English
Related papers

Related papers: Molecular clouds have power-law probability distri…

200 papers

The rotational properties of centrally condensed, turbulent molecular cloud cores with velocity fields that are characterized by Gaussian random fields are investigated. It is shown that the observed line width-size relationship can be…

Astrophysics · Physics 2009-10-31 Andreas Burkert , Peter Bodenheimer

The total mass estimate of molecular clouds suffers from the uncertainty in the H$_2$-CO conversion factor, the so-called $X_{\rm CO}$ factor, which is used to convert the $^{12}$CO (1--0) integrated intensity to the H$_2$ column density.…

A simple model accounting for the ejection of heavy particles from the vortical structures of a turbulent flow is introduced. This model involves a space and time discretization of the dynamics and depends on only two parameters: the…

Chaotic Dynamics · Physics 2009-11-13 Jeremie Bec , Raphael Chetrite

We investigate the dynamics of two interacting diffusing particles in an infinite effectively one dimensional system; the particles interact through a step-like potential of width b and height phi_0 and are allowed to pass one another. By…

Biomolecules · Quantitative Biology 2009-11-13 Tobias Ambjornsson , Robert J. Silbey

This paper investigates probability density functions (PDFs) that are continuous everywhere, nearly uniform around the mode of distribution, and adaptable to a variety of distribution shapes ranging from bell-shaped to rectangular. From the…

Machine Learning · Computer Science 2022-04-01 Osamu Fujita

In this paper, we review some of the properties of dense molecular cloud cores. The results presented here rely on three-dimensional numerical simulations of isothermal, magnetized, turbulent, and self-gravitating molecular clouds (MCs) in…

Astrophysics · Physics 2008-08-29 Sami Dib , Roberto Galvan-Madrid , Jongsoo Kim , Enrique Vazquez-Semadeni

The diffusion of colloids inside an active system-e.g. within a living cell or the dynamics of active particles itself (e.g. self-propelled particles) can be modeled through overdamped Langevin equation which contains an additional noise…

Statistical Mechanics · Physics 2024-12-06 Koushik Goswami , K. L. Sebastian

We used CO (2-1) and CO (1-0) data cubes to identify molecular clouds and study their kinematics and dynamics in three nearby galaxies and the inner Milky Way. When observed at similar spatial and velocity resolutions, molecular clouds in…

Astrophysics of Galaxies · Physics 2025-11-03 J. W. Zhou , Sami Dib

One of the targets of the recently launched Fermi Gamma-ray Space Telescope is a diffuse gamma-ray background from dark-matter annihilation or decay in the Galactic halo. N-body simulations and theoretical arguments suggest that the dark…

Astrophysics · Physics 2009-07-22 Samuel K. Lee , Shin'ichiro Ando , Marc Kamionkowski

Recently reported variations in the typical physical properties of Galactic and extra-Galactic molecular clouds (MCs), and in their ability to form stars have been attributed to local variations in the magnitude of interstellar pressure.…

Astrophysics of Galaxies · Physics 2017-01-18 S. Anathpindika , A. Burkert , R. Kuiper

We discuss HD and MHD compressible turbulence as a cloud-forming and cloud-structuring mechanism in the ISM. Results from a numerical model of the turbulent ISM at large scales suggest that the phase-like appearance of the medium, the…

Astrophysics · Physics 2007-05-23 Enrique Vazquez-Semadeni , Thierry Passot

Volume density is a key physical quantity controlling the evolution of the interstellar medium (ISM) and star formation, but it cannot be accessed directly by observations of molecular clouds. We aim at estimating the volume density…

Astrophysics of Galaxies · Physics 2025-05-15 Jan H. Orkisz , Jouni Kainulainen

Molecular clouds, which harbor the birthplaces of stars, form out of the atomic phase of the interstellar medium (ISM). We aim to characterize the atomic and molecular phases of the ISM and set their physical properties into the context of…

At any given scale, 3$\times$2-point statistics extract only three numbers from the joint distribution of the cosmic matter density and galaxy density fluctuations: their variances and their covariance. It is well known that the full shape…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-07 Oliver Friedrich , Lina Castiblanco , Anik Halder , Cora Uhlemann

Quantitatively reliable atomic pair distribution functions (PDFs) have been obtained from nanomaterials in a straightforward way from a standard laboratory transmission electron microscope (TEM). The approach looks very promising for making…

Clouds containing molecular dark matter in quantities relevant for star formation may exist in minihaloes of the type of cold dark matter included in many cosmological simulations or in the regions of some galaxies extending far beyond…

Astrophysics · Physics 2008-11-26 T. A. Bell , T. W. Hartquist , S. Viti , D. A. Williams

Statistical analyses of finite sample distributions usually assume that fluctuations are self-averaging, i.e. that they are statistically similar in different regions of the given sample volume. By using the scale-length method, we test…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Francesco Sylos Labini , Nikolay L. Vasilyev , Yurij V. Baryshev

We find that clouds of optically-thin, pressure-confined gas are prone to fragmentation as they cool below $\sim10^6$ K. This fragmentation follows the lengthscale $\sim{c}_{\text{s}}\,t_{\text{cool}}$, ultimately reaching very small scales…

Astrophysics of Galaxies · Physics 2018-05-10 Michael McCourt , S. Peng Oh , Ryan M. O'Leary , Ann-Marie Madigan

We present a study of the relative orientation between the magnetic field projected onto the plane of sky ($B_{\perp}$) on scales down to 0.4 pc, inferred from the polarized thermal emission of Galactic dust observed by Planck at 353 GHz,…

Astrophysics of Galaxies · Physics 2020-03-04 Juan D. Soler

Despite decades of direct and indirect searches within the Weakly Interacting Massive Particle (WIMP) framework, no conclusive results have been found in the GeV--TeV range. This has motivated exploring alternatives, including new particles…

High Energy Astrophysical Phenomena · Physics 2025-09-23 A. Salces , P. D. L. T. Luque , M. A. Sánchez Conde
‹ Prev 1 8 9 10 Next ›