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Related papers: Solar-like oscillations in alpha Centauri B

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Adiabatic oscillation frequencies of stellar models, computed with the standard mixing-length formulation for convection, increasingly deviate with radial order from observations in solar-like stars. Standard solar models overestimate…

Solar and Stellar Astrophysics · Physics 2016-11-15 G. Houdek , R. Trampedach , M. J. Aarslev , J. Christensen-Dalsgaard

Seismology of stars provides insight into the physical mechanisms taking place in their interior, with modes of oscillation probing different layers. Low-amplitude acoustic oscillations excited by turbulent convection were detected four…

Observations of the red giant Arcturus (Alpha Boo) obtained with the star tracker on the Wide Field Infrared Explorer (WIRE) satellite during a baseline of 19 successive days in 2000 July-August are analysed. The power spectrum has a…

Astrophysics · Physics 2007-05-23 Alon Retter , Timothy R. Bedding , Derek Buzasi , Hans Kjeldsen

Aims. With the Solar Optical Telescope on Hinode, we investigate the basic properties of high-degree solar oscillations observed at two levels in the solar atmosphere, in the G-band (formed in the photosphere) and in the Ca II H line…

Astrophysics · Physics 2009-11-13 U. Mitra-Kraev , A. G. Kosovichev , T. Sekii

Properties of stars undergoing pulsation such as the well known root-mean-density scaling relation can be useful when trying to match the observed properties of a particular star. It is often assumed that this relation is valid for p mode…

Solar and Stellar Astrophysics · Physics 2016-04-27 Diego Castañeda , Robert G. Deupree

Context. An analysis of the oscillations above sunspots was carried out using simultaneous ground-based and Solar Dynamics Observatory (SDO) observations (SiI 10827A, HeI 10830A, FeI 6173A, 1700A, HeII 304A, FeIX 171A). Aims. Investigation…

Solar and Stellar Astrophysics · Physics 2014-11-25 N. I. Kobanov , A. A. Chelpanov , D. Y. Kolobov

We present first results from five XMM-Newton observations of the binary system Alpha Centauri, which has been observed in snapshot like exposures of roughly two hours each during the last two years. In all our observations the X-ray…

Astrophysics · Physics 2009-11-11 J. Robrade , J. H. M. M. Schmitt , F. Favata

Adiabatic modeling of solar-like oscillations cannot exceed a certain level of precision for fitting individual frequencies. This is known as the problem of near surface effects on the mode physics. We present a theoretical study which…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. Grigahcène , M. -A. Dupret , S. G. Sousa , M. J. P. F. G. Monteiro , R. Garrido , R. Scuflaire , M. Gabriel

We recently reported strong evidence for solar-like oscillations in the G0 IV star eta Boo (Kjeldsen et al. 1995, AJ 109, 1313). We measured small temperature fluctuations produced by oscillations through their effect on the equivalent…

Astrophysics · Physics 2016-08-30 T. R. Bedding , H. Kjeldsen

For the very best and brightest asteroseismic solar-type targets observed by Kepler, the frequency precision is sufficient to determine the acoustic depths of the surface convective layer and the helium ionization zone. Such sharp features…

Oscillation properties are usually measured by fitting symmetric Lorentzian profiles to the power spectra of Sun-like stars. However the line profiles of solar oscillations have been observed to be asymmetrical for the Sun. The physical…

Solar and Stellar Astrophysics · Physics 2018-05-02 O. Benomar , Mjo. Goupil , K. Belkacem , T. Appourchaux , M. B. Nielsen , M. Bazot , L. Gizon , S. Hanasoge , K. R. Sreenivasan , B. Marchand

The rich acoustic oscillation spectrum in solar-type variables make these stars particularly interesting for studying fluid-dynamical aspects of the stellar interior. I present a summary of the properties of solar-like oscillations, how…

Solar and Stellar Astrophysics · Physics 2014-11-20 Gunter Houdek

RCB stars are $L\approx10^4\,L_{\odot}$ solar-mass objects that can exhibit large periods of extinction from dust ejection episodes. Many exhibit semiregular pulsations in the range of $30-50$ days with semi-amplitudes of $0.05-0.3$…

Solar and Stellar Astrophysics · Physics 2023-11-20 Tin Long Sunny Wong , Lars Bildsten

We have analysed oscillations of the red giant star HD 186355 observed by the NASA Kepler satellite. The data consist of the first five quarters of science operations of Kepler, which cover about 13 months. The high-precision time-series…

The measured properties of stellar oscillations can provide powerful constraints on the internal structure and composition of stars. To begin this process, oscillation frequencies must be extracted from the observational data, typically…

Solar and Stellar Astrophysics · Physics 2009-11-13 Brendon J. Brewer , Dennis Stello

Comparing models and data of pulsating stars is a powerful way to understand the stellar structure better.\beta Hyi is an evolved solar-type pulsator with mixed modes in its frequency spectrum, making it very interesting for asteroseismic…

Solar and Stellar Astrophysics · Physics 2015-05-20 I. M. Brandão , G. Dogan , J. Christensen-Dalsgaard , M. S. Cunha , T. R. Bedding , T. S. Metcalfe , H. Kjeldsen , H. Bruntt , T. Arentoft

We present the first observational evidence of multiple slow acoustic oscillations in the post flaring loops of the corona of Proxima Centauri using XMM-Newton observations. We find the signature of periodic oscillations localized in the…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. K. Srivastava , S. Lalitha , J. C. Pandey

In solar-like stars, acoustic modes provide the main way of probing their internal structure and dynamics. Although these modes are expected to be ubiquitous in stars with convective envelopes, Kepler observations reveal that a significant…

Solar and Stellar Astrophysics · Physics 2026-04-30 Arthur Le Saux , Leïla Bessila , Stéphane Mathis

In the present work, we study correlations between stellar fundamental parameters and the oscillation amplitude for delta Scuti stars. We present this study for a sample of 17 selected delta Scuti stars belonging to 5 young open clusters.…

Astrophysics · Physics 2009-11-07 J. C. Suarez , E. Michel , F. Perez Hernandez , Y. Lebreton , Z. P. Li , L. Fox Machado