First Results from the CHARA Array. VII. Long-Baseline Interferometric Measurements of Vega Consistent with a Pole-On, Rapidly Rotating Star

@article{Aufdenberg2006FirstRF,
  title={First Results from the CHARA Array. VII. Long-Baseline Interferometric Measurements of Vega Consistent with a Pole-On, Rapidly Rotating Star},
  author={J. Aufdenberg and A. M{\'e}rand and V. C. Foresto and O. Absil and E. Folco and P. Kervella and S. Ridgway and D. Berger and T. Brummelaar and H. Mcalister and J. Sturmann and L. Sturmann and N. Turner},
  journal={The Astrophysical Journal},
  year={2006},
  volume={645},
  pages={664-675}
}
We have obtained high-precision interferometric measurements of Vega with the CHARA Array and FLUOR beam combiner in the K’ band at projected baselines between 103m and 273m. The measured visibility amplitudes beyond the first lobe are significantly weaker than expected for a slowly rotating star characterized by a single effective temperature and surface gravity. Our measurements, when compared to synthetic visibilities and synthetic spectrophotometry from a Roche-von Zeipel gravitydarkened… Expand

Figures and Tables from this paper

Interferometric Constraints on Gravity Darkening with Application to the Modeling of Spica A & B
Abstract In 2005 we obtained very precise interferometric measurements of the pole-on rapid rotator Vega (A0 V) with the longest baselines of the Center for High Angular Angular Resolution (CHARA)Expand
Resolving Vega and the inclination controversy with CHARA/MIRC
Optical and infrared interferometers definitively established that the photometric standard Vega (={alpha} Lyrae) is a rapidly rotating star viewed nearly pole-on. Recent independent spectroscopicExpand
COLDER AND HOTTER: INTERFEROMETRIC IMAGING OF β CASSIOPEIAE AND α LEONIS
Near-infrared interferometers have recently imaged a number of rapidly rotating A-type stars, finding levels of gravity darkening inconsistent with theoretical expectations. Here, we present newExpand
Optical interferometry of early-type stars with PAVO@CHARA – I. Fundamental stellar properties
We present interferometric observations of 7 main-sequence and 3 giant stars with spectral types from B2 to F6 using the PAVO beam combiner at the CHARA array. We have directly determined the angularExpand
A near-infrared interferometric survey of debris-disc stars - III. First statistics based on 42 stars observed with CHARA/FLUOR
Context. Dust is expected to be ubiquitous in extrasolar planetary systems owing to the dynamical activity of minor bodies. Inner dust populations are, however, still poorly known because of the highExpand
Extended Envelopes around Galactic Cepheids. III. Y Ophiuchi and α Persei from Near-Infrared Interferometry with CHARA/FLUOR
Unbiased angular diameter measurements are required for accurate distances to Cepheids using the interferometric Baade-Wesselink method (IBWM). The precision of this technique is currently limited byExpand
IMAGING AND MODELING RAPIDLY ROTATING STARS: α CEPHEI AND α OPHIUCHI
We present submilliarcsecond resolution imaging and modeling of two nearby rapid rotators α Cephei and α Ophiuchi, obtained with the CHARA array—the largest optical/IR interferometer in the world.Expand
Spectro-Interferometry Studies of Velocity-Related Phenomena at the Surface of Stars: Pulsation and Rotation
We illustrate here two applications of spectro-interferometry to the study of velocity fields at the surface of stars: pulsation and rotation. Stellar pulsation has been resolved spectroscopicallyExpand
The angular sizes of dwarf stars and subgiants (Research Note) Non-linear surface brightness relations in BVRcIc from interferometry
Context. The prediction of stellar angular diameters from broadband photometry plays an important role in different applications. In particular, long-baseline interferometry, gravitationalExpand
Interferometric studies of rapid rotators
Abstract Stellar rotation, like stellar mass and metallicity, is a fundamental property of stars. Rapid rotation distorts the stellar photosphere and affects a star's luminosity, abundances andExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 55 REFERENCES
ASYMMETRIC SURFACE BRIGHTNESS DISTRIBUTION OF ALTAIR OBSERVED WITH THE NAVY PROTOTYPE OPTICAL INTERFEROMETER
An asymmetric surface brightness distribution of the rapidly rotating A7 IV-V star Altair has been measured by the Navy Prototype Optical Interferometer (NPOI). The observations were recordedExpand
First Results from the CHARA Array. I. An Interferometric and Spectroscopic Study of the Fast Rotator α Leonis (Regulus)
We report on K-band interferometric observations of the bright, rapidly rotating star Regulus (type B7 V) made with the CHARA Array on Mount Wilson, California. Through a combination ofExpand
Resolving the effects of rotation in early type stars
We review the theory of rotating stars, first developed 80 years ago. Predictions include a specific relation between shape and angular velocity and between surface location and effective temperatureExpand
Resolving the effects of rotation in altair with long-baseline interferometry
We report the 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 OpticalExpand
On the Near-Infrared Size of Vega
Near-infrared (2.2 μm) long baseline interferometric observations of Vega are presented. The stellar disk of the star has been resolved, and the data have been fitted with a limb-darkened stellarExpand
Circumstellar material in the Vega inner system revealed by CHARA/FLUOR
Context. Only a handful of debris disks have been imaged up to now. Due to the need for high dynamic range and high angular resolution, very little is known about the inner planetary region, whereExpand
VEGA : A RAPIDLY ROTATING POLE-ON STAR
High-dispersion (2.4 A/mm), ultrahigh signal-to-noise ratio (3000:1) Reticon spectra of Vega revealed two distinct types of profiles. The strong lines exhibit classical rotational profiles withExpand
Hubble Space Telescope Absolute Spectrophotometry of Vega from the Far-Ultraviolet to the Infrared
The Space Telescope Imaging Spectrograph (STIS) has measured the absolute flux for Vega from 0.17–1.01 μm on the Hubble Space Telescope white dwarf (WD) flux scale. These data are saturated by up toExpand
A Study of the Near-Ultraviolet Spectrum of Vega
UV, optical, and near-IR spectra of Vega have been combined to test our understanding of stellar atmospheric opacities and to examine the possibility of constraining chemical abundances fromExpand
The interferometric diameter and internal structure of Sirius A
The interferometric observations of dwarf stars in the solar neighbourhood, combined with Hipparcos parallaxes provide very precise values of their linear diameters. In this paper, we report theExpand
...
1
2
3
4
5
...