Related papers: P-mode observations on Alpha Cen A

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,…

MOST observations and model analysis of the Herbig Ae star HD 34282 (V1366 Ori) reveal {\delta}-Scuti pulsations. 22 frequencies are observed, 10 of which confirm those previously identified by Amado et al. (2006), and 12 of which are newly…

High quality observations of the low-degree acoustic modes (p-modes) exist for almost two complete solar cycles using the solar spectrophotometer Mark-I, located at the Observatorio del Teide (Tenerife, Spain) and operating now as part of…

We present the results of a long-term monitoring campaign of the H\alpha line in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting rotationally modulated changes potentially related to the existence of large-scale wind…

We present bisector measurements of the H-alpha line of the rapidly oscillating Ap (roAp) star, Alpha-Cir, obtained from dual-site observations with medium-dispersion spectrographs. The velocity amplitude and phase of the principal…

We present the results from 135 hours of nearly continuous time series photometry on the ``hybrid'' (H-rich) PG1159 variable star HS2324+3944, obtained in August-September 1997. The power spectrum of the data shows several frequencies…

Successful inference from asteroseismology relies on at least two things: that the oscillations in the stars have amplitudes large enough to be clearly observable; and that the oscillations themselves be stable enough to enable precise…

Oscillation mode frequencies of stars are typically treated as static for a given stellar model. However, in reality they can be perturbed by time varying sources such as magnetic fields and flows. We calculate the sensitivities of radial…

We report a multisite photometric campaign for the Beta Cephei star 12 Lacertae. 750 hours of high-quality differential photoelectric Stromgren, Johnson and Geneva time-series photometry were obtained with 9 telescopes during 190 nights.…

We recently announced the detection of an unknown submillimeter source in our ALMA observations of alpha Cen AB. The source was detected in two epochs, a strong detection at 445~GHz and one at lower significance at 343.5~GHz. After valuable…

We used long duration, high quality, unresolved (Sun-as-a star) observations collected by the ground based network BiSON and by the instruments GOLF and VIRGO on board the ESA/NASA SOHO satellite to search for solar-cycle-related changes in…

To expand the range in the colour-magnitude diagram where asteroseismology can be applied, we organized a photometry campaign to find evidence for solar-like oscillations in giant stars in the globular cluster M4. The aim was to detect the…

The Microvariability and Oscillations of STars (MOST) photometric satellite has already undertaken more than 64 primary campaigns which include some clusters and has obtained observations of >850 secondary stars of which ~180 are variable.…

Oscillations were observed across the whole solar disk using the Doppler shift and line depth of spectral lines from the CO molecule near 4666~nm with the National Solar Observatory's McMath/Pierce solar telescope. Power, coherence, and…

We use the traditional approximation to describe oscillations with frequencies comparable to the angular rotation rate. Validity of this approximation in application to main-sequence B stars is discussed. Numerical results regarding mode…

Context: The F8 star HD 181906 (effective temperature ~6300K) was observed for 156 days by the CoRoT satellite during the first long run in the centre direction. Analysis of the data reveals a spectrum of solar-like acoustic oscillations.…

Spectral energy distributions are computed using 2D rotating stellar models and NLTE plane parallel model atmospheres. A rotating, 2D stellar model has been found which matches the observed ultraviolet and visible spectrum of ? Oph. The SED…

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…

We study the Be star $\delta$ Cen circumstellar disk using long-baseline interferometry which is the only observing technique capable of resolving spatially and spectroscopically objects smaller than 5 mas in the H and K b and. We used the…

We analyze more than 5000 days of high-quality Sun-as-a-star, radial velocity GOLF and photometric VIRGO/SPM helioseismic observations to extract precise estimates of the visibilities of the low-degree p modes and the m-height ratios of the…