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Related papers: Dipolar modes in luminous red giants

200 papers

Red giants undergo dramatic and complex structural transformations as they evolve. Angular momentum is transported between the core and envelope during this epoch, a poorly understood process. Here, we infer envelope and core rotation rates…

Solar and Stellar Astrophysics · Physics 2025-06-10 Siddharth Dhanpal , Othman Benomar , Shravan Hanasoge , Jim Fuller

Using data from the NASA spacecraft Kepler, we study solar-like oscillations in red-giant stars in the open cluster NGC6811. We determine oscillation frequencies, frequency separations, period spacings of mixed modes and mode visibilities…

Solar and Stellar Astrophysics · Physics 2017-04-05 T. Arentoft , K. Brogaard , J. Jessen-Hansen , V. Silva Aguirre , H. Kjeldsen , J. R. Mosumgaard , E. L. Sandquist

We report for the first time a parametric fit to the pattern of the \ell = 1 mixed modes in red giants, which is a powerful tool to identify gravity-dominated mixed modes. With these modes, which share the characteristics of pressure and…

Space-borne missions CoRoT and {\it Kepler} are providing a rich harvest of high-quality constraints on solar-like pulsators. Among the seismic parameters, mode damping rates remains poorly understood and thus barely used to infer physical…

Solar and Stellar Astrophysics · Physics 2012-04-03 K. Belkacem , M. A. Dupret , F. Baudin , T. Appourchaux , J. P. Marques , R. Samadi

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…

Solar and Stellar Astrophysics · Physics 2015-10-26 Jim Fuller , Matteo Cantiello , Dennis Stello , Rafael A. Garcia , Lars Bildsten

More than 15000 red giants observed by Kepler for a duration of almost one year became public at the beginning of this year. We analysed a subsample of 416 stars to determine the global properties of acoustic modes (mean large separation…

Solar and Stellar Astrophysics · Physics 2013-08-06 Christina Hedges , Savita Mathur , Michael J. Thompson , Keith B. MacGregor

The unparalleled photometric data obtained by NASA's Kepler Space Telescope has led to improved understanding of red-giant stars and binary stars. We discuss the characterization of known eccentric system, containing a solar-like…

Solar and Stellar Astrophysics · Physics 2015-11-23 P. G. Beck , K. Hambleton , J. Vos , T. Kallinger , R. A. Garcia , S. Mathur , K. Houmani

High-precision space observations, such as made by the \kepler\ and \corot\ missions, allow us to detect mixed modes for $l = 1$ modes in their high signal-to-noise photometry data. By means of asteroseismology, the inner structure of red…

Solar and Stellar Astrophysics · Physics 2014-09-23 C. Jiang , J. Christensen-Dalsgaard

Asteroseismology allows us to probe stellar interiors. Mixed modes can be used to probe the physical conditions in red giant cores. However, we still need to identify the physical mechanisms that transport angular momentum inside red…

Solar and Stellar Astrophysics · Physics 2018-08-08 C. Gehan , B. Mosser , E. Michel , R. Samadi , T. Kallinger

Thanks to the high quality data of space missions, the detection of mixed modes has become possible in numerous stars. In this work, we investigate how the mixing character of dipolar mixed modes changes with stellar evolution, as well as…

Solar and Stellar Astrophysics · Physics 2020-05-12 C. Jiang , M. Cunha , J. Christensen-Dalsgaard , QS. Zhang

The space missions CoRoT and Kepler have provided photometric data of unprecedented quality for asteroseismology. A very rich oscillation pattern has been discovered for red giants, including mixed modes that are used to decipher the red…

Solar and Stellar Astrophysics · Physics 2016-03-23 M. Vrard , B. Mosser , R. Samadi

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…

Astrophysics · Physics 2009-11-13 Shimako Yamada , Atsuo T. Okazaki , Masayuki Y. Fujimoto

Dipole mixed modes observed in the oscillation pattern of red giant stars probe the radiative regions in the stellar core. Oscillation spectra of helium-core-burning stars sometimes show extra peaks that remain unexplained by the dipole…

Solar and Stellar Astrophysics · Physics 2026-01-22 B. Mosser , M. Takata , C. Pinçon , M. S. Cunha , M. Vrard , K. Belkacem , S. Deheuvels , M. Matteuzzi

Context : We still do not know which mechanisms are responsible for the transport of angular momentum inside stars. The recent detection of mixed modes that contain the signature of rotation in the spectra of Kepler subgiants and red giants…

A red giant star is an evolved low- or intermediate-mass star that has exhausted its central hydrogen content, leaving a helium core and a hydrogen-burning shell. Oscillations of stars can be observed as periodic dimmings and brightenings…

Solar and Stellar Astrophysics · Physics 2022-10-26 Gang Li , Sébastien Deheuvels , Jérôme Ballot , François Lignières

The wealth of asteroseismic data for red-giant stars and the precision with which these data have been observed over the last decade calls for investigations to further understand the internal structures of these stars. The aim of this work…

Solar and Stellar Astrophysics · Physics 2018-03-07 S. Hekker , Y. Elsworth , G. C. Angelou

The discovery of the moderate differential rotation between the core and the envelope of evolved solar-like stars could be the signature of a strong magnetic field trapped inside the radiative interior. The population of intermediate-mass…

Solar and Stellar Astrophysics · Physics 2021-06-09 L. Bugnet , V. Prat , S. Mathis , A. Astoul , K. Augustson , R. A. García , S. Mathur , L. Amard , C. Neiner

Asteroseismic investigations based on the wealth of data now available,in particular from the CoRoT and Kepler missions, require a good understanding of the relation between the observed quantities and the properties of the underlying…

Solar and Stellar Astrophysics · Physics 2015-06-23 J. Christensen-Dalsgaard , V. Silva Aguirre , Y. Elsworth , S. Hekker

Sun-like oscillations, that is p-modes excited stochastically by convective noise, have now been observed in a number of Red Giant stars. Compared to those seen in the Sun, these modes are of large amplitude and long period, making the…

Astrophysics · Physics 2008-10-22 N. J. Tarrant , W. J. Chaplin , Y. P. Elsworth , S. A. Spreckley , I. R. Stevens

The space-borne missions CoRoT and Kepler have provided seismic data of unprecedented quality. Among the observed stars, red giants show a complex oscillation pattern exhibiting pressure modes as well as mixed modes. The latter carry…

Solar and Stellar Astrophysics · Physics 2019-11-14 Mathieu Vrard , Margarida S. Cunha