相关论文: A Note on Solar Cycle Length during the Medieval C…
In the present paper a systematic study is carried out to validate the similarity or degree of relationship between daily terrestrial cosmic rays intensity and three characteristics of about evolution of solar corona, like a number of…
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…
Solar activity is studied using a cluster analysis of the time-fluctuations of sunspot number. In the historic period (1850-1932) the cluster exponent was approximately equal to 0.37 (strong clustering) for the high activity components of…
We summarize the fifty-year concerted effort to place the "activity" of the Sun in the context of the stars. As a working definition of solar activity in the context of stars, we adopt those globally-observable variations on time scales…
We present the initial results of an observational study into the variation of the dominant length-scale of quiet solar emission: supergranulation. This length-scale reflects the radiative energy in the plasma of the upper solar…
Recent work has revealed a 62 (+/-) 3-million-year cycle in the fossil diversity in the past 542 My, however no plausible mechanism has been found. We propose that the cycle may be caused by modulation of cosmic ray (CR) flux by the Solar…
The variation of total solar irradiance (TSI) has been measured since 1978 and that of the spectral irradiance for an even shorter amount of time. Semi-empirical models are now available that reproduce over 80% of the measured irradiance…
Several recent studies utilizing different helioseismic methods have confirmed the presence of large-scale vorticity waves known as solar Rossby waves within the Sun. Rossby waves are distinct from acoustic waves, typically with longer…
The Fourier analysis of the CME occurrence data observed by the SOHO satellite shows significant power around 1.9 yr., 1.2 yr., 265 day, 39 day and 26 day periodicities which are almost similar to the periodicities detected in the Fourier…
The heliophysics catalogues published by the Ebro Observatory during 1910--1937 have been converted into a digital format in order to provide the data for computational processing. This has allowed us to study in detail the North-South…
Aims: Although the time of the Maunder minimum (1645--1715) is widely known as a period of extremely low solar activity, claims are still debated that solar activity during that period might still have been moderate, even higher than the…
The analysis of long-term variations of several solar activity indices (AI) since in last 40 years has been performed. We studied the AI which characterize the fluxes from different areas in solar atmosphere. Our consideration of mutual…
Manifestations of activity on the YZ CMi (M4.5Ve) flare star which has a rotation period of 2.77 days and belongs to a group of activity-saturated stars, are considered from long-term photometric data together with photographic measurements…
The solar minimum 23/24 is considered to be unusual because it exhibits features that differ notably from those commonly seen in pervious minima. In this letter, we analyze the solar polar magnetic field, the potential-field solution of the…
This study aims to provide further evidence for the potential influence of the global solar magnetic field on localised chromospheric jets, the macrospicules (MS). To find a connection between the long-term variation of properties of MS and…
We compute the mean interval between successive returns of the apparent geocentric solar longitude $\lambda$ to a fixed value $L \in \{0^\circ, 45^\circ, 90^\circ, \ldots, 315^\circ\}$, averaged over a multi-millennium window; this gives…
Sunspot number (SSN) is an important - albeit nuanced - parameter that can be used as an indirect measure of solar activity. Predictions of upcoming active intervals, including the peak and timing of solar maximum can have important…
We present a comprehensive analysis of Solar Cycle 25 aimed at precisely constraining the interval of its activity maximum using multiple observational parameters: sunspot number (SSN), Wolf number, the 10.7 cm solar radio flux (F10.7), the…
The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and the Earth's upper atmosphere (commonly referred to as space weather). These changes have a direct impact on the…
Although the energetic phenomena of the Sun (flares, coronal mass injections etc.) exhibit intermittent stochastic behavior in their rate of occurrence, they are well correlated to the variations of the solar cycle. In this work we study…