Related papers: A Metal-biased Planet Search
Context. Low mass stars are currently the best targets for searches for rocky planets in the habitable zone of their host star. Over the last 13 years, precise radial velocities measured with the HARPS spectrograph have identified over a…
CONTEXT. Exoplanet searches have demonstrated that giant planets are preferentially found around metal-rich stars and that their fraction increases with the stellar mass. AIMS. During the past six years, we have conducted a radial velocity…
A metal-rich environment facilitates planet formation, making metal-rich stars the most favorable targets for surveys seeking to detect new exoplanets. Using this advantage to identify likely low-mass planet hosts, however, has been…
(Abridged) Searching for planets around stars with different masses probes the outcome of planetary formation for different initial conditions. This drives observations of a sample of 102 southern nearby M dwarfs, using a fraction of our…
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…
Probing the connection between a star's metallicity and the presence and properties of any associated planets offers an observational link between conditions during the epoch of planet formation and mature planetary systems. We explore this…
Context: How planet properties depend on stellar mass is a key diagnostic of planetary formation mechanisms. Aims: This motivates planet searches around stars which are significantly more massive or less massive than the Sun, and in…
To understand the formation and evolution of solar-type stars and planets in the solar neighborhood, we need to obtain their stellar parameters with high precision. We present a catalog of precise stellar parameters for low-activity FGK…
We report on the detection of three Saturn-mass planets discovered with the HARPS instrument. HD 93083 shows radial-velocity (RV) variations best explained by the presence of a companion of 0.37 M_Jup orbiting in 143.6 days. HD 101930 b has…
We present empirical calibrations that estimate stellar metallicity, effective temperature and surface gravity as a function of Lick/IDS indices. These calibrations have been derived from a training set of 261 stars for which (1)…
We investigate a possible correlation between the orbital periods $P$ of the extra-solar planet sample and the metallicity [Fe/H] of their parent stars. Close-in planets, on a few-days orbits, are more likely to be found around metal-rich…
This work presents the medium-resolution ($R \sim 1,500$) spectroscopic follow-up of 522 low-metallicity star candidates from the Southern Photometric Local Universe Survey (S-PLUS). The objects were selected from narrow-band photometry,…
In this paper, we present our HARPS radial-velocity data for eight low-activity solar-type stars belonging to the HARPS volume-limited sample: HD6718, HD8535, HD28254, HD290327, HD43197, HD44219, HD148156, and HD156411. Keplerian fits to…
We used a sample of super-Earth-like planets detected by the Doppler spectroscopy and transit techniques to explore the dependence of orbital parameters of the planets on the metallicity of their host stars. We confirm the previous results…
We report on the first extra-solar planet discovered with the brand new HARPS instrument. The planet is a typical 'hot Jupiter' with m2sini = 0.62 MJup and an orbital period of 3.39 days, but from the photometric follow-up of its parent…
Context. Low-mass extrasolar planets are presently being discovered at an increased pace by radial velocity and transit surveys, opening a new window on planetary systems. Aims. We are conducting a high-precision radial velocity survey with…
We present stellar parameters and metallicities for 29 planet-host stars, as well as for a large volume-limited sample of 53 stars not known to be orbited by any planetary-mass companion. These stars add to the results presented in our…
I review the status of the search for extremely metal-poor halo stars with the Hamburg/ESO objective-prism survey (HES). 2194 candidate metal-poor turn-off stars and 6133 giants in the magnitude range 14 < B < 17.5 have been selected from…
Context. The presence of a small-mass planet (M$_p<$0.1\,M$_{Jup}$) seems, to date, not to depend on metallicity, however, theoretical simulations have shown that stars with subsolar metallicities may be favoured for harbouring smaller…
An abundance analysis is presented of 60 metal-poor stars drawn from catalogues of nearby stars provided by Ariyanto et al. (2005) and Schuster et al. (2006). In an attempt to isolate a sample of metal-weak thick disc stars, we applied the…