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We present results from an investigation of the dynamical behavior of buoyant magnetic flux rings in the radiative interior of a uniformly rotating early-type star. Our physical model describes a thin, axisymmetric, toroidal flux tube that…

Astrophysics · Physics 2009-11-07 K. B. MacGregor , J. P. Cassinelli

The first results of numerical analysis of classical r-modes of {\it rapidly} rotating compressible stellar models are reported. The full set of linear perturbation equations of rotating stars in Newtonian gravity are numerically solved…

Astrophysics · Physics 2009-10-31 Shin'ichirou Yoshida , Shigeyuki Karino , Shijun Yoshida , Yoshiharu Eriguchi

In a previous paper we investigated the energy transfer of massive stars to the interstellar medium as a function of time and the geometrical configuration of three massive stars via 3D-mesh-refining hydrodynamics simulations, following the…

Astrophysics of Galaxies · Physics 2014-07-02 Martin Krause , Roland Diehl , Hans Böhringer , Michael Freyberg , Daniel Lubos

We study tidal dissipation in models of rotating giant planets with masses in the range $0.1 - 10 M_\mathrm{J}$ throughout their evolution. Our models incorporate a frequency-dependent turbulent effective viscosity acting on equilibrium…

Earth and Planetary Astrophysics · Physics 2023-11-28 Yaroslav A. Lazovik , Adrian J. Barker , Nils B. de Vries , Aurélie Astoul

Radial velocity observations of K giants have revealed periodic variations for some of the stars. The periods range from approximately 180 to 1000 or more days with velocity amplitudes ranging from approximately 50 m/s to 500 m/s. Except…

Astrophysics · Physics 2007-05-23 Saskia Hekker , Sabine Reffert , Andreas Quirrenbach

Thermal-diffusional pulsation behaviors in planar as well as outwardly and inwardly propagating white dwarf carbon flames are systematically studied. In the 1D numerical simulation, the asymptotic degenerate equation of state and simplified…

High Energy Astrophysical Phenomena · Physics 2017-05-31 Guangzheng Xing , Yibo Zhao , Mikhail Modestov , Cheng Zhou , Yang Gao , Chung K. Law

Observations of clusters and groups imply that such halos are roughly in global thermal equilibrium, with heating balancing cooling when averaged over sufficiently long time- and length-scales; the ICM is, however, very likely to be locally…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Prateek Sharma , Michael McCourt , Eliot Quataert , Ian J. Parrish

Over two dozen early F-type variable stars have been identified which constitute a new class of pulsating stars. These stars typically have periods between 0.5 and 3 days with V-band variability of several hundredths of a magnitude. Given…

Astrophysics · Physics 2008-02-03 K. Krisciunas

Using high-cadence observations from the Zwicky Transient Facility at low Galactic latitudes, we have discovered a new class of pulsating, hot, compact stars. We have found four candidates, exhibiting blue colors ($g-r\leq-0.1$ mag),…

High-Reynolds-number turbulence driven by stellar convection in main-sequence stars generates stochastic gravitational radiation. We calculate the wave-strain power spectral density as a function of the zero-age main-sequence mass for an…

Solar and Stellar Astrophysics · Physics 2015-06-22 M. F. Bennett , A. Melatos

The formation of stars from gas drives the evolution of galaxies. Yet, it remains one of the hardest processes to understand when trying to connect observations of stellar and galaxy populations to models of large scale structure formation.…

Astrophysics of Galaxies · Physics 2015-06-11 Mordecai-Mark Mac Low

After their initial formation, disk galaxies are observed to be rotationally stable over periods of >6 Gyr, implying that any large velocity disturbances of stars and gas clouds are damped rapidly on the timescale of their rotation.…

Astrophysics of Galaxies · Physics 2022-11-08 John Herbert Marr

Hot Jupiters, due to the proximity to their parent stars, are subjected to a strong irradiating flux which governs their radiative and dynamical properties. We compute a suite of 3D circulation models with dual-band radiative transfer,…

Earth and Planetary Astrophysics · Physics 2015-06-03 Rosalba Perna , Kevin Heng , Frederic Pont

Massive rotating single stars with an initial metal composition appropriate for the dwarf galaxy I Zw 18 ([Fe/H]=$-$1.7) are modelled during hydrogen burning for initial masses of 9-300 M$_{\odot}$ and rotational velocities of 0-900 km…

Solar and Stellar Astrophysics · Physics 2015-08-26 D. Szécsi , N. Langer , S. -C. Yoon , D. Sanyal , S. de Mink , C. J. Evans , T. Dermine

We point out that the existence of post-inflationary phases stiffer than radiation leads to the production of stochastic gravitational waves (GW) backgrounds whose logarithmic energy spectra (in critical units) are typically "blue" at high…

High Energy Physics - Phenomenology · Physics 2009-10-31 Massimo Giovannini

Hydrodynamic models of short--period Cepheids were computed to determine the pulsation period as a function of evolutionary time during the first and third crossings of the instability strip. The equations of radiation hydrodynamics and…

Solar and Stellar Astrophysics · Physics 2015-03-24 Yu. A. Fadeyev

Hot Jupiters receive strong stellar irradiation, producing equilibrium temperatures of $1000 - 2500 \ \mathrm{Kelvin}$. Incoming irradiation directly heats just their thin outer layer, down to pressures of $\sim 0.1 \ \mathrm{bars}$. In…

Earth and Planetary Astrophysics · Physics 2020-05-05 Thaddeus D. Komacek , Andrew N. Youdin

Fast yellow pulsating supergiants (FYPS) are a recently-discovered class of evolved massive pulsator. As candidate post-red supergiant objects, and one of the few classes of pulsating evolved massive stars, these objects have incredible…

Our ability to predict the structure and evolution of stars is in part limited by complex, 3D hydrodynamic processes such as convective boundary mixing. Hydrodynamic simulations help us understand the dynamics of stellar convection and…

The Blue Large-Amplitude Pulsators (BLAPs) constitute a new class of pulsating stars. They are hot stars with effective temperatures of ~30 000 K and surface gravities of log g ~ 4.9, that pulsate with periods in the range 20-40 min. Until…

Solar and Stellar Astrophysics · Physics 2018-04-11 Alejandra D. Romero , A. H. Córsico , L. G. Althaus , I. Pelisoli , S. O. Kepler