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Aims: We aim at detecting and characterizing the main-sequence companion of the Cepheid AX Cir ($P_mathrm{orb} sim $ 18 yrs). The long-term objective is to estimate the mass of both components and the distance to the system. Methods: We used the PIONIER combiner at the VLT Interferometer to obtain the first interferometric measurements of the short-period Cepheid AX Cir and its orbiting component. Results: The companion is resolved by PIONIER at a projected separation $rho = 29.2 pm 0.2$ mas and projection angle $PA = 167.6 pm 0.3^{circ}$. We measured $H$-band flux ratios between the companion and the Cepheid of $0.90 pm 0.10$ % and $0.75 pm 0.17$ %, respectively at a pulsation phase for the Cepheid $phi = 0.24$ and 0.48. The lower contrast at $phi = 0.48$ is due to increased brightness of the Cepheid compared to the $phi = 0.24$. This gives an average apparent magnitude $mmathrm{_H (comp)} = 9.06 pm 0.24$ mag. The limb-darkened angular diameter of the Cepheid at the two pulsation phases was measured to be $theta_mathrm{LD} = 0.839 pm 0.023$ mas and $theta_mathrm{LD} = 0.742 pm 0.020$ mas, respectively at $phi = 0.24$ and 0.48. A lower limit on the total mass of the system was also derived based on our measured separation, we found $M_mathrm{T} geq 9.7 pm 0.6 M_odot$.
We report new CHARA/MIRC interferometric observations of the Cepheid archetype $delta$ Cep, which aimed at detecting the newly discovered spectroscopic companion. We reached a maximum dynamic range $Delta H $ = 6.4, 5.8, and 5.2 mag, respectively wit
Our objective is to estimate the C/O ratio in the atmosphere of beta Pictoris b and obtain an estimate of the dynamical mass of the planet, as well as to refine its orbital parameters using high-precision astrometry. We used the GRAVITY instrument wi
Dusty Wolf-Rayet stars are few but remarkable in terms of dust production rates (up to one millionth of solar mass per year). Infrared excesses associated to mass-loss are found in the sub-types WC8 and WC9. Few WC9d stars are hosting a pinwheel nebu
The Exozodi survey aims to determine the occurrence rate of bright exozodiacal discs around nearby main sequence stars using infrared interferometry. Although the Exozodi survey targets have been carefully selected to avoid the presence of binary sta
Context. The multiplicity of classical Cepheids (CCs) and RR Lyrae stars (RRLs) is still imperfectly known, particularly for RRLs. Aims. In order to complement the close-in short orbital period systems presented in Paper I, our aim is to detect the w