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Related papers: Solar-like oscillations in alpha Centauri B

200 papers

We present new spectroscopic and photometric time series observations of the delta Scuti star FG~Vir. We detect the oscillations via changes in the equivalent widths of hydrogen and metal absorption lines. From the ratios between…

Astrophysics · Physics 2007-05-23 M. Viskum , H. Kjeldsen , T. R. Bedding , T. H. Dall , I. K. Baldry , H. Bruntt , S. Frandsen

Solar-like oscillations have been observed by Kepler and CoRoT in many solar-type stars, thereby providing a way to probe the stars using asteroseismology. We provide the mode linewidths and mode heights of the oscillations of various stars…

A set of long and nearly continuous observations of alpha Centauri A should allow us to derive an accurate set of asteroseismic constraints to compare to models, and make inferences on the internal structure of our closest stellar…

Solar and Stellar Astrophysics · Physics 2015-05-19 P. de Meulenaer , F. Carrier , A. Miglio , T. R. Bedding , T. L. Campante , P. Eggenberger , H. Kjeldsen , J. Montalban

Convection in stars excites resonant acoustic waves. The frequencies of these oscillations depend on the sound speed inside the star, which in turn depends on density, temperature, gas motion, and other properties of the stellar interior.…

Astrophysics · Physics 2009-11-11 F. Carrier , P. Eggenberger

Kepler short-cadence photometry of 2347 stars with effective temperatures in the range 6000-10000 K was used to search for the presence of solar-like oscillations. The aim is to establish the location of the hot end of the stochastic…

Solar and Stellar Astrophysics · Physics 2020-08-17 L. A. Balona

We present a novel approach to model the nearby stars Alpha Cen A & B and Procyon A using asteroseismic and interferometric constraints. Using the VINCI instrument installed at the VLT Interferometer (VLTI), the angular diameters of the…

Astrophysics · Physics 2007-05-23 P. Kervella , F. Thevenin , P. Morel , G. Berthomieu , J. Provost , P. Borde , D. Segransan

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,…

Oscillation frequencies are the most accurate properties one can measure for a star, potentially allowing detailed tests of stellar models and evolution theories. We briefly review asteroseismology for two classes of stars. In delta Scuti…

Astrophysics · Physics 2007-05-23 Hans Kjeldsen , Timothy R. Bedding

Oscillations of the Sun and solar-like stars are believed to be excited stochastically by convection near the stellar surface. Theoretical modeling predicts that the resulting amplitude increases rapidly with the luminosity of the star.…

Astrophysics · Physics 2009-11-07 J. Christensen-Dalsgaard , H. Kjeldsen , J. A. Mattei

We present a new method for determining the location of active bands of latitude on solar-type stars, which uses stellar-cycle-induced frequency shifts of detectable solar-like oscillations. When near-surface activity is distributed in a…

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 determine the frequencies of solar oscillations covering a wide range of degree (100< l <4000) and frequency (1.5 <\nu<10 mHz) using the ring diagram technique applied to power spectra obtained from MDI (Michelson Doppler Imager) data.…

Astrophysics · Physics 2009-10-31 H. M. Antia , Sarbani Basu

Context. We present the first high-cadence multi-wavelength radial-velocity observations of the Sun-as-a-star, carried out during 57 consecutive days using the stellar \'echelle spectrograph at the Hertzsprung SONG Telescope operating at…

Context. The Sun and solar-like stars undergo activity cycles for which the underlying mechanisms are not well understood. The oscillations of the Sun are known to vary with its activity cycle and these changes provide diagnostics on the…

Solar and Stellar Astrophysics · Physics 2017-02-08 René Kiefer , Ariane Schad , Guy Davies , Markus Roth

We report on the first asteroseismic analysis of solar-type stars observed by Kepler. Observations of three G-type stars, made at one-minute cadence during the first 33.5d of science operations, reveal high signal-to-noise solar-like…

We present the analysis of time-resolved spectroscopy of the pulsating sdB star PG1605+072. From our main observing run of 16 nights we have detected velocity variations at 5 frequencies that correspond to those found in photometry. Based…

Astrophysics · Physics 2009-11-07 S. J. O'Toole , T. R. Bedding , H. Kjeldsen , T. H. Dall , D. Stello

Power spectra of the light curves of semiregular variables, based on visual magnitude estimates spanning many decades, show clear evidence for stochastic excitation. This supports the suggestion by Christensen-Dalsgaard et al. (2001) that…

Astrophysics · Physics 2007-05-23 Timothy R. Bedding

Over 2,000 stars were observed for one month with a high enough cadence in order to look for acoustic modes during the survey phase of the Kepler mission. Solar-like oscillations have been detected in about 540 stars. The question of why no…

Solar and Stellar Astrophysics · Physics 2019-07-03 S. Mathur , R. A. Garcia , L. Bugnet , A. R. G. Santos , N. Santiago , P. G. Beck

We present the analysis of 3 hrs of a rapid time series of precise stellar radial velocity (RV) measurements (sigma = 4.5 m/s) of the cool Ap star Beta CrB. The integrated RV measurements spanning the wavelength interval 5000-6000 Ang. show…

Astrophysics · Physics 2009-11-10 Artie P. Hatzes , David E. Mkrtichian