相关论文: Light elements in stars with exoplanets
Planets and stars are expected to be compositionally linked because they accrete from the same material reservoir. However, astronomical observations revealed the existence of exoplanets whose bulk density is far higher than what is…
In this paper we present beryllium (Be) abundances in a large sample of 41 extra-solar planet host stars, and for 29 stars without any known planetary-mass companion, spanning a large range of effective temperatures. The Be abundances were…
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.…
I will discuss the presence of massive star clusters in starburst galaxies with an emphasis on low mass galaxies outside the local group. I will show that such galaxies, with respect to their mass and luminosity, may be very rich in young…
The presence of certain elements within a star, and by extension its planet, strongly impacts the formation and evolution of the planetary system. The positive correlation between a host star's iron-content and the presence of an orbiting…
We present elemental abundances of 118 stars (28 of which are known extrasolar planetary host stars) observed as part of the Anglo-Australian Planet Search. Abundances of O, Mg, Cr, Y, Zr, Ba, Nd and Eu (along with previously published…
Trends in the planet population with host star mass provide an avenue to constrain planet formation theories. We derive the planet radius distribution function for Kepler stars of different spectral types, sampling a range in host star…
The oldest stars in the universe retain to a great extent detailed information on the chemical composition of the interstellar medium at the time of their birth. Hence the earliest phases of Galactic chemical evolution and nucleosynthesis…
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…
In this paper, we present a study of the abundances of Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni in a large set of stars known to harbor giant planets, as well as in a comparison sample of stars not known to have any planet ary-mass companions.…
The past few years have seen a steady progress in the determination of element abundances at high redshifts, with new and more accurate measures of metallicities in star-forming galaxies, in QSO absorbers, and in the intergalactic medium.…
I summarize the results of 15 years of research on the surface abundances of stars in globular clusters. Globular-cluster stars afford a unique view of the physical processes that shape the surface abundances of stars on and beyond the…
We have investigated the abundance anomalies of lithium for stars with planets in the temperature range of 5600--5900 K reported by Israelian and coworkers, as compared to 20 normal stars at the same temperature and metallicity ranges. Our…
Precise abundances of 18 elements have been derived for ten stars known to host giant planets from high signal-to-noise ratio, high-resolution echelle spectroscopy. Internal uncertainties in the derived abundances are typically <=0.05 dex.…
Stellar elemental abundances direct impact planetary interior structure and mineralogy, surface composition, and life. However, the different communities that are necessary for planetary habitability exploration (astrophysics, planetary…
Nine metal-polluted white dwarfs are observed with medium-resolution optical spectroscopy,where photospheric abundances are determined and interpreted through comparison against solar system objects. An improved method of making such…
Lightning is an important electrical phenomenon, known to exist in several Solar System planets. It carries information on convection and cloud formation, and may be important for pre-biotic chemistry. Exoplanets and brown dwarfs have been…
The formation of sdBs is still puzzling, as is the chemical composition of their atmospheres. While helium and other light elements are depleted relative to solar values, heavy elements are highly enriched. Diffusion processes in the hot,…
With the goal of confirming the metallicity "excess" present in stars with planetary-mass companions, we present in this paper a high-precision spectroscopic study of a sample of dwarfs included in the CORALIE extrasolar planet survey. The…
Although indirect evidence for the presence of magnetic fields in high-mass stars is regularly reported in the literature, the detection of these fields remains an extremely challenging observational problem. We review the recent…