Related papers: Spectroscopic detection of Altair's non-radial pul…
Altair is the fastest rotating star at less than 10 parsecs from the Sun. Its precise modelling is a landmark for our understanding of stellar evolution with fast rotation, and all observational constraints are most welcome to better…
We present an asteroseismic study of the fast rotating star HD187642 (Altair), recently discovered to be a delta Scuti pulsator. We have computed models taking into account rotation for increasing rotational velocities. We investigate the…
We present an analysis of observations of the bright star Altair (alpha Aql) obtained using the star camera on the Wide-Field Infrared Explorer (WIRE) satellite. Although Altair lies within the delta Scuti instability strip, previous…
Understanding the effects of rotation in stellar evolution is key to modelling early-type stars, half of which have equatorial velocities over 100 km/s. The nearby star Altair is an example of such fast-rotating stars, and furthermore, it…
Fast rotation is responsible for important changes in the structure and evolution of stars. Optical long baseline interferometry now permits the study of its effects on the stellar surface, mainly gravity darkening and flattening. We aim to…
The A7 star Altair is one of the hottest magnetically active stars. Its proximity to the Sun allows a detailed investigation of a corona in X-rays for a star with a shallow convection zone. We used a deep XMM-Newton observation of Altair…
Altair is an A-type star known to have an appreciably oblate shape owing to its very fast rotation (~300 km/s). Despite of numerous publications on this star, its chemical abundances have been scarcely investigated so far, presumably…
Spatially resolving the surfaces of nearby stars promises to advance our knowledge of stellar physics. Using optical long-baseline interferometry, we present here a near-infrared image of the rapidly rotating hot star Altair with <1…
We present a detailed spectroscopic study of line broadening in the A7IV-V star Altair. In a wavelength region covering 690AA we reconstruct the overall broadening profile taking into account more than 650 spectral lines. From the…
An asymmetric surface brightness distribution of the rapidly rotating A7IV-V star, Altair, has been measured by the Navy Prototype Optical Interferometer (NPOI). The observations were recorded simultaneously using a triangle of three long…
We present infrared interferometric angular size measurements for the A7IV-V star Altair which indicate a non-circular projected disk brightness distribution. Given the known rapid rotation of this star, we model the data as arising from an…
Context. This research paper contains light curve modelling, spectroscopy and detailed asteroseismic studies for four out of five in total semidetached eclipsing binaries with a delta Scuti component, that have been detected to date through…
Detecting and understanding rotation in stellar interiors is nowadays one of the unsolved problems in stellar physics. Asteroseismology has been able to provide insights on rotation for the Sun, solar-like stars, and compact objects like…
$\delta$ Scuti stars are pulsating variable stars that exhibit both radial and non-radial pulsations, making them key objects for understanding stellar evolution and internal structures. The current classification of $\delta$ Scuti stars…
The radio spectra of main-sequence stars remain largely unconstrained due to the lack of observational data to inform stellar atmosphere models. As such, the dominant emission mechanisms at long wavelengths, how they vary with spectral…
We have explored a sample of suspected A-type binaries in a systematic way, both spectroscopically and photometrically. Due to their location in the H-R diagram, indications of pulsation and/or chemical peculiarities among these suspected…
Delta Scuti ($\delta$ Sct) stars are intermediate-mass pulsators, whose intrinsic oscillations have been studied for decades. However, modelling their pulsations remains a real theoretical challenge, thereby even hampering the precise…
In this paper we investigate theoretical pulsation models for the delta Scuti star 44 Tau. The star was monitored during several multisite campaigns which confirmed the presence of radial and nonradial oscillations. Moreover, its…
We report successful fitting of a Roche model, with a surface temperature gradient following the von Zeipel gravity darkening law, to observations of Altair made with the Navy Prototype Optical Interferometer. We confirm the claim by…
For the Delta Scuti star 44 Tau 13 independent frequencies have been detected in previous studies. This star is unusual among the Delta Scuti stars because of its very low v sin i value of 2 +/- 1 km/s, indicating that it is either an…