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Related papers: Topological modes in stellar oscillations

200 papers

Asteroseismology, the study of stellar vibration, has met with great success, shedding light on stellar interior structure, rotation, and magnetism. Prominently known as $\delta$ Scutis, intermediate-mass main-sequence oscillators that…

Solar and Stellar Astrophysics · Physics 2024-10-01 Subrata Kumar Panda , Shravan Hanasoge , Siddharth Dhanpal , Vageesh D. C

Normal-mode oscillation frequencies computed from stellar models differ from those which would be measured from stars with identical interior structures, because of modelling errors in the near-surface layers. These frequency differences…

Solar and Stellar Astrophysics · Physics 2021-10-20 J. M. Joel Ong , Sarbani Basu , Ian W. Roxburgh

Localized states universally appear when a periodic potential is perturbed by defects or terminated at its surface. In this Letter, we theoretically and experimentally demonstrate a mechanism that generates localized states through…

Mesoscale and Nanoscale Physics · Physics 2020-02-25 Yosuke Nakata , Yoshitaka Ito , Yasunobu Nakamura , Ryuichi Shindou

We have identified an important source of mixing in stellar radiation zones, that would arise whenever two conditions are satisfied: (1) the presence of an inverse vertical compositional gradient, and (2) the presence of…

Solar and Stellar Astrophysics · Physics 2015-06-22 Michael Medrano , Pascale Garaud , Stephan Stellmach

Quasi-toroidal oscillations in slowly rotating stars are examined in the framework of general relativity. The oscillation frequency to first order of the rotation rate is not a single value even for uniform rotation unlike the Newtonian…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Yasufumi Kojima

If the Universe has non-trivial spatial topology, observables depend on both the parameters of the spatial manifold and the position and orientation of the observer. In infinite Euclidean space, most cosmological observables arise from the…

Acoustic quadrupole modes of sunlike stars vibrate when perturbed by a passing gravitational wave generated somewhere in the Universe. Here, we compute the imprint of the gravitational waves on the acoustic spectrum of these stars for…

Solar and Stellar Astrophysics · Physics 2017-07-04 Ilídio Lopes

This paper describes some interesting properties of waves in, and oscillations of, the interstellar medium in the direction normal to the plane of the Galaxy. Our purpose is to examine possible reasons for four observed phenomena: the…

Astrophysics · Physics 2009-10-31 Michael A. Walters , Donald P. cox

Asteroseismology is the study of the interior physics and structure of stars using their pulsations. It is applicable to stars across the Hertzsprung-Russell (HR) diagram and a powerful technique to measure masses, radii and ages, but also…

Solar and Stellar Astrophysics · Physics 2026-05-18 Dominic M. Bowman , Lisa Bugnet

Seismology allows for direct observational constraints on the interior structures of stars and planets. Recent observations of Saturn's ring system have revealed the presence of density waves within the rings excited by oscillation modes…

Earth and Planetary Astrophysics · Physics 2015-04-30 Jim Fuller

We derive expressions and develop a numerical technique for the analysis of the line profile moment variations for stars pulsating in oblique non-radial modes. This represents an extension of the widely used spectroscopic moment mode…

Astrophysics · Physics 2009-11-10 O. Kochukhov

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

Stars in close binaries are tidally distorted, and this has a strong effect on their pulsation modes. We compute the mode frequencies and geometries of tidally distorted stars using perturbation theory, accounting for the effects of the…

Solar and Stellar Astrophysics · Physics 2024-11-18 Jim Fuller , Saul Rappaport , Rahul Jayaraman , Don Kurtz , Gerald Handler

Topological defects, such as domain walls and vortices, have long fascinated physicists. A novel twist is added in quantum systems like the B-phase of superfluid helium He$_3$, where vortices are associated with low energy excitations in…

Mesoscale and Nanoscale Physics · Physics 2009-04-02 Ying Ran , Yi Zhang , Ashvin Vishwanath

Knowledge of the geometry of pulsational modes is a prerequisite for seismic modelling of stars. In the case of slowly pulsating B-type (SPB) pulsators, the simple zero-rotation approach so far used for mode identification is usually not…

Solar and Stellar Astrophysics · Physics 2015-06-24 W. Szewczuk , J. Daszyńska-Daszkiewicz

A new method is presented here for evaluating approximately the pulsation modes of relativistic stellar models. This approximation relies on the fact that gravitational radiation influences these modes only on timescales that are much…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Lee Lindblom , Gregory Mendell , James R. Ipser

If the Universe has non-trivial spatial topology, observables depend on both the parameters of the spatial manifold and the position and orientation of the observer. In infinite Euclidean space, most cosmological observables arise from the…

Spatially localized oscillations in periodically forced systems are intriguing phenomena. They may occur in spatially homogeneous media (oscillons), but quite often emerge in heterogeneous media, such as the auditory system, where localized…

Pattern Formation and Solitons · Physics 2020-04-21 Yuval Edri , Ehud Meron , Arik Yochelis

We use time-evolutions of the linear perturbation equations to study the oscillations of rapidly rotating neutrons stars. Our models account for the buoyancy due to composition gradients and we study, for the first time, the nature of the…

Astrophysics · Physics 2009-11-13 A. Passamonti , B. Haskell , N. Andersson , D. I. Jones , I. Hawke

We investigate the nature of low T/W dynamical instabilities in differentially rotating stars by means of linear perturbation. Here, T and W represent rotational kinetic energy and the gravitational binding energy of the star. This is the…

Solar and Stellar Astrophysics · Physics 2016-10-25 Motoyuki Saijo , Shin'ichirou Yoshida