Related papers: Does solar structure vary with solar magnetic acti…
A solar-type dynamo model in a spherical shell is developed with allowance for random dependence of the poloidal field generation mechanism on time and latitude. The model shows repeatable epochs of strongly decreased amplitude of magnetic…
We use helioseismic data from ground and space-based instruments to analyze how solar rotation has changed since the beginning of solar Cycle 23 with emphasis on studying the differences between Cycles 23 and 24. We find that the nature of…
The Sun experienced a period of unprecedented activity during the 20th century, now called the Modern Maximum (MM). The decay of the MM after cycle 19 has changed the Sun, the heliosphere, and the planetary environments in many ways.…
Understanding the irregular variation of the solar cycle is crucial due to its significant impact on global climates and the heliosphere. Since the polar magnetic field determines the amplitude of the next solar cycle, variations in the…
We study the connections between the sun's convection zone and the evolution of the solar wind and corona. We let the magnetic fields generated by a 2.5D axisymmetric kinematic dynamo code (STELEM) evolve in a 2.5D axisymmetric coronal…
It has been demonstrated that frequencies of f-modes can be used to estimate the solar radius to a good accuracy. These frequencies have been used to study temporal variations in the solar radius with conflicting results. The variation in…
AIM: To study the variation of the angular momentum and the rotational kinetic energy of the Sun, and associated variations in the gravitational multipole moments, on a timescale of the solar cycle. METHOD: Inverting helioseismic rotational…
We have evaluated fluctuations in neutrino fluxes caused by solar gravity (g) modes based on the analysis of linear adiabatic oscillation of a spherically symmetric star. We find that the first-order fluctuation is zero due to geometrical…
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…
The goal of this research is to investigate how magnetic field affects the dynamics of granular convection and excitation of solar oscillations by means of realistic numerical simulations. We have used a 3D, compressible, non-linear…
To better understand the influence of the activity cycle on the solar atmosphere, we report the time variation of the radius observed at 37 GHz ($\lambda$=8.1 mm) obtained by the Mets\"ahovi Radio Observatory (MRO) through Solar Cycles 22…
Solar inertial modes are believed to play important diagnostic and dynamical roles in the Sun's differentially rotating convection zone. However, the coupling of these modes to the radiative interior has not yet been discussed. We aim to…
We compare spectra of the zonal harmonics of the large-scale magnetic field of the Sun using observation results and solar dynamo models. The main solar activity cycle as recorded in these tracers is a much more complicated phenomenon than…
It is widely reported that the power spectra of magnetic field and velocity fluctuations in the solar wind have power law scalings with inertial-range spectral indices of -5/3 and -3/2 respectively. Studies of solar wind turbulence have…
Using data from the Global Oscillation Network Group (GONG) covering the period from 1995 to 1998, we study the change with solar activity in solar f-mode frequencies. The results are compared with similar changes detected from the…
In this paper, I present the results on large-scale evolution of density turbulence of solar wind in the inner heliosphere during 1985 - 2009. At a given distance from the Sun, the density turbulence is maximum around the maximum phase of…
Although helioseismology has been used as an effective tool for studying the physical mechanisms acting in most of the solar interior, the microscopic and dynamics of the deep core is still not well understood. Helioseismological anomalies…
The magnetic cycle of the Sun, as manifested in the cyclic appearance of sunspots, significantly influences our space environment and space-based technologies by generating what is now termed as space weather. Long-term variation in the…
Recent analyses of solar photospheric abundances suggest that the oxygen abundance in the solar atmosphere needs to be revised downwards. In this study we investigate the consequence of this revision on helioseismic analyses of the depth of…
(abridged) The Sun's magnetic activity has steadily declined during its main-sequence life. While the solar photospheric luminosity was about 30% lower 4.6 Gyr ago when the Sun arrived on the main sequence compared to present-day levels,…