English
Related papers

Related papers: Mixed Modes and Asteroseismic Surface Effects: I. …

200 papers

Models of solar-like oscillators yield acoustic modes at different frequencies than would be seen in actual stars possessing identical interior structure, due to modelling error near the surface. This asteroseismic "surface term" must be…

Solar and Stellar Astrophysics · Physics 2021-11-24 J. M. Joel Ong , Sarbani Basu , Mikkel N. Lund , Allyson Bieryla , Lucas S. Viani , David W. Latham

Localised modelling error in the near-surface layers of evolutionary stellar models causes the frequencies of their normal modes of oscillation to differ from those of actual stars with matching interior structures. These frequency…

Solar and Stellar Astrophysics · Physics 2021-01-13 J. M. Joel Ong , Sarbani Basu , Jean M. McKeever

Oscillation frequencies of even the best stellar models differ from those of the stars they represent, and the difference is predominantly a function of frequency. This difference is caused by limitations of modeling the near-surface layers…

Solar and Stellar Astrophysics · Physics 2018-12-12 Sarbani Basu , Archer Kinnane

Inaccurate modelling of the near-surface layers of solar models causes a systematic difference between modelled and observed solar mode frequencies. This difference---known as the "surface effect" or "surface term"---presumably also exists…

Solar and Stellar Astrophysics · Physics 2017-11-07 Warrick H. Ball

In asteroseismology, the surface effect refers to a disparity between the observed and the modelled frequencies in stars with solar-like oscillations. It originates from improper modelling of the surface layers. Correcting the surface…

Accurate modelling of solar-like oscillators requires that modelled mode frequencies are corrected for the systematic shift caused by improper modelling of the near-surface layers, known as the surface effect. ... We investigate how much…

Solar and Stellar Astrophysics · Physics 2017-04-19 W. H. Ball , L. Gizon

Asteroseismology is a powerful tool that can precisely characterize the mass, radius, and other properties of field stars. However, our inability to properly model the near-surface layers of stars creates a frequency-dependent frequency…

Solar and Stellar Astrophysics · Physics 2015-08-06 Joseph R. Schmitt , Sarbani Basu

... [C]urrent stellar models predict oscillation frequencies that are systematically affected by simplified modelling of the near-surface layers. We use three-dimensional radiation hydrodynamics simulations to better model the near-surface…

Solar and Stellar Astrophysics · Physics 2016-08-31 W. H. Ball , B. Beeck , R. H. Cameron , L. Gizon

Asteroseismology has been used extensively in recent years to study the interior structure and physical processes of main sequence stars. We consider prospects for using pressure modes (p-modes) near the frequency of maximum oscillation…

Solar and Stellar Astrophysics · Physics 2023-06-14 Christopher J. Lindsay , J. M. Joel Ong , Sarbani Basu

Acoustic modes of oscillation are affected by stellar activity, however it is unclear how starspots contribute to these changes. Here we investigate the nonmagnetic effects of starspots on global modes with angular degree $\ell \leq 2$ in…

Solar and Stellar Astrophysics · Physics 2015-05-20 Emanuele Papini , Aaron C. Birch , Laurent Gizon , Shravan M. Hanasoge

In helioseismology, there is a well-known offset between observed and computed oscillation frequencies. This offset is known to arise from improper modeling of the near-surface layers of the Sun, and a similar effect must occur for models…

Astrophysics · Physics 2009-11-13 Hans Kjeldsen , Timothy R. Bedding , Joergen Christensen-Dalsgaard

The theoretical oscillation frequencies of even the best asteroseismic models of solar-like oscillators show significant differences from observed oscillation frequencies. Structure inversions seek to use these frequency differences to…

Solar and Stellar Astrophysics · Physics 2024-02-02 Lynn Buchele , Earl P. Bellinger , Saskia Hekker , Sarbani Basu , Warrick Ball , Jørgen Christensen-Dalsgaard

Theoretical works have looked into the various topologies and amplitudes, as well as the stability of the magnetic field that is expected to be present in the radiative interior of stars evolving after the main sequence. Such internal…

Solar and Stellar Astrophysics · Physics 2022-11-09 L. Bugnet

Constraining stellar models using asteroseismic and spectroscopic observations is a powerful method for precisely determining the fundamental properties of stars in different kinematic components of our galaxy. We use spectroscopy and…

Solar and Stellar Astrophysics · Physics 2026-03-05 Christopher J. Lindsay , J. M. Joel Ong , Sarbani Basu , Samuel Grunblatt , Marc Hon

Asteroseismology, i.e. the study of the internal structures of stars via their global oscillations, is a valuable tool to obtain stellar parameters such as mass, radius, surface gravity and mean density. These parameters can be obtained…

Solar and Stellar Astrophysics · Physics 2015-06-16 S. Hekker , Y. Elsworth , S. Basu , A. Mazumdar , V. Silva Aguirre , W. J. Chaplin

Oscillation mode frequencies of stars are typically treated as static for a given stellar model. However, in reality they can be perturbed by time varying sources such as magnetic fields and flows. We calculate the sensitivities of radial…

Solar and Stellar Astrophysics · Physics 2020-07-01 René Kiefer , Anne-Marie Broomhall

Poor modelling of the surface regions of solar-like stars causes a systematic discrepancy between the observed and model pulsation frequencies. We aim to characterise this frequency discrepancy for main sequence solar-like oscillators for a…

Solar and Stellar Astrophysics · Physics 2018-06-28 D. L. Compton , T. R. Bedding , W. H. Ball , D. Stello , D. Huber , T. R. White , H. Kjeldsen

The solar-cyle variation of acoustic mode frequencies has a frequency dependence related to the inverse mode inertia. The discrepancy between model predictions and measured oscillation frequencies for solar and solar-type stellar acoustic…

Solar and Stellar Astrophysics · Physics 2016-12-07 R. Howe , S. Basu , G. R. Davies , W. H. Ball , W. J. Chaplin , Y. Elsworth , R. Komm

Asteroseismology is a powerful way of determining stellar parameters and properties of stars like the Sun. However, main-sequence F-type stars exhibit short mode lifetimes relative to their oscillation frequency, resulting in overlapping…

Solar and Stellar Astrophysics · Physics 2019-02-18 Douglas L. Compton , Timothy R. Bedding , Dennis Stello

Asteroseismology is our only means of measuring stellar rotation in their interiors, rather than at their surfaces. Some techniques for measurements of this kind -- "rotational inversions" -- require the shapes of linear response kernels…

Solar and Stellar Astrophysics · Physics 2023-11-14 J. M. Joel Ong
‹ Prev 1 2 3 10 Next ›