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Related papers: Forecasting Solar Wind Speeds

200 papers

Magnetic fluctuations in the solar wind are often observed to maintain constant magnitude of the magnetic field in a manner consistent with spherically-polarized large-amplitude Alfv\'en waves. We investigate the effect of spherical…

Solar and Stellar Astrophysics · Physics 2023-11-17 Corina Dunn , Trevor Bowen , Alfred Mallet , Samuel Badman , Stuart Bale

Solar winds originate from the Sun and can be classified as fast or slow. Fast solar winds come from coronal holes at the solar poles, while slow solar winds may originate from the equatorial region or streamers. Spicules are jet-like…

Solar and Stellar Astrophysics · Physics 2024-12-25 R. Sadeghi , E. Tavabi

Mapping of magnetic field lines is important for studies of the solar wind and the sources and propagation of energetic particles between the Sun and observers. A recently developed mapping approach is generalised to use a more advanced…

Space Physics · Physics 2020-01-08 S. Tasnim , Iver H. Cairns , B. Li , M. S. Wheatland

Stellar winds from active solar type stars can play a crucial role in removal of stellar angular momentum and erosion of planetary atmospheres. However, major wind properties except for mass loss rates cannot be directly derived from…

Solar and Stellar Astrophysics · Physics 2016-02-17 Vladimir S. Airapetian , Arcadi V. Usmanov

Switchbacks -- rapid, large deflections of the solar wind's magnetic field -- have generated significant interest as possible signatures of the key mechanisms that heat the corona and accelerate the solar wind. In this context, an important…

Solar and Stellar Astrophysics · Physics 2022-11-23 Jonathan Squire , Zade Johnston , Alfred Mallet , Romain Meyrand

The solar wind is typically categorized as fast and slow based on the measured speed ($v_\mathrm{sw}$). The separation between these two regimes is often set between 400 and 600 km/s without a rigorous definition. Observations of the solar…

Solar and Stellar Astrophysics · Physics 2025-02-19 B. L. Alterman , Y. J. Rivera , S. T. Lepri , R. M. Raines

We present a series of models for the plasma properties along open magnetic flux tubes rooted in solar coronal holes, streamers, and active regions. These models represent the first self-consistent solutions that combine: (1) chromospheric…

Astrophysics · Physics 2008-11-26 Steven R. Cranmer , Adriaan A. van Ballegooijen , Richard J. Edgar

The origin and evolution of the 1/f power law observed in the energy spectrum of solar coronal and solar wind fluctuations at scales of around an hour is not entirely understood. Several existing theories aim at explaining it, involving…

Solar and Stellar Astrophysics · Physics 2022-10-26 Norbert Magyar , Tom Van Doorsselaere

We study the formation and evolution of a turbulent spectrum of Alfv\'en waves driven by reflection off the solar wind density gradients, starting from the coronal base up to 17 solar radii, well beyond the Alfv\'enic critical point. The…

Solar and Stellar Astrophysics · Physics 2009-07-22 A. Verdini , M. Velli , E. Buchlin

Magnetic field emerges at the surface of the Sun as sunspots and active regions. This process generates a poloidal magnetic field from a rising toroidal flux tube, it is a crucial but poorly understood aspect of the solar dynamo. The…

Solar and Stellar Astrophysics · Physics 2016-07-19 Aaron C. Birch , Hannah Schunker , Douglas C. Braun , Robert Cameron , Laurent Gizon , Björn Löptien , Matthias Rempel

We investigate wave propagation and energy transport in magnetic elements, which are representatives of small scale magnetic flux concentrations in the magnetic network on the Sun. This is a continuation of earlier work by Hasan et al.…

Solar and Stellar Astrophysics · Physics 2015-05-14 G. Vigeesh , S. S. Hasan , O. Steiner

The propagation of solar energetic particles (SEPs) through the heliosphere is primarily guided by the interplanetary magnetic field (IMF) which is embedded in the solar wind plasma. Large-scale IMF structures can drive transient variations…

One of the main theories for heating of the solar corona is based on the idea that solar convection shuffles and tangles magnetic field lines to make many small-scale current sheets that, via reconnection, heat coronal loops. Tiwari et al…

Solar and Stellar Astrophysics · Physics 2025-05-08 V. Aparna , Sanjiv K. Tiwari , Ronald L. Moore , Navdeep K. Panesar , Brian Welsch , Bart De Pontieu , Aimee Norton

Parker Solar Probe (PSP) observations have revealed that most of the solar wind acceleration occurs very close to the Sun. This acceleration is partly due to the global electric potential originating from the mass disparity between…

Solar and Stellar Astrophysics · Physics 2025-05-14 Maximilien Péters de Bonhome , Viviane Pierrard , Fabio Bacchini

State-of-the-art MHD calculations reveal acceptable agreement with observational data for the height profile of the temperature $T(h)$ in the transition region of solar corona. Simultaneously, the velocity of the solar wind $U(h)$ has also…

Plasma Physics · Physics 2020-07-29 A. M. Varonov

We present multicomponent solar wind models self-consistently incorporating the contribution from dissipationless, monochromatic, finite-wavelength (non-WKB), hydromagnetic, toroidal Alfv\'en waves, which are coupled to the flow only…

Astrophysics · Physics 2009-11-13 Bo Li , Xing Li

From recent high resolution observations obtained with the Swedish 1 m Solar Telescope in La Palma, we detect swaying motions of individual filament threads in the plane of the sky. The oscillatory character of these motions are comparable…

Solar and Stellar Astrophysics · Physics 2014-11-20 Y. Lin , R. Soler , O. Engvold , J. L. Ballester , Ø. Langangen , R. Oliver , L. H. M. Rouppe van der Voort

We analyzed intermittency in the solar wind, as observed on the ecliptic plane, looking at magnetic field and velocity fluctuations between 0.3 and 1 AU, for both fast and slow wind and for compressive and directional fluctuations. Our…

Astrophysics · Physics 2015-06-24 R. Bruno , V. Carbone , L. Sorriso-Valvo , B. Bavassano

A growing body of evidence suggests that the solar wind is powered to a large extent by an Alfv\'en-wave (AW) energy flux. AWs energize the solar wind via two mechanisms: heating and work. We use high-resolution direct numerical simulations…

Solar and Stellar Astrophysics · Physics 2021-05-05 Jean C. Perez , Benjamin D. G. Chandran , Kristopher G. Klein , Mihailo M. Martinović

Here we investigate the contribution of surface Alfven wave damping to the heating of the solar wind in minima conditions. These waves are present in regions of strong inhomogeneities in density or magnetic field (e. g., the border between…

Solar and Stellar Astrophysics · Physics 2015-05-14 R. M. Evans , M. Opher , V. Jatenco-Pereira , T. I. Gombosi