Related papers: The fundamental parameters of the roAp star alpha …

We present K-band observations of five Mira stars with the IOTA interferometer. The interferograms were obtained with the FLUOR fiber optics beam combiner which provides high-accuracy visibility measurements in spite of time-variable…

Using \tess\ short-cadence (120\,s) SAP flux, we identified a rotational frequency of 0.09655\,$\mathrm{d}^{-1}$ ($P_\mathrm{rot}=10.35733$\,d). Wavelet analysis reveals that while the amplitudes of the harmonic components vary over time,…

At radio wavelengths, solar-type stars emit thermal free-free and gyroresonance, gyrosynchrotron, and impulsive coherent emission. Thermal free-free emission originates at layers where the optical depth is close to unit, while high…

Rapidly oscillating Ap stars are unique objects in the potential they offer to study the interplay between a number of important physical phenomena, in particular, pulsations, magnetic fields, diffusion, and convection. Nevertheless, the…

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…

The growing interest in solar twins is motivated by the possibility of comparing them directly to the Sun. To carry on this kind of analysis, we need to know their physical characteristics with precision. Our first objective is to use…

A set of long and nearly continuous observations of alpha Centauri A should allow us to derive an accurate set of asteroseismic constraints to compare to models, and make inferences on the internal structure of our closest stellar…

Observations of the southern Cepheid l Car to yield the mean angular diameter and angular pulsation amplitude have been made with the Sydney University Stellar Interferometer (SUSI) at a wavelength of 696 nm. The resulting mean…

Recently we have demonstrated that high-precision polarization observations can detect the polarization resulting from the rotational distortion of a rapidly rotating B-type star. Here we investigate the extension of this approach to an…

We present K'-band observations of five Mira stars with the IOTA interferometer. The interferograms were obtained with the FLUOR fiber optics beam combiner, which provides high-accuracy visibility measurements in spite of time-variable…

We present K-band commissioning observations of the Mira star prototype o Cet obtained at the ESO Very Large Telescope Interferometer (VLTI) with the VINCI instrument and two siderostats. The observations were carried out between 2001…

We present the results of a systematic search for new rapidly oscillating Ap (roAp) stars using the 2-min cadence data collected by the Transiting Exoplanet Survey Satellite (TESS) during its Cycle 1 observations. We identify 12 new roAp…

We present the first speckle interferometric observations of R CrB, the prototype of a class of peculiar stars which undergo irregular declines in their visible light curves. The observations were carried out with the 6m telescope at the…

We present the first observation of a solar prominence at $84-116$ GHz using the high resolution interferometric imaging of ALMA. Simultaneous observations in H$\alpha$ from Bia{\l}kaw Observatory and with SDO/AIA reveal similar prominence…

The Herbig Ae/Be star LkHalpha 101 has been imaged at high angular resolution at a number of wavelengths in the near-infrared (from 1 to 3 microns) using the Keck 1 Telescope, and also observed in the mid-infrared (11.15 microns) using the…

Three topics are discussed: 1) Photometric observations of the rapidly oscillating Ap stars have shown that the pulsation amplitude drops dramatically as a function of wavelength from the blue to the red. A theoretical derivation, plus…

We find the angular diameter of R Doradus to be 57 +/- 5 mas, exceeding that of Betelgeuse and implying that R Dor is larger in apparent size than every star except the Sun. R Dor is shown to be closely related to the Mira variables. We…

Recently, Tiwari, Chaubey, & Pandey (2007) detected the bright component of the visual binary HD151878 to exhibit rapid photometric oscillations through a Johnson B filter with a period of 6 min (2.78 mHz) and a high, modulated amplitude up…

The aim of this work is to determine fundamental parameters of three Ap stars, GO And (HD 4778), $\kappa$ Psc (HD 220825), and 84 UMa (HD 120198), using spectroscopic techniques. By analysing these stars, we complete the sample of Ap stars…

We present temperature maps of RS CVn star lambda Andromedae, reconstructed from interferometric data acquired in 2010 and 2011 by the MIRC instrument at the Center for High Angular Resolution Astronomy Array. To constrain the stellar…