Related papers: Does the Sun shrink with increasing magnetic activ…
The unprecedented precision of broadband stellar photometry achieved with the planet-hunting missions CoRoT and \textit{Kepler} initiated a new era in examining the magnetically-driven brightness variations of hundreds of thousands of…
Solar flares are intense bursts of electromagnetic radiation, which occur due to a rapid destabilization and reconnection of the magnetic field. While pre-flare signatures and trends have been investigated from magnetic observations prior…
Sun-like stars shed angular momentum due to the presence of magnetised stellar winds. Magnetohydrodynamic models have been successful in exploring the dependence of this "wind-braking torque" on various stellar properties, however the…
This topical collection summarizes recent advances in observing and modeling irradiance variations of the Sun and Sun-like stars, emphasizing the links between surface magnetic fields and the resulting solar and stellar variability. In…
Understanding the reasons of the cyclic variation of the total solar irradiance is one of the most challenging targets of modern astrophysics. These studies prove to be essential also for a more climatologic issue, associated to the global…
Using wavelet analysis approach, the temporal variations of solar activity on time scales ranging from days to decades, are examined from the daily time series of sunspot numbers. A hierarchy of changing complex periods are careful detected…
The global oscillations of the Sun are investigated on the base of three independent sets of data: 1. Records of Total Solar Irradiance (TSI). 2. The average brightness of the photosphere in MDI (SOHO) and HMI (SDO) images. 3. Records of…
The solar rotation profile is well constrained down to about 0.25 R thanks to the study of acoustic modes. Since the radius of the inner turning point of a resonant acoustic mode is inversely proportional to the ratio of its frequency to…
The irradiance of the Sun is modulated on all time scales. Small-scale solar magnetic elements composed of quiet-Sun network and active region plages contribute to this modulation on solar cycle time scales. The evaluation of their contrast…
Aims: We investigate how well modeled solar irradiances agree with measurements from the SORCE satellite, both for total solar irradiance and broken down into spectral regions on timescales of several years. Methods: We use the SATIRE model…
The total amount of solar irradiance falling on the earth's surface is an important area of study amongst the photo-voltaic (PV) engineers and remote sensing analysts. The received solar irradiance impacts the total amount of generated…
The ever increasing level of precision achieved by present and future radial-velocity instruments is opening the way to discovering very low-mass, long-period planets (e.g. solar-system analogs). These systems will be detectable as…
Using even-order frequency splitting coefficients of global p-modes it is possible to infer the magnetic field in the solar interior as a function of radial distance and latitude. Results obtained using GONG and MDI data are discussed.…
We explore the sensitivity of the frequencies of low-degree solar p-modes to near-surface magnetic flux on different spatial scales and strengths, specifically to active regions with strong magnetic fields and ephemeral regions with weak…
We have used solar oscillation frequencies and frequency splittings obtained over solar cycles 23, 24 and the rising phase of solar cycle 25 to investigate whether the tachocline properties (jump i.e., the change in the rotation rate across…
Solar irradiance is considered one of the main natural factors affecting terrestrial climate, and its variations are included in most numerical models estimating the effects of natural versus anthropogenic factors for climate change. Solar…
Context. The Sun and solar-like stars undergo activity cycles for which the underlying mechanisms are not well understood. The oscillations of the Sun are known to vary with its activity cycle and these changes provide diagnostics on the…
In addition to the `facular' brightening of active regions, the quiet Sun also contains a small scale magnetic field with associated brightenings in continuum radiation. We measure this contribution of quiet regions to the Sun's brightness…
Efforts are underway to use high-precision timing of pulsars in order to detect low-frequency gravitational waves. A limit to this technique is the timing noise generated by dispersion in the plasma along the line of sight to the pulsar,…
The Sun and Sun-like stars lose angular momentum to their magnetised stellar winds. This braking torque is coupled to the stellar magnetic field, such that changes in the strength and/or geometry of the field modifies the efficiency of this…