NARDETTO , N.

Determining the expansion of the universe, i.e. the Hubble constant (H0) to better than 2% is required in order to understand the nature of dark energy. However, the two most accurate methods to do it, the cosmic microwave background and the distance scale ladder are inconsistent today, which is refereed as the "tension". One of the key to...

The ease of use of Surface Brightness-Colour Relations (SBCRs) is a major advantage in the determination of stellar angular diameters. It currently plays a significant role for the distance determination of eclipsing binaries and also for the characterization of exoplanets host stars. Despite the large number of existing SBCRs, strong...

International audience

We describe the data flow in the operation of the VEGA/CHARA instrument. After a brief summary of the main characteristics and scientific objectives of the VEGA instrument, we explain the standard procedure from the scientific idea up to the execution of the observation. Then, we describe the different steps done after the observation, from the...

Context. Surface brightness-colour relations (SBCRs) are largely used for general studies in stellar astrophysics and for determining extragalactic distances. Based on a careful selection of stars and a homogeneous methodology, it has been recently shown that the SBCR for late-type stars depends on the spectral type and luminosity class.Aims....

Astronomy and Astrophysics, v. 454, p. 327-332, 2006. http://dx.doi.org/10.1051/0004-6361:20054274

Context. One challenge for measuring the Hubble constant using classical Cepheids is the calibration of the Leavitt law or period-luminosity relationship. The Baade-Wesselink method for distance determination to Cepheids relies on the ratio of the measured radial velocity and pulsation velocity, the so-called projection factor and the ability...

Astronomy and Astrophysics, v. 426, p. 687-693, 2004. http://dx.doi.org/10.1051/0004-6361:20040418

Astronomy and Astrophysics, v. 471, p. 661-669, 2007. http://dx.doi.org/10.1051/0004-6361:20066853

Astronomy and Astrophysics, v. 453, p. 309-319, 2006. http://dx.doi.org/10.1051/0004-6361:20054333

Astronomy and Astrophysics, v. 457, n. 2, p. 575-579, 2006. http://dx.doi.org/10.1051/0004-6361:20065299

Astronomy and Astrophysics, v. 428, p. 131-137, 2004. http://dx.doi.org/10.1051/0004-6361:20041419