Related papers: Revisiting the correlation between stellar activit…
Asteroseismology is witnessing a revolution thanks to high-precise asteroseismic space data (MOST, CoRoT, Kepler, BRITE), and their large ground-based follow-up programs. Those instruments have provided an unprecedented large amount of…
Context. Monitoring of the photometric and chromospheric HK emission data series of stars similar to the Sun in age and average activity level showed that there is an empirical correlation between the average stellar chromospheric activity…
(abridged) The clustering properties of galaxies belonging to different luminosity ranges or having different morphological types are different. These characteristics or `marks' permit to understand the galaxy catalogs that carry all this…
In a system with long-ranged correlations, the behavior of correlation functions is sensitive to the presence of a boundary. We show that surface deformations strongly modify this behavior as compared to a flat surface. The modified near…
Space-borne missions CoRoT and {\it Kepler} are providing a rich harvest of high-quality constraints on solar-like pulsators. Among the seismic parameters, mode damping rates remains poorly understood and thus barely used to infer physical…
We analyse the two-point and marked correlation functions of haloes and galaxies in three variants of the chameleon $f(R)$ gravity model using N-body simulations, and compare to a fiducial $\Lambda$CDM model based on general relativity…
We examine the relationship between the frequency of close companions (stellar and planetary companions with orbital periods < 5 years) and the metallicity of their Sun-like (~ FGK) hosts. We confirm and quantify a ~4 sigma positive…
Most studies of correlations between X-ray and optical properties of galaxy clusters have used the largest samples of data available, regardless of the morphological types of clusters included. Given the increasing evidence that morphology…
Stellar models often use relations between the temperature $T$ and optical depth $\tau$ to evaluate the structure of their optically-thin outer layers. We fit a novel analytic function to the Hopf function $q(\tau)$ of a radiation-coupled…
Magnetic fields and stellar spots can alter the equivalent widths of absorption lines in stellar spectra, varying during the activity cycle. This also influences the information that we derive through spectroscopic analysis. In this study…
Context.Interpretation of light curves of many types of binary stars requires the inclusion of the (cor)relation between surface brightness and local effective gravity. Until recently, this correlation has always been modeled by a power law…
For the Sun, a tight correlation between various activity measures and oscillation frequencies is well documented. For other stars, we have abundant data on magnetic activity and its changes but not yet on its seismic signature. A…
In this work, a mass-effective temperature-surface gravity relation (MTGR) is developed for main sequence stars in the range of 6400 K < $T_{\rm eff}$ < 20000 K with log$g$ > 3.44. The MTGR allows the simple estimation of the masses of…
Observations of the thermal X-ray emission from radio pulsars implicate that the size of hot spots is much smaller then the size of the polar cap that follows from the purely dipolar geometry of pulsar magnetic field. Most plausible…
We explore the relationship between stellar surface density and gas surface density (the star-gas or S-G correlation) in a 20,000 M$_{\odot}$ simulation from the STAR FORmation in Gaseous Environments (STARFORGE) Project. We create…
The Gaia Radial Velocity Spectrometer provides the unique opportunity of a spectroscopic analysis of millions of stars at medium-resolution in the near-infrared. This wavelength range includes the Ca II infrared triplet (IRT), which is a…
The effect of stellar activity on RV appears to be a limiting factor in detecting Earth-mass planets in the habitable zone of a star similar to the Sun in spectral type and activity level. It is crucial to estimate if this conclusion remain…
Brightness variations due to dark spots on the stellar surface encode information about stellar surface rotation and magnetic activity. In this work, we analyze the Kepler long-cadence data of 26,521 main-sequence stars of spectral types M…
The direct imaging of Earth-like planets in solar neighbors is challenging. Both transit and radial velocity (RV) methods suffer from noise due to stellar activity. By choosing a typical configuration of an X array interferometer, we used…
We present empirical relations for determining the amount by which the effective temperatures and radii -- and therefore the estimated masses -- of low-mass stars and brown dwarfs are altered due to chromospheric activity. We base our…