相关论文: Variations of helioseismic parameters due to magne…

In this paper, we examine a new updated solar model taking advantage of recent reexamination of the nuclear reactions rates and of the microscopic diffusion of helium and heavy elements. Our best model fits the helioseismic data reasonably…

Recent analyses of helioseismological observations seem to suggest the presence of two new phenomena connected with the dynamics of the solar convective zone. Firstly, there are present torsional oscillations with periods of about 11 years,…

The calling card of solar magnetism is the sunspot cycle, during which sunspots regularly reverse their polarity sense every 11 years. However, a number of more complicated time-dependent behaviors have also been identified. In particular,…

In its first encounter at solar distances as close as r = 0.16AU, Parker Solar Probe (PSP) observed numerous local reversals, or inversions, in the heliospheric magnetic field (HMF), which were accompanied by large spikes in solar wind…

Aims: We aim to investigate how converging flows towards active regions affect the surface transport of magnetic flux, as well as their impact on the generation of the Sun's poloidal field. The inflows constitute a potential non-linear…

We study turbulent generation of large-scale magnetic fields using nonlinear dynamo models for solar-type stars in the range of rotational periods from 14 to 30 days. Our models take into account non-linear effects of dynamical quenching of…

A magnetic flux tube may be considered both as a separate body and as a confined field. As a field, it is affected both by differential rotation ($\Omega$-effect) and cyclonic convection ($\alpha$-effect). As a body, the tube experiences…

Numerical MHD simulations play increasingly important role for understanding mechanisms of stellar magnetism. We present simulations of convection and dynamos in density-stratified rotating spherical fluid shells. We employ a new 3D…

The frequencies of solar oscillations are known to change with solar activity. We use Principal Component Analysis to examine these changes with high precision. In addition to the well-documented changes in solar normal mode oscillations…

Theoretical models for the solar dynamo range from simple low-dimensional ``toy models'' to complex 3D-MHD simulations. Here we mainly discuss appproaches that are motivated and guided by solar (and stellar) observations. We give a brief…

We study the solar-cycle variations of solar p-mode travel time for different wave packets to probe the magnetic fields at the base of the solar convection zone. We select the wave packets which return to the same spatial point after…

The storm index SYM-H, the solar wind velocity v, and interplanetary magnetic field Bz show no signatures of low-dimensional dynamics in quiet periods, but tests for determinism in the time series indicate that SYM-H exhibits a significant…

Recent progress in realistic simulations of solar convection have given us an unprecedented opportunity to evaluate the robustness of solar interior structures and dynamics obtained by methods of local helioseismology. We present results of…

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 analyze helioseismic waves near the solar equator in the presence of magnetic fields deep within the solar radiative zone. We find that reasonable magnetic fields can significantly alter the shapes of the wave profiles for helioseismic…

We analyze magnetic field data from the first six encounters of PSP, three Helios fast streams and two Ulysses south polar passes covering heliocentric distances $0.1\lesssim R\lesssim 3$ au. We use this data set to statistically determine…

Long-term variations of solar activity, including the Grand minima, are believed to result from temporal variations of dynamo parameters. The simplest approximation of dynamo waves is applied to show that cyclic variations of the parameters…

We recently presented the first 3D numerical simulation of the solar interior for which tachocline confinement was achieved by a dynamo-generated magnetic field. In this followup study, we analyze the degree of confinement as the magnetic…

The first results of the solar dynamo model that allows for the diamagnetic effect of inhomogeneous turbulence and the nonlocal alpha-effect due to the rise of magnetic loops are discussed. The nonlocal alpha-effect is not subject to the…

Selected topics in solar dynamo theory are being highlighted. The possible relevance of the near-surface shear layer is discussed. The role of turbulent downward pumping is mentioned in connection with earlier concerns that a…