Results 51 to 60 of about 42,668 (331)

Can Extra Mixing in RGB and AGB Stars Be Attributed to Magnetic Mechanisms? [PDF]

, 2007
It is known that there must be some weak form of transport (called cool bottom processing, or CBP) acting in low mass RGB and AGB stars, adding nuclei, newly produced near the hydrogen-burning shell, to the convective envelope.
Andrea Calandra, Charbonnel C., Denissenkov P. A., Denissenkov P. A., Eddington A. S., Fan Y., Gerald J. Wasserburg, Hunsch M., Kenneth M. Nollett, Maurizio Busso, Miesch M. S., Moreno-Insertis F., Rempel M., Schussler M., Spruit H. C., Spruit H. C., Spruit H. C., Spruit H. C., Sweet P. A., Tayler R. J., von Zeipel H., Zahn J.-P.   +21 more
core   +2 more sources

Turbulent Convection in Stellar Interiors. II. The Velocity Field

, 2008
We analyze stellar convection with the aid of 3D hydrodynamic simulations, introducing the turbulent cascade into our theoretical analysis. We devise closures of the Reynolds-decomposed mean field equations by simple physical modeling of the simulations (
Arnett, Asida, Balbus, Batchelor, Bethe, Biermann, Boris, Brandenburg, Browning, Browning, Böhm-Vitense, Böhm-Vitense, Campbell, Casey Meakin, Chandrasekhar, Chandrasekhar, Charbonnel, Clayton, Cvitanović, David Arnett, Dutton, Frisch, Gill, Gleick, Hansen, Heger, Howe, Kippenhahn, Kolmogorov, Kritsuk, Landau, Ludwig, Meakin, Meakin, Meakin, Meynet, Nordlund, Oran, Patrick A. Young, Porter, Porter, Shannon, Stone, Sytine, Tassoul, Tennekes, Thompson, Timmes, Trampedach, Tritton, Turner, Vitense, Woodward, Woodward, Young, Zel'dovich   +55 more
core   +1 more source

On the Detectability of Large-Scale Flows by Asteroseismology

Frontiers in Astronomy and Space Sciences, 2020
Large-scale convective motions are an integral part of stellar interior dynamics and might play a relevant role in stellar dynamo processes. However, they are difficult to detect or characterize.
Markus Roth, Wiebke Herzberg
doaj   +1 more source

Differential Rotation in Stellar Convection Zones

The Astrophysical Journal, 1970
The analysis of an earlier paper (Busse l970a) in which the differential rotation of the Sun was explained as the result of large scale convection in the solar convection zone is extended to include the detailed spatial dependence of the meridional circulation as well as of the differential rotation.
openaire   +1 more source

Modelling Time-dependent Convective Penetration in 1D Stellar Evolution

The Astrophysical Journal
One-dimensional stellar evolution calculations produce uncertain predictions for quantities like the age, core mass, core compactness, and nucleosynthetic yields; a key source of uncertainty is the modeling of interfaces between regions that are ...
Cole Johnston, Mathias Michielsen, Evan H. Anders, Mathieu Renzo, Matteo Cantiello, P. Marchant, Jared A. Goldberg, Richard H. D. Townsend, Gautham Sabhahit, Adam S. Jermyn   +9 more
doaj   +1 more source

The Effect of Convection in Nonlinear One-Zone Stellar Models [PDF]

International Astronomical Union Colloquium, 1993
AbstractWe study the convective nonlinear one-zone models of the pulsating variable stars. In the small convective case, the solution shows chaotic behavior through the period doubling bifurcation as the temperature is lower although the temperature at which the chaos appears is lower than in the case of no convection.
openaire   +1 more source

Diamagnetic pumping near the base of a stellar convection zone [PDF]

Astronomische Nachrichten, 2008
AbstractThe property of inhomogeneous turbulence in conducting fluids to expel large‐scale magnetic fields in the direction of decreasing turbulence intensity is shown as important for the magnetic field dynamics near the base of a stellar convection zone.
Kitchatinov, L. L., Rüdiger, G.
openaire   +2 more sources

Active Carbon and Oxygen Shell Burning Hydrodynamics

, 2006
We have simulated 2.5$\times10^3$ s of the late evolution of a $23 \rm M_\odot$ star with full hydrodynamic behavior. We present the first simulations of a multiple-shell burning epoch, including the concurrent evolution and interaction of an oxygen and ...
Casey A. Meakin, David Arnett, Langer N., Spruit H. C., Stevenson D. J.   +4 more
core   +1 more source

Rossby and Magnetic Prandtl Number Scaling of Stellar Dynamos [PDF]

Astrophysical Journal, 2019
Rotational scaling relationships are examined for the degree of equipartition between magnetic and kinetic energies in stellar convection zones. These scaling relationships are approached from two paradigms, with first a glance at scaling relationship ...
K. Augustson, A. Brun, J. Toomre
semanticscholar   +1 more source

Laser Metal Powder Deposition of Titanium Microalloyed HSLA Steel FeC0.12Si0.25Mn1.3

Advanced Engineering Materials, EarlyView.
This study investigates the additive manufacturing of titanium‐doped high‐strength low‐alloy (HSLA) steel via laser metal deposition. It reveals distinct process‐structure relationships for elemental powder blends compared to prealloyed feedstocks.
Olaf Stelling, Matthias Steinbacher, Nils Ellendt   +2 more
wiley   +1 more source