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Related papers: A closure model with plumes I. The solar convectio…

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Our goal is to improve the theoretical modelling of stochastic excitation of p modes by turbulent convection. With the help of the closure model with plume (CMP) developed in a companion paper, we refine the theoretical description of the…

Astrophysics · Physics 2009-11-11 K. Belkacem , R. Samadi , M. -J. Goupil , F. Kupka , F. Baudin

We perform three-dimensional hydrodynamic simulations of two idealized regimes of stellar convection: a cooling-driven model (Model C) and an entropy-gradient-driven model (Model S). The two regimes exhibit striking contrasts: while Model S…

Solar and Stellar Astrophysics · Physics 2025-11-18 Youhei Masada , Tomoya Takiwaki , Nobumitsu Yoko

The amplitude of solar p-mode oscillations is governed by stochastic excitation and mode damping, both of which take place in the surface convection zone. However, the time-dependent, turbulent nature of convection makes it difficult to…

Solar and Stellar Astrophysics · Physics 2019-07-24 Yixiao Zhou , Martin Asplund , Remo Collet

Global 3D simulations of solar giant-cell convection have provided significant insight into the processes which yield the Sun's observed differential rotation and cyclic dynamo action. However, as we move to higher resolution simulations a…

Solar and Stellar Astrophysics · Physics 2018-06-13 Nicholas J. Nelson , Nicholas A. Featherstone , Mark S. Miesch , Juri Toomre

The first paper of this series established a linear stochastic wave equation for solar-like p-modes, correctly taking the effect of turbulence thereon into account. In this second paper, we aim at deriving simultaneous expressions for the…

Solar and Stellar Astrophysics · Physics 2022-08-31 J. Philidet , K. Belkacem , M. -J. Goupil

We compute the rates P at which acoustic energy is injected into the solar radial p modes for several solar models. The solar models are computed with two different local treatments of convection: the classical mixing-length theory (MLT…

Astrophysics · Physics 2009-11-11 R. Samadi , F. Kupka , M. J. Goupil , Y. Lebreton , C. van't Veer-Menneret

Analyses of a 3D simulation of the upper layers of a solar convective envelope provide constraints on the physical quantities which enter the theoretical formulation of a stochastic excitation model of solar p modes, for instance the…

Astrophysics · Physics 2009-11-07 R. Samadi , A. Nordlund , R. F. Stein , M. J. Goupil , I. Roxburgh

We infer from different seismic observations the energy supplied per unit of time by turbulent convection to the acoustic modes of Alpha Cen A (HD 128620), a star which is similar but not identical to the Sun. The inferred rates of energy…

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

The excitation rate P of solar p-modes is computed with a model of stochatic excitation which involves constraints on the averaged properties of the solar turbulence. These constraints are obtained from a 3D simulation. Resulting values for…

Astrophysics · Physics 2007-05-23 R. Samadi , M. J. Goupil , Y. Lebreton , A. Nordlund , F. Baudin

All numerical simulations of compressible convection reveal the presence of strong downwards directed flows. Thanks to helioseismology, such plumes have now been detected also at the top of the solar convection zone, on super- granular…

Astrophysics · Physics 2015-06-24 Jean-Paul Zahn

Observations suggest that the large-scale convective velocities obtained by solar convection simulations might be over-estimated (convective conundrum). One plausible solution to this could be the small-scale dynamo which cannot be fully…

Solar and Stellar Astrophysics · Physics 2018-05-01 Bidya Binay Karak , Mark Miesch , Yuto Bekki

Determining the behaviour of convection and clouds is one of the biggest challenges in our understanding of exoplanetary climates. Given the lack of in situ observations, one of the most preferable approaches is to use cloud-resolving or…

Earth and Planetary Astrophysics · Physics 2023-06-22 Jun Yang , Yixiao Zhang , Zuntao Fu , Mingyu Yan , Xinyi Song , Mengyu Wei , Jiachen Liu , Feng Ding , Zhihong Tan

Small-scale transient jetlet activity and associated upflows from coronal hole plumes are potential sources of the solar wind. To elucidate the magnetic origins and driving mechanisms of such upflows, we perform three-dimensional radiative…

Solar and Stellar Astrophysics · Physics 2025-11-18 Kamlesh Bora , Lakshmi Pradeep Chitta , Yajie Chen , Damien Przybylski , David Pontin , Nikil Panyam

(abridged) Results from kinematic solar dynamo models employing alpha-effect and turbulent pumping from local convection calculations are presented. We estimate the magnitude of these effects to be around 2-3 m/s. The rotation profile of…

Astrophysics · Physics 2008-11-26 P. J. Käpylä , M. J. Korpi , I. Tuominen

Plumes in a convective flow are considered to be relevant to the turbulent transport in convection. The effective mass, momentum, and heat transports in the convective turbulence are investigated in the framework of time--space double…

Solar and Stellar Astrophysics · Physics 2022-09-21 Nobumitsu Yokoi , Youhei Masada , Tomoya Takiwaki

Context: The paradigm of convection in solar-like stars is questioned based on recent solar observations. Aims: The primary aim is to study the effects of surface-driven entropy rain on convection zone structure and flows. Methods:…

Solar and Stellar Astrophysics · Physics 2025-06-11 P. J. Käpylä

We compute, for several solar models, the rates P at which the solar radial p modes are expected to be excited. The solar models are computed with two different local treatments of convection : the classical mixing-length theory (MLT…

Astrophysics · Physics 2007-05-23 R. Samadi , M. -J. Goupil , Y. Lebreton , C. Van't Veer , F. Kupka

Recent 3D-simulations have shown that the turbulent kinetic flux (TKF) is significant. We discuss the effects of TKF on the size of convection zone and find that the TKF may help to solve the solar abundance problem. The solar abundance…

Solar and Stellar Astrophysics · Physics 2015-06-19 Q. S. Zhang

A 3D simulation of the upper part of the solar convective zone is used to derive constraints about the averaged and dynamic properties of solar turbulent convection. Theses constraints are then used to compute the acoustic energy supply…

Astrophysics · Physics 2007-05-23 R. Samadi , A. Nordlund , R. F. Stein , M. J. Goupil , I. Roxburgh

Fluid-dynamics simulations of global solar convection are a critically important tool for assessing the dynamics of the solar interior. However, simulation studies with a fully compressible hydrodynamics code are not yet common. The…

Solar and Stellar Astrophysics · Physics 2026-01-09 Keiji Hayashi , Alexander G. Kosovichev , Chunlei Liang
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