Related papers: Lithium abundances in exoplanet-hosts stars
Searches for helium in the exospheres of exoplanets via the metastable near-infrared triplet have yielded 17 detections and 40 non-detections. We performed a comprehensive re-analysis of published studies to investigate the influence of…
Planet accretion onto solar type stars may significantly change the stellar atmospheric abundances of 6Li and 7Li if it takes place after the star has arrived at the main sequence. Ingestion of planets at an earlier phase will not affect…
The host stars of extrasolar planets tend to be metal-rich. We have examined the data for these stars for evidence of trends in other galactic parameters, without success. However, several ESP hosts are likely to be members of the thick…
Lithium is an excellent tracer of mixing in stars as it is destroyed (by nuclear reactions) at a temperature around $\sim 2.5\times 10^6$ K. The lithium destruction zone is typically located in the radiative region of a star. If the…
Directly imaged planets are self-luminous companions of pre-main sequence and young main sequence stars. They reside in wider orbits ($\sim10\mathrm{s}-1000\mathrm{s}$~AU) and generally are more massive compared to the close-in ($\lesssim…
Exoplanetary properties depend on stellar properties: to know the planet with accuracy and precision it is necessary to know the star as accurately and precisely as possible. Our immediate aim is to characterize in a homogeneous and…
The lithium abundances for 378 G/K giants are derived with non-LTE correction considered. Among these, there are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective…
The depletion of lithium during the pre-main sequence and main sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. In the…
We determine in a homogeneous way the metallicity and individual abundances of a large sample of evolved stars, with and without known planetary companions. Our methodology is based on the analysis of high-resolution echelle spectra. The…
This work aims to investigate the behaviour of the lithium abundance in stars with and without detected planets. Our study is based on a sample of 1332 FGK main-sequence stars with measured lithium abundances, for 257 of which planets were…
We want to determine the lithium abundances of solar twin stars as a function of stellar age to provide constraints for stellar evolutions models and to investigate whether there is a connection between low Li abundance and the occurrence…
We present fundamental stellar parameters and chemical abundances for a sample of 86 evolved stars with planets and for a control sample of 137 stars without planets. The analysis was based on both high S/N and resolution echelle spectra.…
Atmospheric compositions can provide powerful diagnostics of formation and migration histories of planetary systems. We investigate constraints on atmospheric abundances of H$_2$O, Na, and K, in a sample of transiting exoplanets using…
The early Universe had a chemical composition consisting of hydrogen, helium and traces of lithium1, almost all other elements were created in stars and supernovae. The mass fraction, Z, of elements more massive than helium, is called…
Lithium is a fragile but crucial chemical element in the universe, exhibits interesting and complex behaviors. Thanks to the massive spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)…
The giant planet-metallicity correlation revealed that planetary formation depends on the stellar properties. There is growing evidence that it is also valid for smaller hot planets, but it is not clear whether elements other than iron also…
It is well known that stars orbited by giant planets have higher abundances of heavy elements when compared with average field dwarfs. A number of studies have also addressed the possibility that light element abundances are different in…
Around 16% of the solar-like stars in our neighbourhood show IR-excesses due to debris discs and a fraction of them are known to host planets. We aim to determine in a homogeneous way the metallicity of a sample of stars with known debris…
We present a statistical analysis of the ages and metallicities of triple stellar systems that are known to host exoplanets. With controversial cases disregarded, so far 27 of those systems have been identified. Our analysis, based on an…
High lithium-7 ($\mathrm{^7Li}$) abundances in giants are indicative of non-standard physical processes affecting the star. Mechanisms that could produce this signature include contamination from an external source, such as planets, or…