相关论文: Stellar Parameters and Evolutionary Pathways of th…

Main-sequence stars with convective envelopes often appear larger and cooler than predicted by standard models of stellar evolution for their measured masses. This is believed to be caused by stellar activity. In a recent study, accurate…

We propose a novel method for determining the ages of low-mass, pre-main sequence stellar systems using the apsidal motion of low-mass detached eclipsing binaries. The apsidal motion of a binary system with an eccentric orbit provides…

The precise determination of the physical and dynamical parameters of the HIP 109951 triple star system (WDS J22161-0705AB) which is formed by the A, Ba, and Bb components are presented. The binary nature of component B was recently…

Stellar ages are extremely difficult to determine and often subject to large uncertainties, especially for field low-mass stars. We plan to carry out a calibration of the decrease in high-energy emissions of low-mass GKM stars with time,…

There is a well-known stellar parameter discrepancy for late K and M dwarfs, in that the observed radii and temperatures are often respectively larger and cooler than predicted by theory by several percent. In an on-going effort to…

We have found a system listed in the Kepler Binary Catalog (3.273 day period; Prsa et al. 2010) that we have determined is comprised of a low-mass, thermally-bloated, hot white dwarf orbiting an A star of about 2.3 solar masses. In this…

Tight binaries discovered in young, nearby associations, with known distances, are ideal targets to provide dynamical mass measurements to test the physics of evolutionary models at young ages and very low masses. We report for the first…

By definition, brown dwarfs never reach the main-sequence, cooling and dimming over their entire lifetime, thus making substellar models challenging to test because of the strong dependence on age. Currently, most brown dwarfs with…

We evaluated the bias and variability on the fitted age and convective core overshooting parameter for evolved binary stars accounting for observational and internal uncertainties. We considered a binary system composed of a 2.50 $M_{\sun}$…

We report spectroscopic and interferometric observations of the moderately metal-poor double-lined binary system HD 195987, with an orbital period of 57.3 days. By combining our radial-velocity and visibility measurements we determine the…

Binary star systems are important for understanding stellar structure and evolution, and are especially useful when oscillations can be detected and analysed with asteroseismology. However, only four systems are known in which solar-like…

We are carrying out an international, multi-wavelength program to determine the fundamental properties and independent distance estimates of selected eclipsing binaries in the LMC and SMC. Eclipsing binaries with well-defined double-line…

We present the results of a long term orbit monitoring program, using sparse aperture masking observations taken with NIRC2 on the Keck-II telescope, of seven G to M-type members of the Upper Scorpius subgroup of the Sco-Cen OB association.…

We explore the probable chemical signature of planet formation in the remarkable binary system HD 106515. The A star hosts a massive long-period planet with 9 MJup detected by radial velocity. We also refine stellar and planetary parameters…

We analyze an asteroseismic binary system: KIC 7107778, a non-eclipsing, unresolved target, with solar-like oscillations in both components. We used \emph{Kepler} short cadence time series spanning nearly two years to obtain the power…

Context. Typical uncertainties of ages determined for single star giants from isochrone fitting using single-epoch spectroscopy and photometry without any additional constraints are 30-50 %. Binary systems, particularly double-lined…

With the observations of an unprecedented number of oscillating subgiant stars expected from NASA's TESS mission, the asteroseismic characterization of subgiant stars will be a vital task for stellar population studies and for testing our…

Deriving precise stellar ages is a challenging task. Consequently, age-dependent relations - such as the age-metallicity and age-velocity dispersion relations of the Milky Way, or the age-rotation-activity relation of low-mass stars - are…

Double-lined eclipsing binaries allow accurate and direct determination of fundamental parameters such as mass and radius for each component, and they provide important constraints on the stellar structure and evolution models. In this…

We report the discovery and characterisation of a new M-dwarf binary, with component masses and radii of M1 = 0.244 -0.003/+0.003 Msun, R1 = 0.261 -0.009/+0.006 Rsun, M2 = 0.179 -0.001/+0.002 Msun, R2 = 0.218 -0.011/+0.007 Rsun, and orbital…