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Related papers: Angular Sizes and Effective Temperatures of O-type…

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High angular resolution observations at optical wavelengths provide valuable insights in stellar astrophysics, directly measuring fundamental stellar parameters, and probing stellar atmospheres, circumstellar disks, elongation of rapidly…

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of alpha Cir. This is the first detailed interferometric study of a rapidly oscillating A (roAp) star, alpha Cir being the brightest member of…

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…

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…

Solar and Stellar Astrophysics · Physics 2020-04-01 Jeremy Bailey , Daniel V. Cotton , Ian D. Howarth , Fiona Lewis , Lucyna Kedziora-Chudczer

The angular diameters of six oxygen rich Mira-type long-period variables have been measured at various near-infrared (NIR) wavelengths using the aperture masking technique in an extensive observing program from 1997 Jan to 2004 Sep. These…

Aims: A pilot project has been carried out to measure circumstellar CO emission from three OH/IR stars close to the Galactic centre. The intention was to find out whether it would be possible to conduct a large-scale survey for mass-loss…

Astrophysics of Galaxies · Physics 2009-11-13 A. Winnberg , S. Deguchi , M. J. Reid , J. Nakashima , H. Olofsson , H. J. Habing

We present new calibrations of stellar parameters of O stars at solar metallicity taking non-LTE, wind, and line-blanketing effects into account. Gravities and absolute visual magnitudes are derived from results of recent spectroscopic…

Astrophysics · Physics 2009-05-29 F. Martins , D. Schaerer , D. J. Hillier

Context: Optical interferometry is a powerful tool for observing the intensity structure and angular diameter of stars. When combined with spectroscopy and/or spectrophotometry, interferometry provides a powerful constraint for model…

Astrophysics · Physics 2009-11-13 Hilding R. Neilson , John B. Lester

High-precision interferometric measurements of pulsating stars help to characterize their close environment. In 1974, a close companion was discovered around the pulsating star beta Cep using the speckle interferometry technique and…

We report on four Chandra grating observations of the oblique magnetic rotator theta^1 Ori C (O5.5 V) covering a wide range of viewing angles with respect to the star's 1060 G dipole magnetic field. We employ line-width and centroid…

In this paper we present and analyse determinations of effective temperatures of planet-hosting stars using infrared (IR) photometry. One of our goals is the comparison with spectroscopic temperatures to evaluate the presence of systematic…

Astrophysics · Physics 2009-11-10 I. Ribas , E. Solano , E. Masana , A. Gimenez

We measured the angular diameters of six stars using the 6-element observing mode of the Navy Precision Optical Interferometer (NPOI) for the first time since the early 2000s. Four of the diameters ranged from 1.2 mas to 1.9 mas, while the…

We measured the angular diameter of the lithium-rich K giant star HD 148293 using Georgia State University's Center for High Angular Resolution Astronomy (CHARA) Array interferometer. We used our measurement to calculate the star's…

With its unprecedented light-collecting area for night-sky observations, the Cherenkov Telescope Array (CTA) holds great potential for also optical stellar astronomy, in particular as a multi-element intensity interferometer for realizing…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Dainis Dravins , Stephan LeBohec , Hannes Jensen , Paul D. Nuñez

Rapid rotation and nonradial pulsations enable Be stars to build decretion disks, where the characteristic line emission forms. A major but unconstrained fraction of Be stars owe their rapid rotation to mass and angular-momentum transfer in…

High-precision interferometric observations of six early-type main sequence stars known to harbour cold debris discs have been obtained in the near-infrared K band with the FLUOR instrument at the CHARA Array. The measured squared…

We present moderate resolution (R $\sim$ 3575) optical spectra of 19 known or suspected members of the AB Doradus and $\beta$ Pictoris Moving Groups, obtained with the DeVeny Spectrograph on the 72-inch Perkins telescope at Lowell…

Solar and Stellar Astrophysics · Physics 2012-05-04 Kyle A. McCarthy , Russel J. White

We measured the angular diameter of the exoplanet host star iota Dra with Georgia State University's Center for High Angular Resolution Astronomy (CHARA) Array interferometer, and, using the star's parallax and photometry from the…