English
Related papers

Related papers: New fitting formula for cosmic non-linear density …

200 papers

We investigate the non-gaussian properties of cosmic-string-seeded linear density perturbations with cold and hot dark matter backgrounds, using high-resolution numerical simulations. We compute the one-point probability density function of…

Astrophysics · Physics 2009-10-30 P. P. Avelino , E. P. S. Shellard , J. H. P. Wu , B. Allen

Our aim in this work is to answer, using simulated narrow-band photometry data, the following general question: What can we learn about galaxies from these new generation cosmological surveys? For instance, can we estimate stellar age and…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-29 William Schoenell , Roberto Cid Fernandes , Narciso Benítez , Natalia Vale Asari

In this paper are discussed possible many body generalizations of the expanding locally anisotropic metric ansatz with respect to approximately Newtonian gravitational systems. This ansatz consistently describes local point-like matter…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-16 P. Castelo Ferreira

Due to gravitational instability, an initially Gaussian density field develops non-Gaussian features as the Universe evolves. The most prominent non-Gaussian features are massive haloes, visible as clusters of galaxies. The distortion of…

Astrophysics · Physics 2015-06-24 Guido Kruse , Peter Schneider

We present a new measurement of the dark and luminous matter distribution of massive elliptical galaxies, and their evolution with redshift, by combining strong lensing and dynamical observables. Our sample of 56 lens galaxies covers a…

A significant number of active galactic nuclei (AGNs) are observed to be hidden behind dust and gas. The distribution of material around AGNs plays an important role in modeling the cosmic X-ray background (CXB), especially the fraction of…

High Energy Astrophysical Phenomena · Physics 2018-02-28 Raj Gohil , David R. Ballantyne

We present detailed calculations of the magnification distribution, including both weak and strong lensing, using very recent solutions of the Dyer-Roeder (1973) equation for light propagation in a inhomogeneous universe with a cosmological…

With the availability of thousands of type Ia supernovae in the near future the magnitude scatter induced by lensing will become a major issue as it affects parameter estimation. Current N-body simulations are too time consuming to be…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-10 Valerio Marra , Miguel Quartin , Luca Amendola

In a mean-field approximation within Kinetic Field Theory, it is possible to derive an accurate analytic expression for the power spectrum of present-day non-linear cosmic density fluctuations. It depends on the theory of gravity and the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-13 Alexander Oestreicher , Harshda Saxena , Niklas Reinhardt , Elena Kozlikin , Johannes Dombrowski , Matthias Bartelmann

We study Newtonian cosmological perturbation theory from a field theoretical point of view. We derive a path integral representation for the cosmological evolution of stochastic fluctuations. Our main result is the closed form of the…

Astrophysics · Physics 2008-12-18 Keisuke Izumi , Jiro Soda

We use the number density of peaks in the smoothed cosmological density field taken from the 2dF Galaxy Redshift Survey to constrain parameters related to the power spectrum of mass fluctuations, n (the spectral index), dn/d(lnk) (rolling…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. De , R. A. C. Croft

A new cosmological test is derived, based on the distribution of individual V/Vmax in a complete redshift-limited sample of distant objects. The fundamental assumption is that, in any bin of absolute luminosity, individual V/Vmax are…

Astrophysics · Physics 2007-05-23 L. Van Waerbeke , G. Mathez , Y. Mellier , H. Bonnet , M. Lachieze-Rey

The probability distribution functions (PDFs) for atomic, molecular, and total gas surface densities of M33 are determined at a resolution of about 50~pc over regions that share coherent morphological properties to unveil fingerprints of…

Astrophysics of Galaxies · Physics 2018-10-03 Edvige Corbelli , Bruce G. Elmegreen , Jonathan Braine , David Thilker

We study filamentary structure in the galaxy distribution at z ~ 0.8 using data from the Deep Extragalactic Evolutionary Probe 2 (DEEP2) Redshift Survey and its evolution to z ~ 0.1 using data from the Sloan Digital Sky Survey (SDSS). We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Ena Choi , Nicholas A. Bond , Michael A. Strauss , Alison L. Coil , Marc Davis , Christopher N. A. Willmer

One way of recovering information about the initial conditions of the Universe is by measuring features of the cosmological density field which are preserved during gravitational evolution and galaxy formation. In this paper we study the…

Astrophysics · Physics 2016-08-30 Rupert A. C. Croft , Enrique Gaztanaga

The mass distribution of halos, as specified by the halo mass function, is a key input for several cosmological probes. The sizes of $N$-body simulations are now such that, for the most part, results need no longer be statistics-limited,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Suman Bhattacharya , Katrin Heitmann , Martin White , Zarija Lukić , Christian Wagner , Salman Habib

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2009-11-06 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

In the present paper we study the radio sources in the NRAO VLA SKY Survey (NVSS) analysing its power spectrum and galaxy distribution. There is a discrepancy between the theoretical models in the literature and the data at large scales. A…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 A. Marcos-Caballero , P. Vielva , E. Martinez-Gonzalez , F. Finelli , A. Gruppuso , F. Schiavon

We consider the shape of the posterior distribution to be used when fitting cosmological models to power spectra measured from galaxy surveys. At very large scales, Gaussian posterior distributions in the power do not approximate the…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-25 Benedict Bahr-Kalus , Will J. Percival , Lado Samushia

An expansion of a density field or particle distribution in basis functions which solve the Poisson equation both provides an easily parallelized n-body force algorithm and simplifies perturbation theories. The expansion converges quickly…

Astrophysics · Physics 2009-10-30 Martin D. Weinberg
‹ Prev 1 4 5 6 7 8 10 Next ›