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Related papers: Solar-like oscillations in the G2 subgiant beta Hy…

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We have made a clear detection of excess power, providing strong evidence for solar-like oscillations in the G2 subgiant beta Hyi. We observed this star over five nights with the UCLES echelle spectrograph on the 3.9-m Anglo-Australian…

Velocity measurements of the G2 subgiant beta Hyi with both UCLES and CORALIE show a clear excess of power centred at 1.0 mHz. In the UCLES data we find evidence for a short-lived, high-amplitude oscillation event. If confirmed as a feature…

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of beta Hydri. This star is a nearby G2 subgiant whose mean density was recently measured with high precision using asteroseismology. We…

We have made velocity observations of the star alpha Cen B from two sites, allowing us to identify 37 oscillation modes with l=0-3. Fitting to these modes gives the large and small frequency separations as a function of frequency. The mode…

The solar-type subgiant $\beta$ Hyi has long been studied as an old analog of the Sun. Although the rotation period has never been measured directly, it was estimated to be near 27 days. As a southern hemisphere target it was not monitored…

We used HARPS to measure oscillations in the low-mass star tau Cet. Although the data were compromised by instrumental noise, we have been able to extract the main features of the oscillations. We found tau Cet to oscillate with an…

We report the firm discovery of solar-like oscillations in a giant star. We monitored the star xi Hya (G7III) continuously during one month with the CORALIE spectrograph attached to the 1.2m Swiss Euler telescope. The 433 high-precision…

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

Aims: From observations of the K4III star Beta UMi we attempt to determine whether oscillations or any other form of variability is present. Methods: A high-quality photometric time series of approximately 1000 days in length obtained from…

Astrophysics · Physics 2009-11-13 N. J. Tarrant , W. J. Chaplin , Y. Elsworth , S. A. Spreckley , I. R. Stevens

We present the results of modelling the subgiant star $\beta$ Hydri using the seismic observational constraints. We have computed several grids of stellar evolutionary tracks using Aarhus STellar Evolution Code (ASTEC,…

Solar and Stellar Astrophysics · Physics 2011-03-28 G. Doğan , I. M. Brandão , T. R. Bedding , J. Christensen-Dalsgaard , M. S. Cunha , H. Kjeldsen

We introduce a new method to measure frequency separations and mode lifetimes of stochastically excited and damped oscillations, so-called solar-like oscillations. Our method shows that velocity data of the red giant star ksi Hya (Frandsen…

Astrophysics · Physics 2009-11-11 D. Stello , H. Kjeldsen , T. R. Bedding , D. Buzasi

A clear detection of excess of power, providing a substantial evidence for solar-like oscillations in the G5 subgiant \muher{}, is presented. This star was observed over seven nights with the SARG echelle spectrograph operating with the…

Astrophysics · Physics 2009-11-13 A. Bonanno , S. Benatti , R. Claudi , S. Desidera , R. Gratton , S. Leccia , L. Paterno'

p-mode oscillations in solar-like stars are excited by the outer convection zone in these stars and reflected close to the surface. The p-modes are trapped inside an acoustic cavity, but the modes only stay trapped up to a given frequency…

Astrophysics · Physics 2009-11-13 C. Karoff

We obtained time-series spectroscopy of the G0 subgiant eta Boo in an attempt to confirm the solar-like oscillations reported by Kjeldsen et al. (1995). We recorded 1843 spectra over six consecutive nights with the Nordic Optical Telescope,…

Observations of stellar activity cycles provide an opportunity to study magnetic dynamos under many different physical conditions. Space-based asteroseismology missions will soon yield useful constraints on the interior conditions that…

Astrophysics · Physics 2009-06-23 T. S. Metcalfe , W. A. Dziembowski , P. G. Judge , M. Snow

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

We have measured solar-like oscillations in red giants using time-series photometry from the first 34 days of science operations of the Kepler Mission. The light curves, obtained with 30-minute sampling, reveal clear oscillations in a large…

Oscillations in solar-like oscillators tend to follow an approximately regular pattern in which oscillation modes of a certain degree and consecutive order appear at regular intervals in frequency, i.e. the so-called large frequency…

Solar and Stellar Astrophysics · Physics 2015-06-04 S. Hekker , Sarbani Basu , Y. Elsworth , W. J. Chaplin

We have observed evidence for $p$-mode oscillations in the G0 IV star etaBoo (V = 2.68). This represents the first clear evidence of solar-like oscillations in a star other than the Sun. We used a new technique which measures fluctuations…

Astrophysics · Physics 2009-10-22 Hans Kjeldsen , Timothy R. Bedding , Michael Viskum , Soeren Frandsen

The stellar companions in the binary black hole systems Gaia BH2 and BH3, both of which are $\alpha$-enhanced red giant branch stars, are expected to show normal modes with the characteristic signature of convectively-driven solar-like…

Solar and Stellar Astrophysics · Physics 2025-09-11 Daniel Hey , Yaguang Li , Joel Ong
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