, plays a unique role in astrophysics, since its proximity allows the fundamental ...
openaire   +2 more sources

MESOGRANULATION AND THE SOLAR SURFACE MAGNETIC FIELD DISTRIBUTION [PDF]

The Astrophysical Journal, 2011
The relation of the solar surface magnetic field with mesogranular cells is studied using high spatial (~ 100 km) and temporal (~ 30 sec) resolution data obtained with the IMaX instrument aboard SUNRISE. First, mesogranular cells are identified using Lagrange tracers (corks) based on horizontal velocity fields obtained through Local Correlation ...
Yelles Chaouche, L., Moreno-Insertis, F., Martínez Pillet, V., Wiegelmann, T., Bonet, J., Knölker, M., Bellot Rubio, L., del Toro Iniesta, J., Barthol, P., Gandorfer, A., Schmidt, W., Solanki, S.   +11 more
openaire   +3 more sources

On the Origin of the Photospheric Magnetic Field

The Astrophysical Journal, 2022
This article presents results that challenge the paradigms that (1) the convection zone is the source of the radial magnetic field in the photosphere and (2) that coronal currents are neutralized from the perspective of the photosphere.
Peter W. Schuck, Mark G. Linton, Kalman J. Knizhnik, James E. Leake   +3 more
doaj   +1 more source

Solar flux emergence : a three-dimensional numerical study [PDF]

, 2008
Flux is continually emerging on the Sun, making its way from the solar interior up into the atmosphere. Emergence occurs on small-scales in the quiet Sun where magnetic fragments emerge, interact and cancel and on large-scales in active regions where ...
Murray, Michelle J.
core   +2 more sources

Effects of Partial Ionization on Magnetic Flux Emergence in the Sun

The Astrophysical Journal, 2023
We have performed 3D numerical simulations to investigate the effect of partial ionization on the process of magnetic flux emergence. In our study, we have modified the single-fluid MHD equations to include the presence of neutrals and have performed two
Georgios Chouliaras, P. Syntelis, V. Archontis   +2 more
doaj   +1 more source

Solar Magnetic Fields in Association with Flares [PDF]

Symposium - International Astronomical Union, 1971
The association of Hα flares with photospheric magnetic field patterns is reviewed on the basis of empirical evidence. The insertion of flares in the H∥ and H⊥ patterns is described. Present data on the evolution of magnetic structures in connection with flares suggest that flares result from special trends in this evolution leading to stressed and/or ‘
openaire   +1 more source

Parallel and perpendicular cascades in solar wind turbulence [PDF]

, 2005
MHD-scale fluctuations in the velocity, magnetic, and density fields of the solar wind are routinely observed. The evolution of these fluctuations, as they are transported radially outwards by the solar wind, is believed to involve both wave and ...
Matthaeus, William H., Oughton, Sean, S. Oughton, W. H. Matthaeus, Oughton, S., Matthaeus, W. H.   +5 more
core   +2 more sources

Reconstructing solar magnetic fields from historical observations [PDF]

, 2022
Context. The bright regions in the solar chromosphere and temperature minimum have a good spatial correspondence with regions of intense photospheric magnetic field. Bright regions are visible in different emission lines and parts of the continuum. Their
Tähtinen, Ismo, Virtanen, I. O. I., Mursula, Kalevi, I. O. I. Virtanen, I. I. Virtanen, Pevtsov, A. A., L. Bertello, Mursula, K., Bertello, L., I. Tähtinen, A. A. Pevtsov, Virtanen, I.I., K. Mursula, Pevtsov, Alexei A.   +13 more
core   +1 more source

Fractality of Magnetic Helicity Distribution in the Solar Corona

The Astrophysical Journal
We find a universal power-law scaling of magnetic helicity distribution in the solar corona. Magnetic helicity is a dynamical invariant for ideal magnetohydrodynamics (MHD) and characterizes complex magnetic field structure by measuring the degree of ...
Anda Xiong, Shangbin Yang, Quan Wang, Xin Liu   +3 more
doaj   +1 more source