Line-profile variations of stochastically excited oscillations in four evolved stars

  title={Line-profile variations of stochastically excited oscillations in four evolved stars},
  author={Saskia Hekker and Conny Aerts},
  journal={Astronomy and Astrophysics},
Context. Since solar-like oscillations were first detected in red-giant stars, the presence of non-radial oscillation modes has been debated. Spectroscopic line-profile analysis was used in the first attempt to perform mode identification, which revealed that non-radial modes are observable. Despite the fact that the presence of non-radial modes could be confirmed, the degree or azimuthal order could not be uniquely identified. Here we present an improvement to this first spectroscopic line… 

Detection of solar-like oscillations in the bright red giant stars γ Piscium and θ1 Tauri from a 190-day high-precision spectroscopic multi-site campaign⋆

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Observations and interpretation of solar-like oscillations in red-giant stars

Over the past decade the study of solar-like oscillations in red-giant stars has developed significantly. Not only the number of red-giant stars for which solar-like oscillations have been observed


The basic mechanisms responsible for producing winds from cool, late-type stars are still largely unknown. We take inspiration from recent progress in understanding solar wind acceleration to develop

Giant star seismology

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The Star–Planet Connection. I. Using Stellar Composition to Observationally Constrain Planetary Mineralogy for the 10 Closest Stars

The compositions of stars and planets are connected, but the definition of “habitability” and the “habitable zone” only take into account the physical relationship between the star and planet.

Asteroseismic modelling of the solar-type subgiant star β Hydri

Context. Comparing models and data of pulsating stars is a powerful way to understand the stellar structure better. Moreover, such comparisons are necessary to make improvements to the physics of the

The IACOB project: III. New observational clues to understand macroturbulent broadening in massive O- and B-type stars ?

Context. The term macroturbulent broadening is commonly used to refer to a certain type of non-rotational broadening affecting the spectral line profiles of O- and B-type stars. It has been proposed



Theoretical amplitudes and lifetimes of non-radial solar-like oscillations in red giants

Context. Solar-like oscillations have been observed in numerous red giants from ground and from space. An important question arises: could we expect to detect non-radial modes probing the internal

Pulsations detected in the line profile variations of red giants. Modelling of line moments, line bisector and line shape

Observatoire de Gene`ve, 51 chemin de Maillettes, 1290 Sauverny, SwitzerlandReceived idate?; accepted idate?ABSTRACTContext. So far, red giant oscillations have been studied from radial velocity

Oscillations of α UMa and other red giants

There is growing observational evidence that the variability of red giants could be caused by self-excitation of global modes of oscillation. The most recent evidence of such oscillations was

A new method for the spectroscopic identification of stellar non-radial pulsation modes. I. The meth

Aims. We present the Fourier parameter fit method, a new method for spectroscopically identifying stellar radial and non-radial pulsation modes based on the high-resolution time-series spectroscopy

Detection of solar-like oscillations in the red giant star $\epsilon$ Ophiuchi by MOST spacebased photometry

Context. Solar-like oscillations have been discovered in a few red giants, including ϵ  Oph, through spectroscopy. Acoustic modes around 60  μ Hz were clearly seen in this star, but daily aliasing of

Non-radial oscillation modes with long lifetimes in giant stars

The presence of radial and non-radial oscillations in more than 300 giant stars is reported, finding giant stars with equally spaced frequency peaks in the Fourier spectrum of the time series, as well as giants for which the spectrum seems to be more complex.


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

Solar-like Oscillations in the G2 Subgiant β Hydri from Dual-Site Observations

We have observed oscillations in the nearby G2 subgiant star β Hyi using high-precision velocity observations obtained over more than a week with the HARPS and UCLES spectrographs. The oscillation

Precise radial velocities of giant stars. III. Spectroscopic stellar parameters

Context. A radial velocity survey of about 380 G and K giant stars is ongoing at Lick observatory. For each star we have a high signal to noise ratio template spectrum, which we use to determine

Nonradial p-modes in the G9.5 giant $\epsilon$ Ophiuchi? Pulsation model fits to MOST photometry

The G9.5 giant ∈ Oph shows evidence of radial p-mode pulsations in both radial velocity and luminosity. We re-examine the observed frequencies in the photometry and radial velocities and find a best