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Last name: BONNEAU
First name: Daniel
This paper serves as a reference on how to estimate the parameters of binary stars and how to combine multiple techniques, namely astrometry, interferometry and radial velocities.
We obtained spectro-interferometric observations in the visible of $\beta$~Lyrae and $\upsilon$~Sgr using the instrument VEGA of the CHARA interferometric array. For $\beta$~Lyrae, the dispersed fringe visibilities and differential phases were obtained in spectral regions containing the H$\alpha$ and HeI 6678 lines and the H$\beta$ and HeI 4921...
We present the new speckle camera PISCO2 made in 2010-2012, for the 76-cm refractor of C6te d'Azur Observatory. It is a focal instrument dedicated to the observation of visual binary stars using high-angular-resolution speckle-interferometry techniques to partly overcome the degradation caused by atmospheric turbulence. Fitted with an EMCCD...
The JMMC Calibrator Workgroup has long developed methods to ascertain the angular diameter of stars, and provides this expertise in the SearchCal software. SearchCal dynamically finds calibrators near science objects by querying CDS hosted catalogs according to observational parameters. Initially limited to bright objects (K magnitude ≤ 5.5),...
The diameter of a star is a major observable that serves to test the validity of stellar structure theories. It is also a difficult observable that is mostly obtained with indirect methods since the stars are so remote. Today only ~600 apparent star diameters have been measured by direct methods: optical interferometry and lunar occultations....
Massive stars deeply influence their surroundings by their luminosity and the injection of kinetic energy. So far, they have mostly been studied with spatially unresolved observations, although evidence of geometrical complexity of their wind are numerous. Interferometry can provide spatially resolved observations of massive stars and their...
In long baseline interferometry, the raw fringe contrast must be calibrated to obtain the true visibility and then those observables that can be interpreted in terms of astrophysical parameters. The selection of suitable calibration stars is crucial for obtaining the ultimate precision of interferometric instruments like the VLTI. We have...
We present relative astrometric and photometric measurements of visual binaries made in 2009-2010, with the 76-cm refractor of Côte d'Azur Observatory and a pair ofsensitive EMCCD ANDOR cameras. Ourobserving list consists of optical pairs and binaries whoseorbital motion is still uncertain. Three differenttechniques were used for obtaining...
We present relative astrometric and photometric measurements of visual binaries made in 2009–2010 with the 76-cm refractor of Côte d'Azur Observatory and a pair of sensitive EMCCD ANDOR cameras. Our observing list includes optical pairs and binaries whose orbital motion is still uncertain. Three different techniques were used for obtaining...
We present relative astrometric and photometric measurements of visual double stars made in 2013–2015, with PISCO2 installed at the 76-cm refractor of Côte d'Azur Observatory in Nice (France). Our observing list contains orbital couples as well as double stars whose motion is still uncertain. Most of the observations were done in 2015 but some...
We present relative astrometric and photometric measurements of visual double stars made in 2013-2014, with PISCO2 installed at the 76-cm refractor of Côte d'Azur Observatory in Nice (France). Our observing list contains orbital couples as well as double stars whose motion is still uncertain. Three different techniques were used for obtaining...
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We present relative astrometric and photometric measurements of visual double stars made in 2013-2014 with PISCO2 installed at the 76-cm refractor of the Côte d'Azur Observatory in Nice (France). Our observation list contains orbital couples as well as double stars whose motion is still uncertain. Three different techniques were used for...