Related papers: OO Dra: an Algol-type binary formed through an ext…
In this paper, we present the results of a comprehensive study of six eclipsing binaries whose components are confirmed or suspected Am stars. By combining long-term high-resolution CAOS spectroscopy and TESS photometry we have been able to…
The stellar populations of galaxies hold vital clues to their formation histories. In this paper we present results based on modeling stacked spectra of early-type galaxies drawn from the Sloan Digital Sky Survey (SDSS) as a function of…
We combine asteroseismology, optical high-resolution spectroscopy, and kinematic analysis for 26 halo red giant branch stars in the \textit{Kepler} field in the range of $-2.5<[\mathrm{{Fe}/{H}}]<-0.6$. After applying theoretically…
Classical T Tauri stars are surrounded by a circumstellar disk from which they are accreting material. This process is essential in the formation of Sun-like stars. Although often described with simple and static models, the accretion…
Multiband CCD photometric observations of SZ Her were obtained between 2008 February and May. The light curve was completely covered and indicated a significant temperature difference between both components. The light-curve synthesis…
We present the most precise to date orbital and physical parameters of the well known short period (P=5.975 d), eccentric (e=0.3) double-lined spectroscopic binary BY Draconis, a prototype of a class of late-type, active, spotted flare…
Existence of pulsating stars in eclipsing binaries has been known for decades. These types of objects are extremely valuable systems for astronomical studies as they exhibit both eclipsing and pulsation variations. The eclipsing binaries…
We used high-quality Kepler photometry and spectroscopic data to investigate the Kepler binary candidate KIC 5988140. Using the spectrum synthesis method, we derived the fundamental parameters Teff, log g, [M/H], and v.sini and the…
For a new parameterization of the modified effective chiral model, developed primarily to regulate the density content of the symmetry energy and its higher order terms, equations of state (EoSs) for hyperon-rich matter ($H$) and delta…
We present a new comprehensive study of HD81809, a nearby binary system of two solar-like stars showing high-amplitude X-ray emission and a well-defined 8-year solar-like magnetic cycle. By analyzing high-resolution spectroscopy, alongside…
The {\emph{Kepler}} space telescope has provided exquisite data to perform asteroseismic analysis on evolved star ensembles. Studying star clusters offers significant insight into stellar evolution and structure, due to having a large…
A field star, HD 61199 (V ~ 8), simultaneously observed with Procyon by the MOST (Microvariability & Oscillations of STars) satellite in continuous runs of 34, 17, and 34 days in 2004, 2005, and 2007, was found to pulsate in 11 frequencies…
In order to interpret the results of complex realistic star cluster simulations, which rely on many simplifying approximations and assumptions, it is essential to study the behavior of even more idealized models, which can highlight the…
Asteroseismology of solar-type stars has entered a new era of large surveys with the success of the NASA \textit{Kepler} mission, which is providing exquisite data on oscillations of stars across the Hertzprung-Russell (HR) diagram. From…
We report high-resolution, high-signal-to-noise, observations of the extremely metal-poor double-lined spectroscopic binary CS 22876-032. The system has a long period : P = 424.7 $\pm$ 0.6 days. It comprises two main sequence stars having…
Despite the fact that the initial helium abundance is an essential ingredient in modelling solar-type stars, its abundance in these stars remains a poorly constrained observational property. This is because the effective temperature in…
Photometric data from the Transiting Exoplanet Survey Satellite (TESS) mission and radial velocities from the Gaia mission and ground-based observations were used to model the light curves and calculate the physical parameters of the…
We present a $\approx 11.5$ year adaptive optics (AO) study of stellar variability and search for eclipsing binaries in the central $\sim 0.4$ pc ($\sim 10''$) of the Milky Way nuclear star cluster. We measure the photometry of 563 stars…
The interplay between radiative diffusion, rotation, convection, and magnetism in metallic-line chemically peculiar stars is still not fully understood. Recently, evidence has emerged that these effects can work together. Our goal is to…
In the last years, space missions such as COROT, Kepler or MOST have provided very accurate photometric observational data. In the particular case of $\delta$ Scuti stars, the observed frequency spectra have hundreds (if not thousands) of…