相关论文: Impact of stellar companions on precise radial vel…

The detection of small mass planets with the radial-velocity technique is now confronted with the interference of stellar noise. HARPS can now reach a precision below the meter-per-second, which corresponds to the amplitudes of different…

Different stellar phenomena affect radial velocities (RVs), causing variations large enough to make it difficult to identify planet signals from the stellar variability. RV variations caused by stellar oscillations and granulation can be…

The determination of extrasolar planet masses with the radial velocity (RV) technique requires spectroscopic Doppler information from the planet's host star, which varies with stellar brightness and temperature. We analyze Doppler…

Context: In the near future, new instruments such as ESPRESSO will arrive, allowing us to reach a precision in radial-velocity measurements on the order of 10 cm/s. At this level of precision, several noise sources that until now have been…

Solar contamination, due to moonlight and atmospheric scattering of sunlight, can cause systematic errors in stellar radial velocity (RV) measurements that significantly detract from the ~10cm/s sensitivity required for the detection and…

In this work we quantify the effect of an unresolved companion star on the derived stellar parameters of the primary star if a blended spectrum is fit assuming the star is single. Fitting tools that determine stellar parameters from spectra…

We investigate the effect of stellar activity and flares on short-term radial velocity measurements in the mid-M flare star CN Leo. Radial velocity variations are calculated from 181 UVES spectra obtained during three nights. We searched…

High-resolution spectrographs with precise radial velocity (PRV) capabilities require careful considerations in instrumental design and data processing in order to reach the 10 cm/s-level precision, which is needed for detecting Earth-like…

We have been monitoring 373 very bright (V < 6 mag) G and K giants with high precision optical Doppler spectroscopy for more than a decade at Lick Observatory. Our goal was to discover planetary companions around those stars and to better…

The ever increasing level of precision achieved by present and future radial-velocity instruments is opening the way to discovering very low-mass, long-period planets (e.g. solar-system analogs). These systems will be detectable as…

One source of error in high-precision radial velocity measurements of exoplanet host stars is chromatic change in Earth's atmospheric transmission during observations. Mitigation of this error requires that the photon-weighted barycentric…

The radial velocity signature of stellar noise is small, around the meter-per-second, but already too much for the detection of Earth mass planets in habitable zones. In this paper, we address the important role played by observational…

The Doppler method of exoplanet detection has been extremely successful, but suffers from contaminating noise from stellar activity. In this work a model of a rotating star with a magnetic field based on the geometry of the K2 star Epsilon…

We present the results of radial velocity measurements of two samples of active stars. The first sample contains field G and K giants across the Red Giant Branch, whereas the second sample consists of nearby young stars (d < 150 pc) with…

Aims: Stellar activity may complicate the analysis of high-precision radial-velocity spectroscopic data when looking for exoplanets signatures. We aim at quantifying the impact of stellar spots on stars with various spectral types and…

We report on 176 close (<2") stellar companions detected with high-resolution imaging near 170 hosts of Kepler Objects of Interest. These Kepler targets were prioritized for imaging follow-up based on the presence of small planets, so most…

Telluric absorption lines impact measuring precise radial velocities (RVs) from ground-based, high-resolution spectrographs. In this paper, we simulate the dependence of this impact on stellar spectral type and extend the work of the first…

Context. Identification of planetary companions of giant stars is made difficult because of the astrophysical noise, that may produce radial velocity (RV) variations similar to those induced by a companion. On the other hand any stellar…

The interactions between stars and their orbiting planets, driven by forces such as stellar radiation and gravity, play an essential role in shaping exoplanetary atmospheres and gas-rich debris discs. One way to look into the composition of…

The number of satellites on low orbit has dramatically increased over the past years, raising concerns among the astronomical community about their impact on observations. Spectroscopic observations represent a large fraction of…