English
Related papers

Related papers: The Observational Signatures of Convectively Excit…

200 papers

Gravity modes (g modes), mixed gravito-acoustic modes (mixed modes), and gravito-inertial modes (gi modes) possess unmatched properties as probes for stars with radiative interiors. The structural and dynamical constraints that they are…

There are no strong constraints placed thus far on the amplitude of internal gravity waves (IGWs) that are stochastically excited in the radiative interiors of solar-type stars. Late F-type stars have relatively thin convective envelopes…

Solar and Stellar Astrophysics · Physics 2022-11-09 Sylvain N. Breton , Allan Sacha Brun , Rafael A. García

We discuss low-frequency g modes excited by resonant couplings with weakly unstable oscillatory convective modes in the rotating convective core in early-type main-sequence stars. Our non-adiabatic pulsation analyses including the effect of…

Solar and Stellar Astrophysics · Physics 2020-08-12 Umin Lee , Hideyuki Saio

In main sequence stars the periods of high-order gravity modes are sensitive probes of stellar cores and, in particular, of the chemical composition gradient that develops near the outer edge of the convective core. We present an analytical…

Astrophysics · Physics 2009-11-13 A. Miglio , J. Montalban , A. Noels , P. Eggenberger

Detection of solar gravity modes remains a major challenge to our understanding of the innerparts of the Sun. Their frequencies would enable the derivation of constraints on the core physical properties while their amplitudes can put severe…

Astrophysics · Physics 2009-11-13 K. Belkacem , R. Samadi , M. J. Goupil , M. A. Dupret , A. S. Brun , F. Baudin

The evolution of stars born with a convective core is highly dependent on the efficiency and extent of near core mixing processes, which effectively increases both the core mass and main-sequence lifetime. We investigate to what extent…

Solar and Stellar Astrophysics · Physics 2018-07-04 M. G. Pedersen , C. Aerts , P. I. Pápics , T. M. Rogers

Some physical processes that occur during a star's main-sequence evolution also affect its post main-sequence evolution. It is well known that stars with masses above approximately 1.1 $M_{\odot}$ have well-mixed convective cores on the…

Solar and Stellar Astrophysics · Physics 2024-02-21 Christopher J. Lindsay , J. M. Joel Ong , Sarbani Basu

Bowman et al. (2019) reported low-frequency photometric variability in 164 O- and B-type stars observed with K2 and TESS. They interpret these motions as internal gravity waves, which could be excited stochastically by convection in the…

Thanks to their past history on the main sequence phase, supergiant massive stars develop a convective shell around the helium core. This intermediate convective zone (ICZ) plays an essential role in governing which g-modes are excited.…

Solar and Stellar Astrophysics · Physics 2015-05-13 M. Godart , A. Noels , M. -A. Dupret

The last decade has seen a rapid development in asteroseismology thanks to the CoRoT and Kepler missions. With more detailed asteroseismic observations available, it is becoming possible to infer exactly how oscillations are driven and…

Solar and Stellar Astrophysics · Physics 2020-06-03 Yixiao Zhou , Martin Asplund , Remo Collet , Meridith Joyce

We present estimates of the amplitudes of intrinsically stable stochastically excited radial oscillations in stars near the main sequence. The amplitudes are determined by the balance between acoustical energy generation by turbulent…

Astrophysics · Physics 2007-05-23 G. Houdek , N. J. Balmforth , J. Christensen-Dalsgaard , D. O. Gough

p-mode oscillations in solar-like stars are excited by the outer convection zone in these stars and reflected close to the surface. The p-modes are trapped inside an acoustic cavity, but the modes only stay trapped up to a given frequency…

Astrophysics · Physics 2009-11-13 C. Karoff

Massive stars die in catastrophic explosions, which seed the interstellar medium with heavy elements and produce neutron stars and black holes. Predictions of the explosion's character and the remnant mass depend on models of the star's…

This work concerns the study of the properties of convective cores in main-sequence models of solar-like pulsators and what information they may hold about stellar ages. We verified that the maximum absolute frequency derivative of…

Solar and Stellar Astrophysics · Physics 2014-01-10 I. M. Brandão , M. S. Cunha , J Christensen-Dalsgaard

The envelopes of stars near the Eddington limit are prone to various instabilities. A high Eddington factor in connection with the Fe opacity peak leads to convective instability, and a corresponding envelope inflation may induce…

The excitation of gravity waves by penetrative convective plumes is investigated using 2D direct simulations of compressible convection. The oscillation field is measured by a new technique based on the projection of our simulation data…

Astrophysics · Physics 2007-05-23 Boris Dintrans , Axel Brandenburg , Ake Nordlund , R. F. Stein

Gravito-inertial waves are excited at the interface of convective and radiative regions and by the Reynolds stresses in the bulk of the convection zones of rotating stars and planets. Such waves have notable asteroseismic signatures in the…

Solar and Stellar Astrophysics · Physics 2020-11-18 K. C. Augustson , S. Mathis , A. Astoul

Recent photometric observations of massive stars have identified a low-frequency power excess which appears as stochastic low-frequency variability in light curve observations. We present the oscillation properties of high resolution…

Solar and Stellar Astrophysics · Physics 2024-05-01 William Thompson , Falk Herwig , Paul R. Woodward , Huaqing Mao , Pavel Denissenkov , Dominic M. Bowman , Simon Blouin

Context. Main sequence stars with a convective core are predicted to stochastically excite Internal Gravity Waves (IGWs), which effectively transport angular momentum throughout the stellar interior and explain the observed near-uniform…

The excitation of internal gravity waves by penetrative convective plumes is investigated using 2-D direct simulations of compressible convection. The wave generation is quantitatively studied from the linear response of the radiative zone…

Astrophysics · Physics 2007-05-23 B. Dintrans , A. Brandenburg , A. Nordlund , R. F. Stein
‹ Prev 1 2 3 10 Next ›