Seismic constraints on rotation of Sun-like star and mass of exoplanet.

Constraints on stellar rotation and planet mass. The dark-red and light-red regions are the 1-σ and 2- σ seismic constraints on stellar rotation in the plane (Ω / ΩSun) - (sin i), where Ω is the bulk angular velocity, ΩSun / 2 π= 0.424 μHz is the solar Ca
Constraints on stellar rotation and planet mass. The dark-red and light-red regions are the 1-σ and 2- σ seismic constraints on stellar rotation in the plane (Ω / ΩSun) - (sin i), where Ω is the bulk angular velocity, ΩSun / 2 π= 0.424 μHz is the solar Ca
Advertised on
References
Proceedings of the National Academy of Sciences, vol. 110, issue 33, pp. 13267-13271

Rotation is thought to drive cyclic magnetic activity in the Sun and Sun-like stars. Stellar dynamos, however, are poorly understood owing to the scarcity of observations of rotation and magnetic fields in stars. Here, inferences are drawn on the internal rotation of a distant Sun-like star by studying its global modes of oscillation. We report asteroseismic constraints imposed on the rotation rate and the inclination of the spin axis of the Sun-like star HD52265, a CoRoT prime target known to host a planetary companion. These seismic inferences are remarkably consistent with an independent spectroscopic observation (rotational line broadening) and with the observed rotation period of starspots. Further, asteroseismology constrains the mass of exoplanet HD52265b. Under the standard assumption that the stellar spin axis and the axis of the planetary orbit coincide, the minimum spectroscopic mass of the planet can be converted into a true mass of 1.85 +0.52- 0.42MJupiter which implies that it is a planet, not a brown dwarf.

News type
Research news

It may interest you

  • Planetary Nebula M57
    Research news
    Hydrogenated amorphous carbon grains as a carrier of unidentified IR bands in planetary nebulae
    It is well known that fullerenes – big, complex, and highly resistant carbon molecules with potential applications in nanotechnology – are mostly seen in planetary nebulae (PNe); old dying stars with progenitor masses similar to our Sun. Fullerenes, like C60 and C70, have been detected in PNe whose infrared (IR) spectra are dominated by broad unidentified IR (UIR) plateau emissions. The identification of the chemical species (structure and composition) responsible for such UIR emission widely present in the Universe is a mystery in astrochemistry; although they are believed to be carbon-rich
    Advertised on
  • Research news
    Scientific results with the QUIJOTE-MFI wide survey: The anomalous microwave emission in our Galaxy and M31
    In the 90s, the COBE satellite discovered that not all the microwave emission from our Galaxy behaved as expected. Part of this signal was later assigned to a fresh new emission component, spatially correlated with the Galactic dust emission, which showed greater importance in the microwave range of frequencies. It has been named since as “anomalous microwave emission”, or AME. The current main hypothesis to explain the AME origin is that it is emitted by small dust particles which undergo fast spinning movements. In Fernández-Torreiro et al. (2023), we study the observational properties of
    Advertised on
  • Asteroid reflectance spectra from Gaia DR3
    Research news
    Asteroid reflectance spectra from Gaia DR3: Near-UV in primitive asteroids
    Asteroids are the remnants of the planetary formation in the Solar System and so, their study helps us to understand the conditions during the early stages of the formation of our planetary system. Among asteroids, those classified as primitives present similar spectra to that of carbonaceous chondrites, i.e., they are rich in carbon and organic compounds and silicates altered by the presence of liquid water (phyllosilicates). Primitive asteroids are well characterized in various wavelength regions, showing their most diagnostic feature at 3μm. However, there is a lack of information in the
    Advertised on