S. Saesen

Investigating Cepheid ℓ Carinae's cycle-to-cycle variations via contemporaneous velocimetry and interferometry

Baade-Wesselink-type (BW) techniques enable geometric distance measurements of Cepheid variable stars in the Galaxy and the Magellanic clouds. The leading uncertainties involved concern projection factors required to translate observed radial velocities (RVs) to pulsational velocities and recently discovered modulated variability. We carried out an unprecedented observational campaign involving long-baseline interferometry (VLTI/PIONIER) and spectroscopy (Euler/Coralie) to search for modulated variability in the long-period (P

Stellar variability in open clusters - I. A new class of variable stars in NGC 3766

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Detection of solar-like oscillations in the bright red giant stars γ Piscium and θ1 Tauri from a 190-day high-precision spectroscopic multi-site campaign⋆

35.5 d) Cepheid Carinae. We determine highly precise angular diameters from squared visibilities and investigate possible differences between two consecutive maximal diameters,

Stellar variability in open clusters - II. Discovery of a new period-luminosity relation in a class of fast-rotating pulsating stars in NGC 3766

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Extensive study of HD 25558, a long-period double-lined binary with two SPB components

. We characterize the modulated variability along the line-of-sight using 360 high-precision RVs. Here we report tentative evidence for modulated angular variability and confirm cycle-to-cycle differences of

On the new late B- and early A-type periodic variable stars

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An observational asteroseismic study of the pulsating B-type stars in the open cluster NGC 884

Carinaes RV variability. Two successive maxima yield

Time-Resolved Surveys of Stellar Clusters

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A line-profile analysis of the large-amplitude beta Cephei star xi1 Canis Majoris

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Ensemble Asteroseismology of the Young Open Cluster NGC 2244

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