Related papers: Rapidly rotating red giants
We aim to describe the oscillation power excess observed in Kepler red giants, and to investigate empirical scaling relations governing these parameters. From these scalings relations, we derive new physical properties of red giant…
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 has increased, but the quality of these…
The physical structures of the outer atmospheres of red giants are not known. They are certainly complex and a range of recent observations are showing that we need to embrace to non-classical atmosphere models to interpret these regions.…
Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of sub-stellar companions by their hosting stars. In the…
The Kepler mission has provided exquisite data to perform an ensemble asteroseismic analysis on evolved stars. In this work we systematically characterize solar-like oscillations and granulation for 16,094 oscillating red giants, using…
Time-resolved photometry of tens of thousands of red giant stars from space missions like Kepler and K2 has created the need for automated asteroseismic analysis methods. The first and most fundamental step in such analysis, is to identify…
When a star evolves into a red giant, the enhanced coupling between core-based gravity modes and envelope-based pressure modes forms mixed modes, allowing its deep interior to be probed by asteroseismology. The ability to obtain information…
The influence of rotation on the properties of red giants is studied in the context of the asteroseismic modelling of these stars. While red giants exhibit low surface rotational velocities, we find that the rotational history of the star…
Galactic archaeology largely relies on precise ages of distant evolved stars in the Milky Way. Nowadays, asteroseismology can deliver ages for many red giants observed with high-cadence, high-precision photometric space missions. Our aim is…
Asteroseismology is a powerful tool to measure the fundamental properties of stars and probe their interiors. This is particularly efficient for red giants because their modes are well detectable and give information on their deep layers.…
Internal stellar magnetic fields are inaccessible to direct observations and little is known about their amplitude, geometry and evolution. We demonstrate that strong magnetic fields in the cores of red giant stars can be identified with…
Mixed modes seen in evolved stars carry information on their deeper layers that can place stringent constraints on their physics and on their global properties (mass, age, etc...). In this study, we present a method to identify and measure…
The angular momentum (AM) evolution of stellar interiors, along with the resulting rotation rates of stellar remnants, remains poorly understood. Asteroseismic measurements of red giant stars reveal that their cores rotate much faster than…
When low- and intermediate-mass stars evolve off the main sequence, they expand and cool into the red giant stages of evolution, which include those associated with shell H burning (the red giant branch), core He burning (the red clump),…
Context: Recent asteroseismic observations have led to the determination of rotational frequency splittings for l=1 mixed modes in red giants. Aims: We investigate how these observed splittings can constrain the modelling of the physical…
Asteroseismic studies of red giants generally assume that the oscillation modes can be treated as linear perturbations to the background star. However, observations by the Kepler mission show that the oscillation amplitudes increase…
Recent measurements of magnetic field strength inside the radiative interior of red giant stars open the way towards the characterization of the geometry of stable large-scale magnetic fields. However, current measurements do not properly…
We investigate the tidal interactions of a red giant with a main sequence in the dense stellar core of globular clusters by Smoothed Particle Hydrodynamics method. Two models of $0.8 \msun$ red giant with the surface radii 20 and $85…
Long timeseries of data increase the frequency resolution in the power spectrum. This allows for resolving stochastically excited modes with long mode lifetimes, as well as features that are close together in frequency. The CoRoT fields…
The orbital angular momentum of a close-orbiting giant planet can be sufficiently large that, if transferred to the envelope of the host star during the red giant branch (RGB) evolution, it can spin-up the star's rotation to unusually large…