相关论文: Solar-like oscillations in semiregular variables
The CoRoT and Kepler space missions have detected oscillations in hundreds of Sun-like stars and thousands of field red-giant stars. This has opened the door to a new era of stellar population studies in the Milky Way. We report on the…
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 $0.05-0.3$…
We model the stochastic excitation of acoustic modes in solar-like pulsators taking into account the action of differential rotation. We derive the theoretical formalism for the stochastic excitation with differential rotation and make use…
Small cyclic variations in the frequencies of acoustic modes are expected to be a common phenomenon in solar-like pulsators, as a result of stellar magnetic activity cycles. The frequency variations observed throughout the solar and stellar…
Binary stars in which oscillations can be studied in either or both components can provide powerful constraints on our understanding of stellar physics. The bright binary 12 Bo\"otis (12 Boo) is a particularly promising system because the…
For the Sun, a tight correlation between various activity measures and oscillation frequencies is well documented. For other stars, we have abundant data on magnetic activity and its changes but not yet on its seismic signature. A…
Stochatic excitation of stellar oscillations by turbulent convection is investigated and an expression for the power injected into the oscillations by the turbulent convection of the outer layers is derived which takes into account…
We performed simple spot-model calculations for quasi-periodic brightness variations of solar-type stars showing superflares, by using Kepler photometric data. Most of superflare stars show quasi-periodic brightness modulations with the…
Measurements of oscillation frequencies of the Sun and stars can provide important independent constraints on their internal structure and dynamics. Seismic models of these oscillations are used to connect structure and rotation of the star…
Recent observations reveal the surprising breakdown of stellar gyrochronology relations at about the Sun's age hinting that middle-aged, solar-like stars transition to a magnetically inactive future. We provide a theoretical basis for these…
The Sun has long been considered a constant star, to the extent that its total irradiance was termed the solar constant. It required radiometers in space to detect the small variations in solar irradiance on timescales of the solar rotation…
After more than one year of operation, the Kepler photometer has already provided exquisite data of solar-type stars. During the survey phase, 42 stars have been continuously observed. It appeared that five stars show evidence of…
The bulk of available stellar activity observations is frequently checked for the manifestation of signs in comparison with the known characteristic of solar magnetic modulation. The problem is that stellar activity records are usually an…
The application of the Wavelet analysis and Fourier analysis to the dataset of variations of radiation fluxes of solar-like stars and the Sun is examined. In case of the Sun the wavelet-analysis helped us to see a set of values of periods…
The scaling relations for solar-like oscillations provide a translation of the features of the stochastic low-degree modes of oscillation in the Sun to predict the features of solar-like oscillations in other stars with convective outer…
Heartbeat stars are eccentric binary stars in short period orbits whose light curves are shaped by tidal distortion, reflection, and Doppler beaming. Some heartbeat stars exhibit tidally excited oscillations and present new opportunities…
Three-dimensional (3D) hydrodynamic simulations of shell oxygen burning (Meakin and Arnett, 2007b) exhibit bursty, recurrent fluctuations in turbulent kinetic energy. These are shown to be due to a general instability of the convective…
Quasi-periodic oscillations have been seen in the light curves following several magnetar giant flares. These oscillations are of great interest as they probably provide our first ever view of the normal modes of oscillation of neutron…
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…
The observations of the photometric space telescopes CoRoT and Kepler show numerous Blazhko RR Lyrae stars which have non-repetitive modulation cycles. The phenomenon can be explained by multi-periodic, stochastic or chaotic processes. From…