A5085906519- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Chaos control and synchronization
- Galaxies: Formation, Evolution, Phenomena
- Solar and Space Plasma Dynamics
- Biomedical and Engineering Education
- Environmental Impact and Sustainability
- Scientific Computing and Data Management
- Technology Assessment and Management
- Adaptive optics and wavefront sensing
- Statistical Mechanics and Entropy
- CCD and CMOS Imaging Sensors
Instituto de Astrofísica de Andalucía
2013-2023
Laboratoire d’Astrophysique de Marseille
2010
The growth of galaxies is one the key problems in understanding structure and evolution universe its constituents. Galaxies can grow their stellar mass by accretion halo or intergalactic gas clouds, merging with smaller similar galaxies. available translates into a rate star formation, which controls generation metals universe. spatially resolved history assembly has not been obtained so far for any given galaxy beyond Local Group. Here we demonstrate how massive inside-out. We report...
Planets orbiting low-mass stars such as M dwarfs are now considered a cornerstone in the search for life-harbouring planets. GJ273 is planetary system an dwarf only 3.75 pc away, composed of two confirmed planets, GJ273b and GJ273c, promising candidates, GJ273d GJ273e. Planet resides habitable zone. Currently, due to lack observed transits, minimum masses planets known.Despite being interesting system, still poorly studied. We aim at precisely determine physical parameters individual...
Several planetary formation models have been proposed to explain the observed abundance and variety of compositions super-Earths mini-Neptunes. In this context, multitransiting systems orbiting low-mass stars whose planets are close radius valley benchmark systems, which help elucidate model dominates. We report discovery, validation, initial characterization one such system, TOI-2096, composed a super-Earth mini-Neptune hosted by mid-type M dwarf located 48 pc away. first characterized host...
Aims. We study the theoretical properties of regular spacings found in oscillation spectra δ Scuti stars.
Aims. The aim of this work was to use a multi-approach technique derive the most accurate values possible physical parameters δ Sct star HD 174966, which observed with CoRoT satellite. In addition, we searched for periodic pattern in frequency spectra goal using it determine mean density star.
ABSTRACT We present the first asteroseismic results for δ Scuti and γ Doradus stars observed in Sectors 1 2 of TESS mission. utilize 2-min cadence data a sample 117 to classify their behaviour regarding variability place them Hertzsprung–Russell diagram using Gaia DR2 data. Included within our are eponymous members two pulsator classes, SX Phoenicis. Our pulsating intermediate-mass by also allows us confront theoretical models pulsation driving classical instability strip time show that...
ABSTRACT In this work, we aim at constraining the age of young open cluster Melotte 20, known as α Per, using seismic indices. The method consists following steps: (1) Extract frequency content a sample stars in field an cluster. (2) Search for possible regularities spectra δ Sct candidates, different techniques, such Fourier transform, autocorrelation function, histogram differences and échelle diagram. (3) Constrain selected by both physical parameters indices comparing them with grid...
Detecting and understanding rotation in stellar interiors is nowadays one of the unsolved problems physics. Asteroseismology has been able to provide insights on for Sun, solar-like stars, compact objects like white dwarfs. However, this still very difficult intermediate-mass stars. These stars are moderate-to-rapid rotators. Rotation splits shifts oscillation modes, which makes spectrum more complex harder interpret. Here we study patterns a sample benchmark $δ$~Sct belonging eclipsing...
It is known that the observed distribution of frequencies in CoRoT and Kepler {\delta} Scuti stars has no parallelism with any theoretical model. Pre-whitening a widespread technique analysis time series gaps from pulsating located classical instability strip such as stars. However, some studies have pointed out this might introduce biases results frequency analysis. This work aims at studying can result pre-whitening asteroseismology. The will depend on intrinsic range periodic nature...
ABSTRACT Fractal fingerprints have been found recently in the light curves of several δ Scuti stars observed by Convection Rotation and planetary Transits(CoRoT) satellite. This sole fact might pose a problem for detection pulsation frequencies using classical pre-whitening techniques, but it is also potentially rich source information about physical mechanisms associated with stellar variability. Assuming that curve composed superposition oscillation modes fractal background noise, this...
The large separation in the low radial order regime is considered as a highly valuable observable to derive mean densities of $\delta$ Scuti stars, due its independence with rotation. Up now, theoretical studies this $\Delta\nu$-${\bar \rho}$ relation have been limited 1D non-rotating models, and 2D pseudo-evolutionary models. present work aims at completing scenario by investigating quantitatively impact rotation on grid asteroseismic models representative stars. These include effects both...
Several planetary formation models have been proposed to explain the observed abundance and variety of compositions super-Earths mini-Neptunes. In this context, multitransiting systems orbiting low-mass stars whose planets are close radius valley benchmark systems, which help elucidate model dominates. We report discovery, validation, initial characterization one such system, TOI-2096, composed a super-Earth mini-Neptune hosted by mid-type M dwarf located 48 pc away. first characterized host...
Abstract We study the theoretical properties of regular spacings found in oscillation spectra δ Scuti stars. A linear relation between large separation and mean density is predicted to be low-frequency domain (i.e. radial orders spanning from 1 8, approximately) main-sequence stars' spectrum. This implies an independent direct measure average stars, analogous that Sun, places tight constraints on mode identification hence stellar internal structure dynamics, allows a determination radii...
This paper aims at being a provocative guide to the future of asteroseismology from perspective analysis time series, where fundamentals harmonic are subjected stress tests. In this context, we give an annotated summary our research over last decades on A-F stars. We discuss and explore consequences findings, which may extend any kind pulsators. As well, analyse impact reconsideration asteroseismic studies, would entail paradigm shift. includes discussion presence fractal behaviour in δ Sct...
Fractal fingerprints have been found recently in the light curves of several {\delta} Scuti stars observed by CoRoT satellite. This sole fact might pose a problem for detection pulsation frequencies using classical pre-whitening techniques, but it is also potentially rich source information about physical mechanisms associated to stellar variability. Assuming that curve composed superposition oscillation modes with fractal background noise, this work we applied Coarse Graining Spectral...