相关论文: Are Stars with Planets Polluted?

The first stars are assumed to be predominantly massive. Although, due to the low initial abundances of heavy elements the line-driven stellar winds are supposed to be inefficient in the first stars, these stars may loose a significant…

Stellar metallicity strongly correlates with the presence of planets and their properties. To check for new correlations between stars and the existence of an orbiting planet, we determine precise stellar parameters for a sample of…

The stellar metallicity is a direct measure of the amount of metals present in a galaxy, as a large part of the metals lie in its stars. In this paper we investigate new stellar metallicity indicators suitable for high-z galaxies studying…

In this article we present a detailed spectroscopic analysis of more than 50 extra-solar planet host stars. Stellar atmospheric parameters and metallicities are derived using high resolution and high S/N spectra. The spectroscopy results,…

We have studied the spectral evolution of stellar populations in function of their heavy element content and star formation, using Geneva and Padova stellar track sets, both covering a number of metallicities, and Kurucz grid of stellar…

Stellar parameters of 25 planet-hosting stars and abundances of Li, C, O, Na, Mg, Al, S, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni, Zn, Y, Zr, Ba, Ce, Pr, Nd, Sm and Eu, were studied based on homogeneous high resolution spectra and uniform…

The occurrence rate of hot Jupiters from the Kepler transit survey is roughly half that of radial velocity surveys targeting solar neighborhood stars. One hypothesis to explain this difference is that the two surveys target stars with…

The study of stellar parameters of planet-hosting stars, such as metallicity and chemical abundances, help us to understand the theory of planet formation and stellar evolution. Here, we present a catalogue of accurate stellar atmospheric…

Giant protoplanets formed by gravitational instability in the outer regions of circumstellar disks go through an early phase of quasi-static contraction during which radii are large and internal temperatures are low. The main source of…

Discovery of only handful of exoplanets required to establish a correlation between giant planet occurrence and metallicity of their host stars. More than 20 years have already passed from that discovery, however, many questions are still…

We investigated a volume-limited sample of LAMOST main-sequence stars with masses from 0.25 to 1 $M_{\odot}$ and distances of 150-350 pc to explore how the stellar initial mass function (IMF) varies with metallicity. We corrected the…

Over a quarter of white dwarfs have photospheric metal pollution, which is evidence for recent accretion of exoplanetary material. While a wide range of mechanisms have been proposed to account for this pollution, there are currently few…

We present Na, Mg and Al abundances in a set of 98 stars with known giant planets, and in a comparison sample of 41 ``single'' stars. The results show that the [X/H] abundances (with X = Na, Mg and Al) are, on average, higher in stars with…

Dust in protoplanetary disks is recognized as the building blocks of planets. In the core accretion scenario, the abundance of dust in disks (or metallicity) is crucial for forming cores of gas giants. We present our recent progress on the…

We derive stellar metallicities, light-weighted ages and stellar masses for a magnitude-limited sample of 175,128 galaxies drawn from the Sloan Digital Sky Survey Data Release Two (SDSS DR2). We compute median-likelihood estimates of these…

Planets like the Earth cannot form unless elements heavier than helium are available. These heavy elements, or `metals', were not produced in the big bang. They result from fusion inside stars and have been gradually building up over the…

The bulk-metallicity determination of giant exoplanets is essential to constrain their formation and evolution pathways and to compare them to the solar system. Previous studies inferred an inverse relation between the mass and bulk…

We have derived abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Fe, Ni and Ba for 43 metal-poor field stars in the solar neighbourhood with iron abundances [Fe/H] ranging from -0.4 to -3.0. Total abundance errors are estimated to about…

In some recent works, the C/O abundance ratio in high-metallicity stars with planets is found to vary from 0.4 to about 1.0. This has led to discussions about the existence of terrestrial planets with a carbon-dominated composition that is…

We present results from deep Spitzer/Infrared Array Camera (IRAC) observations of 28 metal-poor, strongly star-forming galaxies selected from the DEEP2 Galaxy Survey. By modelling infrared and optical photometry, we derive stellar masses…