Related papers: Models for the long-term variations of solar activ…

The Schwabe cycle of solar activity exhibits modulations and frequency fluctuations on slow time scales of centuries and millennia. Plausible physical explanations for the cause of these long-term variations of the solar cycle are still…

Having advanced knowledge of solar activity is important because the Sun's magnetic output governs space weather and impacts technologies reliant on space. However, the irregular nature of the solar cycle makes solar activity predictions a…

The meridional circulation of the Sun is observationally found to vary with the solar cycle, becoming slower during the solar maxima. We explain this by constructing a theoretical model in which the equation of the meridional circulation…

In addition to sunspots, which represent the most easily visualized manifestation of solar magnetism, cutting-edge observations of the solar atmosphere have uncovered a plethora of magnetic flux tubes, down to the resolving power of modern…

Using different proxies of solar activity, we have studied the following features of solar cycle. (i) A linear correlation between the amplitude of cycle and its decay rate, (ii) a linear correlation between the amplitude of cycle $n$ and…

Like the solar cycle, stellar activity cycles are also irregular. Observations reveal that rapidly rotating (young) Sun-like stars exhibit a high level of activity with no Maunder-like grand minima and rarely display smooth regular activity…

Accurate prediction of the 11-year solar cycle remains a major challenge in solar physics and is important for space weather forecasting. A persistent property of the cycle is its asymmetry: the rise phase is usually much shorter than the…

A long-term variation is detected in the north-south differences of the solar activity, the phase difference of hemispheric cycles alternates by four Schwabe cycles. This variability is demonstrated by two different methods. It can be the…

The paper presents a study of a solar dynamo model operating in the bulk of the convection zone with the toroidal magnetic field flux concentrated in the subsurface rotational shear layer. We explore how this type of dynamo may depend on…

We develop and subsequently explore the solution space of a simple flux transport dynamo model that incorporates a time dependent large scale meridional circulation. Based on recent observations we prescribed an analytical form for the…

The application of the Wavelet analysis and Fourier analysis to the dataset of variations of radiation fluxes of solar-like stars and the Sun is examined. In case of the Sun the wavelet-analysis helped us to see a set of values of periods…

Observations reveal a relatively small but statistically significant North-South (NS) asymmetry in sunspot activity varying on a time scale of several solar cycles. This paper proposes a dynamo model for the phenomenon of long-term NS…

We explore the importance of meridional circulation variations in modelling the irregularities of the solar cycle by using the flux transport dynamo model. We show that a fluctuating meridional circulation can reproduce some features of the…

Aims. The Sun shows strong variability in its magnetic activity, from Grand minima to Grand maxima, but the nature of the variability is not fully understood, mostly because of the insufficient length of the directly observed solar activity…

The 11-year sunspot cycle has many irregularities, the most promi- nent amongst them being the grand minima when sunspots may not be seen for several cycles. After summarizing the relevant observational data about the irregularities, we…

The 11-yr cycle of sunspots undergo amplitude modulation over longer timescales. As a part of this long-term modulation in solar activity, the decennial rhythm occasionally breaks, with quiescent phases with very few sunspots observed over…

Although the occurrence of solar irradiance variations induced by magnetic surface features (e.g., sunspots, faculae, magnetic network) is generally accepted, the existence of intrinsic luminosity changes due to the internal magnetic fields…

The Sun has a steady 11-year cycle in magnetic activity most well-known by the rising and falling in the occurrence of dark sunspots on the solar disk in visible bandpasses. The 11-year cycle is also manifest in the variations of emission…

Some selected concepts for the solar activity cycle are briefly reviewed. Cycle modulations through a stochastic alpha effect are being identified with limited scale separation ratios. Three-dimensional turbulence simulations with helicity…

Solar activity seems quite understandable when considered on the scales comparable with a solar cycle, i.e. about 11 years, and on a short time scale of about a year. A solar cycle looks basically (anti)symmetric with respect to the solar…