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Related papers: Embedded Oscillating Starless Cores

200 papers

In solar-like stars, acoustic modes provide the main way of probing their internal structure and dynamics. Although these modes are expected to be ubiquitous in stars with convective envelopes, Kepler observations reveal that a significant…

Solar and Stellar Astrophysics · Physics 2026-04-30 Arthur Le Saux , Leïla Bessila , Stéphane Mathis

The effect of temperature inhomogeneity on the periods, their ratios (fundamental vs. first overtone), and the damping times of the standing slow modes in gravitationally stratified solar coronal loops are studied. The effects of optically…

Solar and Stellar Astrophysics · Physics 2015-06-05 A. Abedini , H. Safari , S. Nasiri

Following an approach initially outlined by McKee & Holliman, we investigate the structure and stability of dense, starless molecular cloud cores. We model those as spherical clouds in hydrostatic equilibrium and supported against gravity…

Astrophysics · Physics 2007-05-23 J. Kauffmann , F. Bertoldi

The chemical evolution of the Galaxy is largely guided by the yields from massive stars. Their evolution is heavily influenced by their internal mixing, allowing the stars to live longer and yield a more massive helium core at the end of…

Solar and Stellar Astrophysics · Physics 2022-05-18 May G. Pedersen

Observations of dark cloud cores have been carried out in the mid-infrared using ISOCAM and in the far-infrared using ISOPHOT, both aboard the Infrared Space Observatory. The cores are in most cases detected in emission at 200 and 170…

Astrophysics · Physics 2007-05-23 Aurore Bacmann , Philippe Andre , Derek Ward-Thompson

We present the results of a comprehensive infrared, submillimetre, and millimetre continuum emission study of isolated low-mass star-forming cores in 32 Bok globules, with the aim to investigate the process of star formation in these…

Astrophysics of Galaxies · Physics 2015-05-18 R. Launhardt , D. Nutter , D. Ward-Thompson , T. L. Bourke , Th. Henning , T. Khanzadyan , M. Schmalzl , S. Wolf , R. Zylka

We used near-infrared 2MASS data to construct visual extinction maps of a sample of Southern Bok globules utilizing the NICE method. We derived radial extinction profiles of dense cores identified in the globules and analyzed their…

Astrophysics · Physics 2009-09-28 Germán A. Racca , José W. S. Vilas-Boas , Ramiro de la Reza

In addition to its global North-South anisotropy(1), there are two other enigmatic seismological observations related to the Earth's inner core: asymmetry between its eastern and western hemispheres(2-6) and the presence of a layer of…

Geophysics · Physics 2012-01-06 Thierry Alboussiere , Renaud Deguen , Mickael Melzani

We present an investigation on effect of the ion-neutral (or ambipolar) diffusion heating rate on thermal phases of a molecular cloud. We use the modeling of ambipolar diffusion with two-fluid smoothed particle hydrodynamics, as discussed…

Astrophysics · Physics 2008-04-29 M. Nejad-Asghar , D. Molteni

Constraining the temperature and density structure of dense molecular cloud cores is fundamental for understanding the initial conditions of star formation. We use Herschel observations of the thermal FIR dust emission from nearby isolated…

Non-linear behavior in interstellar chemical models has been recognized for 25 years now. Different mechanisms account for the possibility of multiple fixed-points at steady state, characterized by the ionization degree of the gas. Chemical…

Astrophysics of Galaxies · Physics 2020-11-11 Evelyne Roueff , Jacques Le Bourlot

AIMS: To study the structure of nearby (< 500 pc) dense starless and star-forming cores with the particular goal to identify and understand evolutionary trends in core properties, and to explore the nature of Very Low Luminosity Objects (<…

Astrophysics · Physics 2009-11-13 Jens Kauffmann , Frank Bertoldi , Tyler L. Bourke , Neal J. Evans , Chang Won Lee

Oscillations are abundant in the solar corona. Coronal loop oscillations are typically studied using highly idealised models of magnetic flux tubes. In order to improve our understanding of coronal oscillations, it is necessary to consider…

Solar and Stellar Astrophysics · Physics 2023-08-02 P. Kohutova , P. Antolin , M. Szydlarski , M. Carlsson

The improvements of the knowledge of the seismic structure of the inner core and the complexities thereby revealed ask for a dynamical origin. Sub-solidus convection was one of the early suggestions to explain the seismic anisotropy, but it…

Geophysics · Physics 2014-08-12 Stéphane Labrosse

Aims. We investigate the stability of non-isothermal Bonnor-Ebert spheres with a model that includes a self-consistent calculation of the gas temperature. This way we can discard the assumption of equality between the dust and gas…

Astrophysics of Galaxies · Physics 2015-10-14 O. Sipilä , J. Harju , M. Juvela

Spherical stellar systems such as King models, in which the distribution function is a decreasing function of energy and depends on no other invariant, are stable in the sense of collisionless dynamics. But Weinberg showed, by a clever…

Astrophysics of Galaxies · Physics 2021-03-03 Douglas C. Heggie , Philip G. Breen , Anna Lisa Varri

Aims: We aim to simulate radial profiles of molecular abundances and the gas temperature in cold and heavily shielded starless cores by combining chemical and radiative transfer models. Methods: A determination of the dust temperature in a…

Astrophysics of Galaxies · Physics 2015-06-05 O. Sipilä

We propose an analytical model for the quasistatic evolution of starless cores confined by a constant external pressure, assuming that cores are isothermal and obey a spherically-symmetric density distribution. We model core evolution for…

Astrophysics of Galaxies · Physics 2016-04-20 Kate Pattle

We show that hard encounters in the central regions of globular clusters embedded in dark matter (DM) haloes necessarily lead to the formation of gravitationally-bound stellar envelopes that extend far beyond the nominal tidal radius of the…

Context: The observations of rapidly rotating stars are increasingly detailed and precise thanks to interferometry and asteroseismology; two-dimensional models taking into account the hydrodynamics of these stars are very much needed. Aims:…

Astrophysics · Physics 2009-11-11 Michel Rieutord