84 citations · 1.3k across the 43 of their papers we have counts for
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A HARPS radial velocity search for planets in the Scorpius-Centaurus association. And its combination with the HARPS and SOPHIE young nearby stars (YNS) surveys
Antoine Grandjean, A. -M. Lagrange, N. Meunier +13
The Scorpius-Centaurus (Sco-Cen) young and nearby massive star-forming region is particularly well suited for extrasolar planet searches with both direct imaging and radial velocit…
The binary system of the spinning-top Be star Achernar
P. Kervella, S. Borgniet, A. Domiciano de Souza +16
Achernar, the closest and brightest classical Be star, presents rotational flattening, gravity darkening, occasional emission lines due to a gaseous disk, and an extended polar win…
Mid-infrared circumstellar emission of the long-period Cepheid l Carinae resolved with VLTI/MATISSE
V. Hocdé, N. Nardetto, A. Matter +149
The nature of circumstellar envelopes (CSE) around Cepheids is still a matter of debate. The physical origin of their infrared (IR) excess could be either a shell of ionized gas, o…
Activity time series of old stars from late F to early K. V. Effect on exoplanet detectability with high-precision astrometry
N. Meunier, A. -M. Lagrange, S. Borgniet
Stellar activity strongly affects and may prevent the detection of Earth-mass planets in the habitable zone of solar-type stars with radial velocity technics. Astrometry is in prin…
Pulsating chromosphere of classical Cepheids. Calcium infrared triplet and H profile variations
V. Hocdé, N. Nardetto, S. Borgniet +10
It has been shown recently that the infrared emission of Cepheids, which is constant over the pulsation cycle, might be due to a pulsating shell of ionized gas of about 15\% of the…
The Leavitt law of Milky Way Cepheids from Gaia DR2 static companion parallaxes
Louise Breuval, Pierre Kervella, Frédéric Arenou +13
Classical Cepheids (CCs) are at the heart of the empirical extragalactic distance ladder. Milky Way CCs are the only stars of this class accessible to trigonometric parallax measur…
A thin shell of ionized gas explaining the IR excess of classical Cepheids
V. Hocdé, N. Nardetto, E. Lagadec +12
Despite observational evidences, InfraRed (IR) excess of classical Cepheids are seldom studied and poorly understood, but probably induces systematics on the Period-Luminosity (PL)…
The detection and characterisation of 54 massive companions with the SOPHIE spectrograph -- 7 new brown dwarfs and constraints on the BD desert
F. Kiefer, G. Hébrard, J. Sahlmann +35
Brown-dwarfs are substellar objects with masses intermediate between planets and stars within about 13-80Mjup. While isolated BDs are most likely produced by gravitational collapse…
Consistent radial velocities of classical Cepheids from the cross-correlation technique
Simon Borgniet, Pierre Kervella, Nicolas Nardetto +11
Accurate radial velocities () of Cepheids are mandatory within the context of distance measurements via the Baade-Wesselink technique. The most common de…
Activity time series of old stars from late F to early K. I. Simulating radial velocity, astrometry, photometry, and chromospheric emission
N. Meunier, A. -M. Lagrange, T. Boulet +1
Solar simulations and observations show that the detection of long-period Earth-like planets is expected to be very difficult with radial velocity techniques in the solar case beca…
Multiplicity of Galactic Cepheids from long-baseline interferometry. IV. New detected companions from MIRC and PIONIER observations
A. Gallenne, P. Kervella, S. Borgniet +10
We aim at detecting and characterizing the main-sequence companions of a sample of known and suspected Galactic binary Cepheids. We used the multi-telescope interferometric combine…
A geometrical 1% distance to the short-period binary Cepheid V1334 Cygni
A. Gallenne, P. Kervella, N. R. Evans +18
Cepheid stars play a considerable role as extragalactic distances indicators, thanks to the simple empirical relation between their pulsation period and their luminosity. They over…
CRIRES high-resolution infrared spectroscopy of the long-period Cepheid l Car
N. Nardetto, E. Poretti, A. Gallenne +17
The dynamical structure of the atmosphere of Cepheids has been well studied in the optical. Several authors have found very interesting spectral features in the J band, but little…
Optical interferometry and Gaia parallaxes for a robust calibration of the Cepheid distance scale
Pierre Kervella, Antoine Mérand, Alexandre Gallenne +5
We present the modeling tool we developed to incorporate multi-technique observations of Cepheids in a single pulsation model: the Spectro-Photo-Interferometry of Pulsating Stars (…
Toward a renewed Galactic Cepheid distance scale from Gaia and optical interferometry
Pierre Kervella, Antoine Mérand, Alexandre Gallenne +9
Through an innovative combination of multiple observing techniques and mod- eling, we are assembling a comprehensive understanding of the pulsation and close environment of Cepheid…
Variability of stellar granulation and convective blueshift with spectral type and magnetic activity. I. K and G main sequence stars
N. Meunier, A. -M. Lagrange, L. Mbemba Kabuiku +3
In solar-type stars, the attenuation of convective blueshift by stellar magnetic activity dominates the RV variations over the low amplitude signal induced by low mass planets. Mod…
The SOPHIE search for northern extrasolar planets VIII. Follow-up of ELODIE candidates: long-period brown-dwarf companions
F. Bouchy, D. Ségransan, R. F. Díaz +29
Long-period brown dwarf companions detected in radial velocity surveys are important targets for direct imaging and astrometry to calibrate the mass-luminosity relation of substell…
Using the Sun to estimate Earth-like planets detection capabilities. V. Parameterizing the impact of solar activity components on radial velocities
Simon Borgniet, Nadège Meunier, Anne-Marie Lagrange
Stellar activity induced by active structures (eg, spots, faculae) is known to strongly impact the radial velocity time series. It then limits the detection of small planetary RV s…
Upgrading the Solar-Stellar Connection: News about activity in Cool Stars
H. M. Günther, K. Poppenhaeger, P. Testa +9
In this splinter session, ten speakers presented results on solar and stellar activity and how the two fields are connected. This was followed by a lively discussion and supplement…
The fundamental parameters of the roAp star 10 Aql
K. Perraut, S. Borgniet, M. Cunha +12
Due to the strong magnetic field and related abnormal surface layers existing in rapidly oscillating Ap stars, systematic errors are likely to be present when determining their eff…