The radii and limb darkenings of α Centauri A and B . Interferometric measurements with VLTI/PIONIER

  title={The radii and limb darkenings of $\alpha$ Centauri A and B . Interferometric measurements with VLTI/PIONIER},
  author={Pierre Kervella and Lionel Bigot and Alexandre Gallenne and Fr'ed'eric Th'evenin},
  journal={Astronomy and Astrophysics},
The photospheric radius is one of the fundamental parameters governing the radiative equilibrium of a star. We report new observations of the nearest solar-type stars α  Centauri A (G2V) and B (K1V) with the VLTI/PIONIER optical interferometer. The combination of four configurations of the VLTI enable us to measure simultaneously the limb darkened angular diameter θ LD and the limb darkening parameters of the two solar-type stars in the near-infrared H band ( λ = 1.65 μ m). We obtain… 

Physical parameters and ±0.2% parallax of the detached eclipsing binary V923 Scorpii

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In the Trenches of the Solar–Stellar Connection. I. Ultraviolet and X-Ray Flux–Flux Correlations across the Activity Cycles of the Sun and Alpha Centauri AB

  • T. Ayres
  • Physics
    The Astrophysical Journal Supplement Series
  • 2020
This study focuses on high-energy proxies of stellar magnetic activity over long-term starspot cycles of three low-activity Sun-like stars: α Centauri A (HD 128620: G2 V), α Cen B (HD 128621: K1 V),

In the Trenches of the Solar-stellar Connection. V. High-resolution Ultraviolet and X-Ray Observations of Sun-like Stars: The Curious Case of Procyon

  • T. Ayres
  • Physics
    The Astrophysical Journal
  • 2021
A joint X-ray (0.2–2 keV) and ultraviolet (1150–3000 Å) time-domain study has been carried out on three nearby bright late-type stars, bracketing the Sun in properties. Alpha Cen A (HD 128620: G2 V)

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α Centauri A is the closest solar-type star to the Sun and offers an excellent opportunity to detect the thermal emission of a mature planet heated by its host star. The MIRI coronagraph on the James

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The following is a progress report on the long-term coronal (T ∼ 1 MK) activity of α Centauri A (HD 128620: G2 V) and B (HD 128621: K1 V). Since 2005, Chandra X-Ray Observatory has carried out