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Related papers: A method to analyse velocity structure

200 papers

Since molecules are ubiquitous in space, the study of the 'Molecular Universe' could unfold the mystery of the existing Interstellar medium. Star formation is linked to the chemical evolution processes. Thus, an analysis of the formation of…

Astrophysics of Galaxies · Physics 2024-05-29 Bratati Bhat

We introduce a new self-consistent structure finding algorithm that parses large scale cosmological structure into clusters, filaments and voids. This structure finding algorithm probes the cosmological structure at multiple scales and…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-04 Ali Snedden , Lara Arielle Phillips , Grant J. Mathews , Jared Coughlin , In-Saeng Suh , Aparna Bhattacharya

One way of characterizing the topological and structural properties of vertices and edges in a graph is by using structural similarity measures. Measures like Cosine, Jaccard and Dice compute the similarities restricted to the immediate…

Social and Information Networks · Computer Science 2018-05-04 Eduar Castrillo , Elizabeth León , Jonatan Gómez

Accounting for stellar activity is a crucial component of the search for ever-smaller planets orbiting stars of all spectral types. We use Doppler imaging methods to demonstrate that starspot induced radial velocity variability can be…

Solar and Stellar Astrophysics · Physics 2017-01-18 J. R. Barnes , S. V. Jeffers , G. Anglada-Escude , C. A. Haswell , H. R. A. Jones , M. Tuomi , F. Feng , J. S. Jenkins , P. Petit

We consider travel time tomography problems involving detection of high contrast, discrete high velocity structures. This results in a discrete nonlinear inverse problem, for which traditional grid-based models and iterative linearized…

Data Analysis, Statistics and Probability · Physics 2017-07-07 Yenting Lin , Antonio Ortega

Many young star clusters appear to be fractal, i.e. they appear to be concentrated in a nested hierarchy of clusters within clusters. We present a new algorithm for statistically analysing the distribution of stars to quantify the level of…

Astrophysics of Galaxies · Physics 2017-01-20 S. E. Jaffa , A. P. Whitworth , O. Lomax

The interstellar medium is highly structured, presenting a range of morphologies across spatial scales. The large data sets resulting from observational surveys and state-of-the-art simulations studying these hierarchical structures means…

Astrophysics of Galaxies · Physics 2022-08-31 Seamus D. Clarke , Sarah E. Jaffa , Anthony P. Whitworth

In this paper we provide new methodology for inference of the geometric features of a multivariate density in deconvolution. Our approach is based on multiscale tests to detect significant directional derivatives of the unknown density at…

Methodology · Statistics 2016-11-21 Konstantin Eckle , Nicolai Bissantz , Holger Dette

In this article we give an account of a method of smoothing spatial inhomogeneous data sets by using wavelet reconstruction on a regular grid in an auxilliary space onto which the original data is mapped. In a previous paper by the present…

Astrophysics · Physics 2009-10-28 S. Rauzy , M. Lachièze-Rey , R. N. Henriksen

We determine the distribution of stellar surface densities, \Sigma, from models of static and dynamically evolving star clusters with different morphologies, including both radially smooth and substructured clusters. We find that the \Sigma…

Astrophysics of Galaxies · Physics 2015-06-11 Richard J. Parker , Michael R. Meyer

In several environmental applications data are functions of time, essentially con- tinuous, observed and recorded discretely, and spatially correlated. Most of the methods for analyzing such data are extensions of spatial statistical tools…

Methodology · Statistics 2011-06-28 Elvira Romano , Antonio Balzanella , Rosanna Verde

From the tangential velocities of stars all over the sky, one can, in a statistical way, infer their 3D velocity distribution. An application to Hipparcos data reveals rich structure in the planar stellar motions: there are several moving…

Astrophysics · Physics 2007-05-23 Walter Dehnen

In this work, we derive a spatially resolved map of the line-of-sight velocity of the interstellar medium and use it, along with a second map of line-of-sight velocity from Paper I of this series, to determine the nature of gaseous spiral…

Astrophysics of Galaxies · Physics 2018-11-14 Kirill Tchernyshyov , J. E. G. Peek , Gail Zasowski

We study the links between star formation history and structure for a large mass-selected galaxy sample at 0.05 < z_phot < 0.30. The galaxies inhabit a very broad range of environments, from cluster cores to the field. Using HST images, we…

Based on the most complete sample of Galactic open star clusters up to 1.8 kpc, we performed statistical analysis of the distribution of open cluster parameters in order to understand the Galactic structure. The geometrical characteristics…

Astrophysics of Galaxies · Physics 2017-07-31 Yogesh C. Joshi

A new numerical technique to identify the cosmic web is proposed. It is based on locating multi-stream flows, i.e. the places where the velocity field is multi-valued. The method is local in Eulerian space, simple and computaionally…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Sergei F. Shandarin

Accurate measurement of galaxy structures is a prerequisite for quantitative investigation of galaxy properties or evolution. Yet, the impact of galaxy inclination and dust on commonly used metrics of galaxy structure is poorly quantified.…

Astrophysics of Galaxies · Physics 2017-03-23 Brian Devour , Eric Bell

The processes regulating star formation in galaxies are thought to act across a hierarchy of spatial scales. To connect extragalactic star formation relations from global and kpc-scale measurements to recent cloud-scale resolution studies,…

We develop information-theoretic measures of spatial structure and pattern in more than one dimension. As is well known, the entropy density of a two-dimensional configuration can be efficiently and accurately estimated via a converging…

Statistical Mechanics · Physics 2009-11-07 David P. Feldman , James P. Crutchfield

We propose a new strategy to probe the power spectrum on large scales using galaxy peculiar velocities. We explore the properties of surveys that cover only two small fields in opposing directions on the sky. Surveys of this type have…

Astrophysics · Physics 2009-10-30 Hume A. Feldman , Richard Watkins
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