Perturbations in the upper layers of α Centauri A

6th Nuclear Physics in Astrophysics

物理学;天文学

Brito, A.^1,2 ; Lopes, I.^1,3

CENTRA, Physics Department, Instituto Superior Técnico, Portugal^1

Departement of Mathematics, Instituto Superior de Gestão, Portugal^2

Department of Physics, University of Évora, Portugal^3

关键词: Asteroseismology;    Diagnostic tools;    External layers;    Internal structure;    Rapid variation;    Seismic parameters;    Stellar interior;    Strong scatterings;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/665/1/012081/pdf
DOI  :  10.1088/1742-6596/665/1/012081

学科分类：天文学(综合)

来源: IOP

【 摘 要 】

The emerging field of asteroseismology allows the direct study of stellar interiors with an incredibly high precision. We used a seismic parameter based on the phase shift as a diagnostic tool to infer the presence of a new layer of rapid variation in the external layers of the primary component of the stellar system Alpha Centauri AB. This layer is, apparently, a thin region where the acoustic modes suffer a strong scattering. Our tests indicate that this layer should be located at an acoustical depth of approximately 1400 s (0.939 R), which corresponds to a depth of 6% below the surface of the star. This is somehow unexpected since the internal structure of this sun-like star is predicted to be similar to the Sun.