Helio and Astero-Seismology and Exoplanets Search

    General
    Description

    The principal objectives of this project are: 1) to study the structure and dynamics of the solar interior, 2) to extend this study to other stars (either single or in binary systems), 3) to search for extrasolar planets using photometric methods (primarily by transits of their host stars) and their characterization with complementary radial velocity information.

    To reach our first objective, we use Helioseismology (analysis of the solar oscillation eigenmodes), a technique that enables us to infer the Sun's internal structure and dynamics with high accuracy. This project covers the various aspects necessary to attain the aforementioned objectives: instrumental and observational (with the international networks BiSON and GONG operating at the ”SolarLab” at Observatorio del Teide), reduction, analysis, and interpretation of data (in particular, the GOLF and VIRGO instruments aboard   ESA/SoHO satellite). Finally, theoretical developments in inversion techniques are carried out.

    Furthermore, Asteroseismology applies similar techniques to other oscillating stars to infer their evolutionary state as well as their internal structure and dynamics. Thanks to the high-quality photometric data collected by the CoRoT, Kepler, and TESS space missions, it is possible to extract global seismic parameters for hundreds of thousands of solar-like stars, from the main sequence through the red-giant phase. Stellar evolution models are used to find the model that best fits the observables (spectroscopic and individual mode frequencies), providing precise mass, radius, and age for the star. Binary stars provide additional strong constraints on these models and therefore allow testing the intricacies of internal stellar physics.

    Precise exoplanet characterization is critically dependent on an accurate knowledge of the host star. In particular, a reliable determination of the stellar age is required to constrain the age and evolutionary state of the planetary system, and to place robust limits on long-term habitability. At the interface between asteroseismology and exoplanet science, detailed seismic modeling of host stars is used to refine the ages of planetary systems. Strong involvement is ensured in the preparation of the ESA PLATO mission (launch expected at the end of 2026), including light-curve calibration, contributions to the science calibration and validation input catalog (scvPIC), proposals for complementary science, and ground-based follow-up observations.

    For this project, ground-based observations with the observational facilities available to IAC researchers, in particular at OCAN (Observatorios de Canarias), are key. In particular, ongoing observations with the ground-based, high-precision spectrographs on the SONG (Stellar Observations Network Group) and the Las Cumbres Observatory Network (LCO) are being conducted to improve the spectroscopic and seismic characterization of oscillating stars and to identify binary systems.

    Principal investigator

    Milestones

    1. Beck et al. (2024, A&A, 682, A7) increased the number of known solar-like oscillators in binary systems by about an order of magnitude. Such large sample allowed us to study the effects co-evolution of stellar evolution on the evolution of the binary orbits. Featured as "ESA Gaia image of the Week".
    2. Following the participation to the roadmaps in astrophysics for the ESA’s Human and Robotic Exploration Directorate in 2021, a paper in npj Microgravity was published where the key quetions in stellar physics were exposed along with proposed experiments for the future as part of that program (Mathur & Santos 2024).
    3. Merc et al. (2024, A&A, 683, A84) presented the first analysis of accretion-induced flickering variability in symbiotic binary stars from TESS lightcurves. This study significantly enlarged the known sample with such variability. This suggests that accretion disks are common in symbiotic stars.
    4. Solar magnetic activity in cycles 23&24 were analyzed by tracking GOLF low-degree p-mode frequency shifts across 3 bands, probing depths of 74–1575 km. Results suggest magnetic variations mainly occur near the surface. In cycle 24, shifts appeared earlier at high latitudes and coincided with surface activity near the equator, with stronger shifts at shallower depths.

    Related publications

    Precise mass determination for the keystone sub-Neptune planet transiting the mid-type M dwarf G 9-40 2022A&A...666A.154L
    Confirmation and characterisation of three giant planets detected by TESS from the FIES/NOT and Tull/McDonald spectrographs 2022A&A...667A..22K
    99 oscillating red-giant stars in binary systems with NASA TESS and NASA Kepler identified from the SB9-Catalogue 2022A&A...667A..31B
    A 4 Gyr M-dwarf Gyrochrone from CFHT/MegaPrime Monitoring of the Open Cluster M67 2022ApJ...938..118D
    SPECULOOS Northern Observatory: Searching for Red Worlds in the Northern Skies 2022PASP..134j5001B
    Solar-like oscillations and ellipsoidal variations in TESS observations of the binary 12 Boötis 2022MNRAS.516.3709B
    Sub-stellar companions of intermediate-mass stars with CoRoT: CoRoT-34b, CoRoT-35b, and CoRoT-36b 2022MNRAS.516..636S
    The Origin of Weakened Magnetic Braking in Old Solar Analogs 2022ApJ...933L..17M
    Magnetic activities on two single-lined RS Canum Venaticorum binaries IM Pegasi and σ Geminorum 2022MNRAS.514.4190C
    A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system 2022NatAs...6..736S
    The young HD 73583 (TOI-560) planetary system: two 10-M<SUB>⊕</SUB> mini-Neptunes transiting a 500-Myr-old, bright, and active K dwarf 2022MNRAS.514.1606B
    TOI-2046b, TOI-1181b, and TOI-1516b, three new hot Jupiters from TESS: planets orbiting a young star, a subgiant, and a normal star 2022MNRAS.513.5955K
    The TESS-Keck Survey. XI. Mass Measurements for Four Transiting Sub-Neptunes Orbiting K Dwarf TOI-1246 2022AJ....163..293T
    TOI-1670 b and c: An Inner Sub-Neptune with an Outer Warm Jupiter Unlikely to Have Originated from High-eccentricity Migration 2022AJ....163..225T
    A Radial Velocity Study of the Planetary System of π Mensae: Improved Planet Parameters for π Mensae c and a Third Planet on a 125 Day Orbit 2022AJ....163..223H
    TESS asteroseismology of the Kepler red giants 2022MNRAS.512.1677S
    The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar, and APOGEE-2 Data 2022ApJS..259...35A
    The K2 Galactic Archaeology Program Data Release 3: Age-abundance Patterns in C1-C8 and C10-C18 2022ApJ...926..191Z
    Parameters of the eclipsing binary α Draconis observed by TESS and SONG 2022MNRAS.511.2648H
    TESS Giants Transiting Giants. II. The Hottest Jupiters Orbiting Evolved Stars 2022AJ....163..120G
    Study of chemically peculiar stars - I. High-resolution spectroscopy and K2 photometry of Am stars in the region of M44 2022MNRAS.510.5854J
    No swan song for Sun-as-a-star helioseismology: Performances of the Solar-SONG prototype for individual mode characterisation 2022A&A...658A..27B
    K2-99 revisited: a non-inflated warm Jupiter, and a temperate giant planet on a 522-d orbit around a subgiant 2022MNRAS.510.5035S
    A 20 Second Cadence View of Solar-type Stars and Their Planets with TESS: Asteroseismology of Solar Analogs and a Recharacterization of π Men c 2022AJ....163...79H
    Detections of solar-like oscillations in dwarfs and subgiants with Kepler DR25 short-cadence data 2022A&A...657A..31M
    Orbital period refinement of CoRoT planets with TESS observations 2021FrASS...8..210K
    GJ 367b: A dense, ultrashort-period sub-Earth planet transiting a nearby red dwarf star 2021Sci...374.1271L
    TOI-1431b/MASCARA-5b: A Highly Irradiated Ultrahot Jupiter Orbiting One of the Hottest and Brightest Known Exoplanet Host Stars 2021AJ....162..292A
    TESS Asteroseismology of α Mensae: Benchmark Ages for a G7 Dwarf and Its M Dwarf Companion 2021ApJ...922..229C
    Magnetic and Rotational Evolution of ρ CrB from Asteroseismology with TESS 2021ApJ...921..122M
    Asteroseismology of iota Draconis and Discovery of an Additional Long-period Companion 2021AJ....162..211H
    On the relation between active-region lifetimes and the autocorrelation function of light curves 2021MNRAS.508..267S
    37 new validated planets in overlapping K2 campaigns 2021MNRAS.508..195D
    Masses and compositions of three small planets orbiting the nearby M dwarf L231-32 (TOI-270) and the M dwarf radius valley 2021MNRAS.507.2154V
    Brightness Fluctuation Spectra of Sun-like Stars. I. The Mid-frequency Continuum 2021ApJ...916...66B
    A calibration of the Rossby number from asteroseismology 2021A&A...652L...2C
    Surface Rotation and Photometric Activity for Kepler Targets. II. G and F Main-sequence Stars and Cool Subgiant Stars 2021ApJS..255...17S
    TOI-220 b: a warm sub-Neptune discovered by TESS 2021MNRAS.505.3361H
    Hot planets around cool stars - two short-period mini-Neptunes transiting the late K-dwarf TOI-1260 2021MNRAS.505.4684G
    Magnetic signatures on mixed-mode frequencies. I. An axisymmetric fossil field inside the core of red giants 2021A&A...650A..53B
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    Componentes del experimento PLATO
    PLATO (PLAnetary Transits and Oscillations of stars)
    PLAnetary Transits and Oscillations of stars (PLATO) is the third medium-class mission in ESA's Cosmic Vision programme. Its objective is to find and study a large number of extrasolar planetary systems, with emphasis on the properties of terrestrial planets in the habitable zone around solar-like stars
    Hans Jörg
    Deeg Deeg