相关论文: From Solar to Stellar Brightness Variations: The E…
The Sun and stars with low magnetic activity levels, become photometrically brighter when their activity increases. Magnetically more active stars display the opposite behaviour and get fainter when their activity increases. We reproduce…
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…
Magnetic activity of the Sun and other stars causes their brightness to vary. We investigate how typical the Sun's variability is compared to other solar-like stars, i.e. those with near-solar effective temperatures and rotation periods. By…
The rotation rates and magnetic activity of Sun-like and low-mass (< 1.4 Msun) main-sequence stars are known to decline with time, and there now exist several models for the evolution of rotation and activity. However, the role that…
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…
Observations of Sun-like stars over the last half-century have improved our understanding of how magnetic dynamos, like that responsible for the 11-year solar cycle, change with rotation, mass and age. Here we show for the first time how…
The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation…
We report the statistical properties of stars and brown dwarfs obtained from four radiation hydrodynamical simulations of star cluster formation, the metallicities of which span a range from 1/100 to 3 times the solar value. Unlike previous…
To accurately measure a star's atmospheric parameters and chemical abundances, it is crucial to have high-quality spectra. Analysing the detailed chemical abundances of groups of stars can help us better understand nucleosynthesis, galactic…
Regular spaceborne measurements have revealed that solar brightness varies on multiple timescales, variations on timescales greater than a day being attributed to surface magnetic field. Independently, ground-based and spaceborne…
Deriving metallicities for solar-like stars follows well-established methods, but for cooler stars such as M dwarfs, the determination is much more complicated due to forests of molecular lines that are present. Several methods have been…
Frequency separations used to infer global properties of stars through asteroseismology can change depending on the strength and at what epoch of the stellar cycle the p-mode frequencies are measured. In the Sun these variations have been…
The amplitude and morphology of light curves of solar-like stars change substantially with increasing rotation rate: brightness variations get amplified and become more regular, which has so far not been explained. We develop a modelling…
Around 16% of the solar-like stars in our neighbourhood show IR-excesses due to debris discs and a fraction of them are known to host planets. We aim to determine in a homogeneous way the metallicity of a sample of stars with known debris…
We utilize Kepler data to study the precision differential photometric variability of solar-type and cooler stars at different timescales, ranging from half an hour to 3 months. We define a diagnostic that characterizes the median…
Due to non-homogeneous mass distribution and non-uniform velocity rate inside the Sun, the solar outer shape is distorted in latitude. In this paper, we analyze the consequences of a temporal change in this figure on the luminosity. To do…
We analyze the effect of solar features on the variability of the solar irradiance in three different spectral ranges. Our study is based on two solar-cycles' worth of full-disk photometric images from the San Fernando Observatory, obtained…
Determining stellar ages is challenging, particularly for cooler main-sequence stars. Magnetic evolution offers an observational alternative for age estimation via the age-chromospheric activity (AC) relation. We evaluate the impact of…
Comparing solar and stellar brightness variations is hampered by the difference in spectral passbands used in observations as well as by the possible difference in the inclination of their rotation axes from the line of sight. We calculate…
An analysis of some properties of stellar models as a function of metallicity Z (and helium content Y) is presented, with special attention to those stars with metallicities higher than twice or three times solar. It is shown that the…