Expanding the frontiers of cool-dwarf asteroseismology with ESPRESSO

• Tipo: Artigo em Revista Científica Internacional
• Data: 2024

Autores

Campante, TL (Autor) FCUP; Kjeldsen, H (Autor) Outra; Li, Y (Autor) Outra; Lund, MN (Autor) Outra; Silva, AM (Autor) Outra; Corsaro, E (Autor) Outra; da Silva, JG (Autor) Outra; Martins, JHC (Autor) Outra; Adibekyan, V (Autor) Outra; Silva, TA (Autor) Outra; Bedding, TR (Autor) Outra; Bossini, D (Autor) Outra; Buzasi, DL (Autor) Outra; Chaplin, WJ (Autor) Outra; Costa, RR (Autor) Outra; Cunha, MS (Autor) FCUP; Cristo, E (Autor) Outra; Faria, JP (Autor) Outra; Garcia, RA (Autor) Outra; Huber, D (Autor) Outra; Lundkvist, MS (Autor) Outra; Metcalfe, TS (Autor) Outra; Monteiro, MJPFG (Autor) FCUP; Neitzel, AW (Autor) Outra; Nielsen, MB (Autor) Outra; Poretti, E (Autor) Outra; N.C. Santos (Autor) FCUP; Sousa, SG (Autor) FCUP

Revista

Título: Astronomy and Astrophysics

Vol. 683

Página Final: L16

ISSN: 0004-6361

Editora: EDP Sciences

Indexação

ISI Web of Knowledge - 0 Citações

Scopus - 1 Citação

Outras Informações

ID Authenticus: P-010-8R5

DOI: 10.1051/0004-6361/202449197

Abstract (EN): Fuelled by space photometry, asteroseismology is vastly benefitting the study of cool main-sequence stars, which exhibit convection-driven solar-like oscillations. Even so, the tiny oscillation amplitudes in K dwarfs continue to pose a challenge to space-based asteroseismology. A viable alternative is offered by the lower stellar noise over the oscillation timescales in Doppler observations. In this Letter we present the definite detection of solar-like oscillations in the bright K5 dwarf & varepsilon; Indi based on time-intensive observations collected with the ESPRESSO spectrograph at the VLT, thus making it the coolest seismic dwarf ever observed. We measured the frequencies of a total of 19 modes of degree & ell; = 0-2 along with nu(max) = 5305 +/- 176 mu Hz and Delta nu = 201.25 +/- 0.16 mu Hz. The peak amplitude of radial modes is 2.6 +/- 0.5 cm s(-1), or a mere similar to 14% of the solar value. Measured mode amplitudes are similar to 2 times lower than predicted from a nominal L/M scaling relation and favour a scaling closer to (L/M)(1.5) below similar to 5500 K, carrying important implications for our understanding of the coupling efficiency between pulsations and near-surface convection in K dwarfs. This detection conclusively shows that precise asteroseismology of cool dwarfs is possible down to at least the mid-K regime using next-generation spectrographs on large-aperture telescopes, effectively opening up a new domain in observational asteroseismology.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10