Related papers: Active region contributions to the solar wind over…
Observations from the NASA Solar Dynamic Observatory Atmospheric Imaging Assembly were employed to investigate targeted physical properties of coronal active region structures across the entirety of Solar Cycle 24 (dates). This is the…
The mean value of the normalized current helicity in solar active regions is on the order of 1e-8 1/m, negative in the northern hemisphere, positive in the southern hemisphere. Observations indicate that this helicity has a subsurface…
The strength and morphology of the Sun's magnetic field evolves significantly during the solar cycle, with the overall polarity of the Sun's magnetic field reversing during the maximum of solar activity. Long-term changes are also observed…
Outflows of plasma at the edges of active regions surrounded by quiet Sun are now a common observation with the Hinode satellite. While there is observational evidence to suggest that the outflows are originating in the magnetic field…
This review provides an introduction to the generation and evolution of the Sun's magnetic field, summarising both observational evidence and theoretical models. The eleven year solar cycle, which is well known from a variety of observed…
It is well accepted that the solar cycle originates from a magnetohydrodynamics dynamo deep inside the Sun. Many dynamo models have long been proposed based on a lot of observational constraints. In this paper, using 342 NSO/Kitt Peak solar…
The origin of the slow solar wind is not well understood, unlike the fast solar wind which originates from coronal holes. In-situ elemental abundances of the slow solar wind suggest that it originates from initially closed field lines that…
Strong solar magnetic fields are the energy source of intense flares and energetic coronal mass ejections of space weather importance. The key issue is the difficulty in predicting the occurrence time and location of strong solar eruptions,…
(abridged) We investigate how the properties of the corona and solar wind in the open coronal holes depend on the properties of the magnetic fields and their footpoint motions at the surface, by perfoming 1D MHD simulations from the…
The understanding of the solar magnetic coronal structure is tightly linked to the shape of open field regions, specifically coronal holes. A dynamically evolving coronal hole coincides with the local restructuring of open to closed…
The origination and generation mechanisms of small magnetic flux ropes (SFRs), which are important structures in solar wind, are not clearly known. In present study, 1993 SFRs immersed in coronal holes, active regions, and quiet Sun solar…
Potential Field Source Surface (PFSS) models are widely used to study the solar corona and form the basis for solar wind forecasting, yet often fail to reproduce observed properties of coronal holes. We analyze 702 observed coronal holes…
Waves are thought to play a significant role in the heating of the solar atmosphere and the acceleration of the wind. Among the many types of waves observed in the Sun, the so-called p-modes with a 3 mHz frequency peak dominate the lower…
Stellar coronae are believed to be the main birthplace of various stellar magnetic activities. However, the structures and properties of stellar coronae remain poorly understood. Using the Space Weather Modelling Framework with the…
The activity-related variations in the solar acoustic frequencies have been known for 30 years. However, the importance of the different contributions is still not well established. With this in mind, we developed an empirical model to…
We present independent observations of the solar-cycle variation of flows near the solar surface and at a depth of about 60 Mm, in the latitude range $\pm45^\circ$. We show that the time-varying components of the meridional flow at these…
Sun-as-a-star coronal plasma composition, derived from full-Sun spectra, and the F10.7 radio flux (2.8 GHz) have been shown to be highly correlated (r = 0.88) during solar cycle 24. However, this correlation becomes nonlinear during…
The solar minima between solar cycles 22-23, 23-24 and 24-25 are the best observed minima on record. In situ solar wind and interplanetary magnetic field measurements by the WIND and ACE spacecraft at L1 with one-hour cadence are explored…
Recent analysis of the helioseismic observations indicate that the previously observed surface torsional oscillations extend significantly downwards into the solar convection zone. In an attempt to understand these oscillations, we study…
Spectroscopic observations at extreme and far ultraviolet wavelengths have revealed systematic upflows in the solar transition region and corona. These upflows are best seen in the network structures of the quiet Sun and coronal holes,…