Related papers: Evidence for a sharp structure variation inside a …
Asteroseismology is found to be a excellent tool for detecting diffusion-induced helium gradients inside main-sequence A stars. Models have been computed for 1.6 and 2.0 M$_{\odot}$ stars with pure helium diffusion, at different ages, so…
The large number of stars for which uninterrupted high-precision photometric timeseries data are being collected with \textit{Kepler} and CoRoT initiated the development of automated methods to analyse the stochastically excited…
Seismic analyses of the CoRoT target HD 49933 have revealed a magnetic cycle. Further insight reveals that frequency shifts of oscillation modes vary as a function of frequency, following a similar pattern to that found in the Sun. In this…
Recent measurements of magnetic field strength inside the radiative interior of red giant stars open the way towards the characterization of the geometry of stable large-scale magnetic fields. However, current measurements do not properly…
A precise characterisation of the red giants in the seismology fields of the CoRoT satellite is a prerequisite for further in-depth seismic modelling. High-resolution FEROS and HARPS spectra were obtained as part of the ground-based…
A 10-night asteroseismic observation programme has been conducted in January 2004 with the spectrometer Harps at the ES0 3.6-m telescope. The selected target, the 6th magnitude F5V star HD 49933, was chosen among the prime candidates of…
We present a simple diagnostic that can be used to constrain the location of the differential rotation in red giants with measured mixed mode rotational splittings. Specifically, in red giants with radii $\sim 4R_\odot$, the splittings of…
The characteristics of the type II bursts with herringbone structure observed both by ground based radio telescopes (UTR-2, URAN-2) and spaceborn spectrometers (STEREO A-B) are discussed. The burst was recorded on 7 June, 2011 in the…
Structures of radio galaxies have the potential to reveal inconstancy in the axis of the beams, which reflect the stability in the spin axis of the supermassive black hole at the centre. We present radio observations of the giant radio…
The second data release of the Gaia mission has revealed a very rich structure in local velocity space. In terms of in-plane motions, this rich structure is also seen as multiple ridges in the actions of the axisymmetric background…
Observations of the yellow hypergiant Rho Cas obtained in 2007-2011 in a wide wavelength region with spectral resolution about 60000 have enabled studies of features of its optical spectrum in detail and brought to light previously unknown…
We study acoustic oscillations (eigenfrequencies, velocity distributions, damping times) of normal crusts of strange stars. These oscillations are very specific because of huge density jump at the interface between the normal crust and the…
The CoRoT short asteroseismic runs give us the opportunity to observe a large variety of late-type stars through their solar-like oscillations. We report the observation and modeling of the F5V star HD 175272. Our aim is to define a method…
CoRoT and Kepler observations of red giant stars revealed very rich spectra of non-radial solar-like oscillations. Of particular interest was the detection of mixed modes that exhibit significant amplitude, both in the core and at the…
Aims: We aim at characterizing the inward transition from convective to radiative energy transport at the base of the convective envelope of the solar-like oscillator HD 52265 recently observed by the CoRoT satellite. Methods: We…
HD 52265 is the only known exoplanet-host star selected as a main target for the seismology programme of the CoRoT satellite. As such, it will be observed continuously during five months, which is of particular interest in the framework of…
The aim of this work was to use a multi-approach technique to derive the most accurate values possible of the physical parameters of the \delta Sct star HD174966. In addition, we searched for a periodic pattern in the frequency spectra with…
The detection with CoRoT of solar-like oscillations in nearly 800 red giants in the first 150-days long observational run paves the way for detailed studies of populations of galactic-disk red giants. We investigate which information on the…
Space asteroseismology reveals that stellar structure and evolution models of intermediate- and high-mass stars are in need of improvement in terms of angular momentum and chemical element transport. We aim to probe the interior structure…
Context : On its asteroseismic side, the initial run of CoRoT was partly devoted to the solar like star HD49933.The eigenmodes of this F dwarf have been observed with unprecedented accuracy. Aims : We investigate quantitatively the impact…