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Related papers: Seismic detection of stellar tachoclines

200 papers

The observed solar oscillation spectrum is influenced by internal perturbations such as flows and structural asphericities. These features induce splitting of characteristic frequencies and distort the resonant-mode eigenfunctions. Global…

Solar and Stellar Astrophysics · Physics 2023-04-26 Srijan Bharati Das , Samarth G. Kashyap , Deniz Oktay , Shravan M. Hanasoge , Jeroen Tromp

High precision and long-lasting \emph{Kepler} data enabled us to estimate stellar properties with asteroseismology as an accurate tool. We performed asteroseismic analysis on six solar-like stars observed by the \emph{Kepler} mission: KIC…

Solar and Stellar Astrophysics · Physics 2017-05-23 Yaguang Li , Minghao Du , Bohan Xie , Zhijia Tian , Shaolan Bi , Tanda Li , Yaqian Wu , Kang Liu

In recent years there has been some progress towards detecting solar-like oscillations in stars. The goal of this challenging project is to analyse frequency spectra similar to that observed for the Sun in integrated light. In this context…

Astrophysics · Physics 2009-10-30 F. Perez Hernandez , J. Christensen-Dalsgaard

Differential rotation is central to a great many mysteries in stars and planets. In Part I we predicted the order of magnitude and scaling of the differential rotation in both hydrodynamic and magnetohydrodynamic convection zones. Our…

Solar and Stellar Astrophysics · Physics 2020-09-02 Adam S. Jermyn , Shashikumar M. Chitre , Pierre Lesaffre , Christopher A. Tout

We present an analytical model for the transmission spectrum of a transiting exoplanet, showing that a cloud base can produce an observable inflection point in the spectrum. The wavelength and magnitude of the inflection can be used to…

Earth and Planetary Astrophysics · Physics 2014-06-17 Sanaz Vahidinia , Jeffrey N. Cuzzi , Mark Marley , Jonathan Fortney

The study of stellar oscillations - asteroseismology - has revolutionized our understanding of the physical properties of the Sun, and similar potential for other stars has been demonstrated in recent years. In particular, asteroseismic…

Astrophysics · Physics 2007-05-23 D. Stello , H. Kjeldsen , T. R. Bedding

We perform helioseismic holography on realistic solar convection simulations and compare the observed travel-time perturbations with the expected travel times from the horizontal flows in the simulations computed from forward models under…

Astrophysics · Physics 2016-03-28 D. C. Braun , A. C. Birch , D. Benson , R. F. Stein , Å. Nordlund

We quantify the effect of observational spectroscopic and asteroseismic uncertainties on regularised least squares (RLS) inversions for the radial differential rotation of Sun-like and subgiant stars. We first solved the forward problem to…

Solar and Stellar Astrophysics · Physics 2016-01-27 Hannah Schunker , Jesper Schou , Warrick H. Ball

Recent analyses of the helioseismic data have produced evidence for a variety of interesting dynamical behaviour associated with torsional oscillations. What is not so far clear is whether these oscillations extend all the way to the bottom…

Astrophysics · Physics 2009-11-07 Reza Tavakol , Eurico Covas , David Moss , Andrew Tworkowski

Recent analyses of the helioseismic observations indicate that the previously observed surface torsional oscillations with periods of about 11 years extend significantly downwards into the solar convective zone. Furthermore, there are…

Astrophysics · Physics 2007-05-23 Eurico Covas , Reza Tavakol , David Moss

Almost 100 years ago Sir Arthur Eddington noted that the interiors of stars were inaccessible to observations. The advent of helio- and asteroseismology has completely changed this assessment. Helioseismology has provided very detailed…

Solar and Stellar Astrophysics · Physics 2016-02-23 J. Christensen-Dalsgaard

We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. M. Hanasoge , T. L. Duvall , M. L. DeRosa

The stable oscillations of pulsating stars can serve as accurate timepieces, which may be monitored for the influence of exoplanets. An external companion gravitationally tugs the host star, causing periodic changes in pulsation arrival…

Solar and Stellar Astrophysics · Physics 2019-02-06 J. J. Hermes

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

Rapidly rotating stars show short-period oscillations in magnetic activity and polar appearance of starspots. The aim of this paper is to study large-scale shallow water waves in the tachoclines of rapidly rotating stars and their…

Solar and Stellar Astrophysics · Physics 2015-05-28 T. V. Zaqarashvili , R. Oliver , J. L. Ballester , M. Carbonell , M. L. Khodachenko , H. Lammer , M. Leitzinger , P. Odert

The property of inhomogeneous turbulence in conducting fluids to expel large-scale magnetic fields in the direction of decreasing turbulence intensity is shown as important for the magnetic field dynamics near the base of a stellar…

Astrophysics · Physics 2009-11-13 L. L. Kitchatinov , G. Rüdiger

Useful information from the inner layers of stellar pulsators may be derived from the study of their oscillations. In this paper we analyse three diagnostic tools suggested in the literature built from the oscillation frequencies computed…

Solar and Stellar Astrophysics · Physics 2015-05-19 I. M. Brandão , M. S. Cunha , O. L. Creevey , J. Christensen-Dalsgaard

Many stars exhibit stellar pulsations, favoring them for asteroseismic analyses. Interpreting the oscillations requires some knowledge of the oscillation mode geometry (spherical degree, radial and azimuthal orders). The delta Scuti stars…

Solar and Stellar Astrophysics · Physics 2011-05-06 O. L. Creevey , T. S. Metcalfe , T. M. Brown , S. Jiménez-Reyes , J. A. Belmonte

Solar-like oscillations are excited stochastically by convection. They occur in stars with an outer convection zone, which includes the Sun and other stars on the lower main sequence, as well as cool subgiants and red giants. This chapter…

Solar and Stellar Astrophysics · Physics 2011-07-12 Timothy R. Bedding

The phenomenology associated with line profile variations in delta Scuti stars is reviewed. The three main techniques adopted to detect pulsation modes, i.e., the pixel-by-pixel analysis, the analysis of the moment time series and the…

Astrophysics · Physics 2007-05-23 L. Mantegazza