English
Related papers

Related papers: Polytropic models of filamentary interstellar clou…

200 papers

Tropical convective clouds evolve over a wide range of temporal and spatial scales, and this makes them difficult to simulate numerically. Here, we propose that their statistical properties can be derived within a simplified…

Atmospheric and Oceanic Physics · Physics 2019-01-09 Timothy J. Garrett , Ian B. Glenn , Steven K. Krueger

(abridged) Within the Orion A molecular cloud, the integral-shaped filament (ISF) is a prominent, degree-long structure of dense gas and dust, with clear signs of recent and on-going high-mass star formation. We used the ArTeMiS bolometer…

In this third and final paper of a series, elastic properties of numerically simulated isotropic packings of spherical beads assembled by different procedures and subjected to a varying confining pressure P are investigated. In addition P,…

Disordered Systems and Neural Networks · Physics 2016-09-08 Ivana Agnolin , Jean-Noël Roux

We leverage recent numerical simulations of highly resolved star-forming regions in a Milky Way-like Galaxy to explore the nature of extended gaseous envelopes around molecular clouds. We extract a sample of two dozen star-forming clouds…

Astrophysics of Galaxies · Physics 2024-03-06 Elijah Mullens , Catherine Zucker , Claire E. Murray , Rowan Smith

Stars form in dense, dusty structures, which are embedded in larger clumps of molecular clouds often showing a clear filamentary structure on large scales (> 1pc). One of the best-studied regions in the Hi-GAL survey can be observed toward…

Astrophysics of Galaxies · Physics 2016-08-19 L. Olmi , M. Cunningham , D. Elia , P. Jones

Ionized gas probes the influence of massive stars on their environment. The Cygnus X region (d~1.5 kpc) is one of the most massive star forming complexes in our Galaxy, in which the Cyg OB2 association (age of 3-5 Myr and stellar mass $2…

We complete previous investigations on the thermodynamics of self-gravitating systems by studying the grand canonical, grand microcanonical and isobaric ensembles. We also discuss the stability of polytropic spheres in the light of a…

Astrophysics · Physics 2009-11-07 P. H. Chavanis

The properties of dust in the interstellar medium (ISM) nearest the Sun are poorly understood because the low column densities of dust toward nearby stars induce little photometric reddening, rendering the grains largely undetectable.…

Filamentary structures are ubiquitous from large-scale molecular clouds (few parsecs) to small-scale circumstellar envelopes around Class 0 sources (~1000 AU to ~0.1 pc). In particular, recent observations with the Herschel Space…

Astrophysics of Galaxies · Physics 2015-06-12 Katherine Lee , Leslie Looney , Doug Johnstone , John Tobin

Observations have suggested substantial departures from pressure equilibrium in the interstellar medium (ISM) in the plane of the Galaxy, even on scales under 50 pc. Nevertheless, multi-phase models of the ISM assume at least locally…

Astrophysics · Physics 2009-11-10 Mordecai-Mark Mac Low , Dinshaw S. Balsara , Jongsoo Kim , Miguel A. Avillez

Recent millimeter/sub-millimeter facilities have revealed the physical properties of filamentary molecular clouds in relation to high-mass star formation. A uniform survey of the nearest, face-on star-forming galaxy, the Large Magellanic…

Context. The interstellar medium is affected by turbulence and observed H i structures in channel maps are shaped by turbulent motions. It is taken for granted by a few theoreticians that observed H i structures do not represent real…

Astrophysics of Galaxies · Physics 2021-01-05 P. M. W. Kalberla , U. Haud

Star-forming galaxies are a highly biased tracer of the underlying dark matter density field. Their clustering can be studied through the cosmic infrared background anisotropies. These anisotropies have been measured from 100 \mum to 2 mm…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Aurélie Pénin , Olivier Doré , Guilaine Lagache , Matthieu Béthermin

A discrete model for the sintering of polydisperse, inhomogeneous arrays of cylinders is presented with empirical contact force-laws, taking into account plastic deformations, cohesion, temperature dependence (melting), and long-time…

Statistical Mechanics · Physics 2007-05-23 Stefan Luding , Karsten Manetsberger , Johannes Müllers

Scintillation spectra of some pulsars have suggested the existence of $\lesssim$ AU scale density structures in the ionized interstellar medium, whose astrophysical correspondence is still a mystery. The detailed study of Brisken et al.…

Astrophysics of Galaxies · Physics 2021-09-28 Xun Shi

We study a new class of equilibrium two-parametric distribution functions of spherical stellar systems with radially anisotropic velocity distribution of stars. The models are less singular counterparts of the so called generalized…

Astrophysics of Galaxies · Physics 2015-06-16 E. V. Polyachenko , V. L. Polyachenko , I. G. Shukhman

Randomly textured polycrystalline materials of constituents with highly anisotropic nature of grains can be considered globally isotropic. In order to determine the isotropic properties, like elasticity or conductivity, we propose a theory…

Materials Science · Physics 2018-12-07 Adam Takacs , Géza Tichy , Péter Dusán Ispánovity

We propose a new statistical model that can reproduce the hierarchical nature of the ubiquitous filamentary structures of molecular clouds. This model is based on the multiplicative random cascade, which is designed to replicate the…

We consider the evolution of an isentropic thermal instability in the atomic zone of a photodissociation region (PDR). In this zone, gas heating and cooling are associated mainly with photoelectric emission from dust grains and…

Astrophysics of Galaxies · Physics 2017-12-13 K. V. Krasnobaev , R. R. Tagirova

The morphological nature of structures that form under gravitational instability has been of central interest to cosmology for over two decades. A remarkable feature of large scale structures in the Universe is that they occupy a relatively…

Astrophysics · Physics 2009-10-28 B. S. Sathyaprakash , V. Sahni , S. F. Shandarin