Related papers: Spectral Behavior of Solar Oscillations Modulated …
Solar oscillation frequencies change with the level of magnetic activity. Localizing subsurface magnetic field concentrations in the Sun with helioseismology will help us to understand the solar dynamo. Because the magnetic fields are not…
Magnetic activity changes the gravito-acoustic modes of solar-like stars and in particular their frequencies. There is an angular-degree dependence that is believed to be caused by the non-spherical nature of the magnetic activity in the…
Small cyclic variations in the frequencies of acoustic modes are expected to be a common phenomenon in solar-like pulsators, as a result of stellar magnetic activity cycles. The frequency variations observed throughout the solar and stellar…
We have studied solar cycle changes in the large frequency separations that can be observed in Birmingham Solar Oscillations Network (BiSON) data. The large frequency separation is often one of the first outputs from asteroseismic studies…
The oscillation frequencies observed in Sun-like stars are susceptible to being shifted by magnetic activity effects. The measured shifts depend on a complex relationship involving the mode type, the field strength and spatial distribution…
Activity-related variations in the solar oscillation properties have been known for 30 years. However, the relative importance of the different contributions to the observed variations is not yet fully understood. Our goal is to estimate…
We investigate spatio-temporal evolution of high-degree acoustic mode frequencies of the Sun and the surface magnetic activity, over the course of multiple solar cycles, to improve our understanding of the connection between the solar…
The success of helioseismology is due to its capability to accurately measure the p-mode parameters of the solar eigenmode spectrum, which allow us to infer unique information about the internal structure and dynamics of the Sun. It also…
In the Sun, the properties of acoustic modes are sensitive to changes in the magnetic activity. In particular, mode frequencies are observed to increase with increasing activity level. Thanks to CoRoT and Kepler, such variations have been…
Solar oscillations frequencies show a distinct change with solar activity. The changes in frequencies can be used to study the time variation of solar structure. We discuss constraints on the changes in solar structure with time as obtained…
We derive formulae connecting the frequency variations in the spectrum of solar oscillations to the dynamical quantities that are expected to change over the solar activity cycle. This is done for both centroids and the asymmetric part of…
The presence of intense magnetic fields in and around sunspots is expected to modify the solar structure and oscillation frequencies. Applying the ring diagram technique to data from the Michelson Doppler Imager (MDI) on board the Solar and…
Magnetic features on the surfaces of cool stars cause variations of their brightness. Such variations have been extensively studied for the Sun. Recent planet-hunting space telescopes allowed measuring brightness variations in hundred…
We investigate the variation of high-degree mode frequencies as a local response to the active regions in two different phases of the solar activity cycle. We find that the correlation between frequency shifts and the surface magnetic…
The unsigned mean magnetic field characterizes the magnetic energy settled in the region near the solar surface. It is one of the determinant ingredients that govern the turbulence in the photosphere, and the magnetic heating of upper…
Using full-disk observations obtained with the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO) spacecraft, we present variations of the solar acoustic mode frequencies caused by the solar activity…
The structure of the surface layers of the Sun is changed by magnetic activity which, in turn, changes the eigenfrequencies of the acoustic modes. These frequency shifts have been observed both in low- and high-degree data, and are found to…
We examine the solar-cycle variation of the power in the low-degree helioseismic modes by looking at binned power spectra from 45 years of observations with the Birmingham Solar Oscillations Network, which provides a more robust estimate of…
Oceanic atmospheric oscillations and climate variability are tightly linked and both exhibit broad band spectral content that ranges, with roughly equal strength, from annual to centennial periodicity. The explanation for variability based…
Context. Large-scale equatorial Rossby modes have been observed on the Sun over the last two solar cycles. Aims. We investigate the impact of the time-varying zonal flows on the frequencies of Rossby modes. Methods. A first-order…