English
Related papers

Related papers: The Probability Distribution Function of Gas Surfa…

200 papers

We present probability distribution functions (PDFs) of the surface densities of ionized and neutral gas in the nearby spiral galaxies M31 and M51, as well as of dust emission and extinction Av in M31. The PDFs are close to lognormal and…

Astrophysics of Galaxies · Physics 2015-06-23 Elly M. Berkhuijsen , Andrew Fletcher

The probability distribution function (PDF) of the mass surface density of molecular clouds provides essential information about the structure of molecular cloud gas and condensed structures out of which stars may form. In general, the PDF…

Astrophysics of Galaxies · Physics 2015-06-22 Jörg Fischera

The probability distribution function (PDF) of the mass surface density is an essential characteristic of the structure of molecular clouds or the interstellar medium in general. Observations of the PDF of molecular clouds indicate a…

Astrophysics of Galaxies · Physics 2015-06-18 Joerg Fischera

In a search for the signature of turbulence in the diffuse interstellar medium in gas density distributions, we determined the probability distribution functions (PDFs) of the average volume densities of the diffuse gas. The densities were…

Astrophysics · Physics 2009-11-13 E. M. Berkhuijsen , A. Fletcher

The shape of the probability distribution function (PDF) of molecular clouds is an important ingredient for modern theories of star formation and turbulence. Recently, several studies have pointed out observational difficulties with…

Astrophysics of Galaxies · Physics 2015-10-07 Blakesley Burkhart , Min-Young Lee , Claire Murray , Snezana Stanimirovic

Both observational and theoretical research over the past decade has demonstrated that the probability distribution function (PDF) of the gas density in turbulent molecular clouds is a key ingredient for understanding star formation. It has…

Astrophysics of Galaxies · Physics 2018-11-28 Bastian Körtgen , Christoph Federrath , Robi Banerjee

We conduct numerical experiments to determine the density probability distribution function (PDF) produced in supersonic, isothermal, self-gravitating turbulence of the sort that is ubiquitous in star-forming molecular clouds. Our…

Astrophysics of Galaxies · Physics 2021-08-10 Shivan Khullar , Christoph Federrath , Mark R. Krumholz , Christopher D. Matzner

The probability distribution functions (PDFs) of the average densities of the diffuse ionized gas (DIG) and the diffuse atomic gas are close to lognormal, especially when lines of sight at |b|<5 degree and |b|>5 degree are considered…

Astrophysics of Galaxies · Physics 2015-05-27 Elly M. Berkhuijsen , Andrew Fletcher

We characterize the column density probability distributions functions (PDFs) of the atomic hydrogen gas, HI, associated with seven Galactic molecular clouds (MCs). We use 21 cm observations from the Leiden/Argentine/Bonn Galactic HI Survey…

Astrophysics of Galaxies · Physics 2016-10-05 Nia Imara , Blakesley Burkhart

In this Letter we investigate the shape of the probability distribution of column densities (PDF) in molecular clouds. Through the use of low-noise, extinction-calibrated \textit{Herschel}/\textit{Planck} emission data for eight molecular…

Solar and Stellar Astrophysics · Physics 2015-06-23 Marco Lombardi , João Alves , Charles J. Lada

The probability distribution functions (PDF) of density of the ISM in galactic disks and global star formation rate are discussed. Three-dimensional hydrodynamic simulations show that the PDFs in globally stable, inhomogeneous ISM in…

Astrophysics · Physics 2011-02-11 Keiichi Wada , Colin Norman

We analyse the distribution of CO brightness temperature and integrated intensity in M51 at ~40 pc resolution using new CO data from the Plateau de Bure Arcsecond Whirlpool Survey (PAWS). We present probability distribution functions (PDFs)…

We have obtained column density maps for an unbiased sample of 120 molecular clouds in the third quadrant of the Milky Way mid-plane (b$\le |5|^{\circ}$) within the galactic longitude range from 195$^{\circ}$ to 225$^{\circ}$, using the…

Astrophysics of Galaxies · Physics 2022-08-31 Yuehui Ma , Hongchi Wang , Miaomiao Zhang , Chen Wang , Shaobo Zhang , Yao Liu , Chong Li , Yuqing Zheng , Lixia Yuan , Ji Yang

Column density (N) PDFs serve as a powerful tool to characterize the physical processes that influence the structure of molecular clouds. Star-forming clouds can best be characterized by lognormal PDFs for the lower N range and a power-law…

We investigate the form of the one-point probability distribution function (pdf) for the density field of the interstellar medium using numerical simulations that successively reduce the number of physical processes included.…

Astrophysics · Physics 2014-10-13 J. Scalo , E. Vazquez-Semadeni , D. Chappell , T. Passot

The one-point probability distribution function (PDF) of the matter density field in the universe is a fundamental property that plays an essential role in cosmology for estimates such as gravitational weak lensing, non-linear clustering,…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-10 Anatoly Klypin , Francisco Prada , Juan Betancort-Rijo , Franco D. Albareti

The relationship between the star formation rate and surface density of neutral gas within the disk of M33 is examined with new imaging observations of CO J=1-0 emission gathered with the FCRAO 14m telescope and IRAS HiRes images of the 60…

Astrophysics · Physics 2009-11-10 M. H. Heyer , E. Corbelli , S. E. Schneider , J. S. Young

We investigate the behavior of the magnetic pressure, $b^2$, in fully turbulent MHD flows in ``1+2/3'' dimensions by means of its effect on the probability density function (PDF) of the density field. We start by reviewing our previous…

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

Using a suite of self-similar cosmological simulations, we measure the probability distribution functions (PDFs) of real-space density, redshift-space density, and their geometric mean. We find that the real-space density PDF is…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Huanqing Chen , Nickolay Y. Gnedin , Philip Mansfield
‹ Prev 1 2 3 10 Next ›