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We present simple analytic approximations for the linear and fully evolved nonlinear mass power spectrum for spatially flat cold dark matter (CDM) cosmological models with quintessence (Q). Quintessence is a time evolving, spatially…

Astrophysics · Physics 2009-10-31 Chung-Pei Ma , R. R. Caldwell , Paul Bode , Limin Wang

Cold dark matter (CDM) is a well established paradigm to describe cosmological structure formation, and works extraordinarily well on large, linear, scales. Progressing further in dark matter physics requires being able to understand…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-20 David J. E. Marsh

We lay out the framework to numerically study nonlinear structure formation in the context of scalar-field-coupled cold dark matter models (phiCDM models) where the scalar field phi serves as dynamical dark energy. Adopting parameters for…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 HongSheng Zhao , Andrea V. Maccio' , Baojiu Li , Henk Hoekstra , Martin Feix

In this proceeding, we present the results of a semi-analytic study of CDM substructure as a function of the primordial power spectrum. We apply our method to several tilted models in the LCDM framework with n=0.85-1.1, sigma_8=0.65-1.2…

Astrophysics · Physics 2009-11-07 Andrew R. Zentner , James S. Bullock

The mass function of cluster-size halos and their redshift distribution are computed for 12 distinct accelerating cosmological scenarios and confronted to the predictions of the conventional flat $\Lambda$CDM model. The comparison with…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-27 S. Basilakos , M. Plionis , J. A. S. Lima

The abundance of dark matter haloes is a key cosmological probe in forthcoming galaxy surveys. The theoretical understanding of the halo mass function (HMF) is limited by our incomplete knowledge of the origin of non-universality and its…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-05 Ningyuan Guo , Luisa Lucie-Smith , Hiranya V. Peiris , Andrew Pontzen , Davide Piras

We study the local response to long wavelength fluctuations in cosmological $N$-body simulations, focusing on the matter and halo power spectra, halo abundance and non-linear transformations of the density field. The long wavelength mode is…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Tobias Baldauf , Uroš Seljak , Leonardo Senatore , Matias Zaldarriaga

We constrain two non-flat time-evolving dark energy cosmological models by using Hubble parameter data, Type Ia supernova apparent magnitude measurements, and baryonic acoustic oscillation peak length scale observations. The inclusion of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Omer Farooq , Data Mania , Bharat Ratra

We use the physically-consistent tilted spatially-flat and untilted non-flat $\Lambda$CDM inflation models to constrain cosmological parameter values with the Planck 2015 cosmic microwave background (CMB) anisotropy data and recent Type Ia…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-19 Chan-Gyung Park , Bharat Ratra

We study the nonlinear growth of structure in nonlocal gravity models with the aid of N-body simulation and the spherical collapse and halo models. We focus on a model in which the inverse-squared of the d'Alembertian operator acts on the…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-25 Alexandre Barreira , Baojiu Li , Wojciech A. Hellwing , Carlton M. Baugh , Silvia Pascoli

We model the nonlinear growth of cosmic structure in different dark energy models, using large volume N-body simulations. We consider a range of quintessence models which feature both rapidly and slowly varying dark energy equations of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 E. Jennings , C. M. Baugh , R. E. Angulo , S. Pascoli

Some beyond $\Lambda$CDM cosmological models have dark-sector energy densities that suffer phase transitions. Fluctuations entering the horizon during such a transition can receive enhancements that ultimately show up as a distinctive bump…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 Dante V. Gomez-Navarro , Alexander Mead , Alejandro Aviles , Axel de la Macorra

We present N-body simulation calculations of the dependence of the power spectrum of non-linear cosmological mass density fluctuations on the equation of state of the dark energy, w=p/rho. At fixed linear theory power, increasing w leads to…

Astrophysics · Physics 2009-11-11 Patrick McDonald , Hy Trac , Carlo Contaldi

In the present investigation we use observational data of $ f \sigma_ {8} $ to determine observational constraints in the plane $(\Omega_{m0},\sigma_{8})$ using two different methods: the growth factor parametrization and the numerical…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 A. M. Velásquez-Toribio , Júlio C. Fabris

We investigate two dark energy cosmological models (i.e., the $\Lambda$CDM and $\phi$CDM models) with massive neutrinos assuming two different neutrino mass hierarchies in both the spatially flat and non-flat scenarios, where in the…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-15 Yun Chen , Bharat Ratra , Marek Biesiada , Song Li , Zong-Hong Zhu

High-resolution N-body simulations are used to examine the power spectrum dependence of the concentration of galaxy-sized dark matter halos. It is found that dark halo concentrations depend on the amplitude of mass fluctuations as well as…

Astrophysics · Physics 2009-07-09 V. R. Eke , J. F. Navarro , M. Steinmetz

In the context of forthcoming galaxy surveys, to ensure unbiased constraints on cosmology and gravity when using non-linear structure information, percent-level accuracy is required when modelling the power spectrum. This calls for…

Cosmic background neutrinos have a large velocity dispersion, which causes the evolution of long-wavelength density perturbations to depend on scale. This scale-dependent growth leads to the well-known suppression in the linear theory…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-27 Chi-Ting Chiang , Wayne Hu , Yin Li , Marilena LoVerde

We present results from a study of bias and its evolution for galaxy-size halos in a large, high-resolution simulation of a LCDM model. We consider the evolution of bias estimated using two-point correlation function (b_xi), power spectrum…

Astrophysics · Physics 2009-10-31 Andrey Kravtsov , Anatoly Klypin

We investigate the matter density perturbation $\delta_m$ and power spectrum $P(k)$ in the running vacuum model (RVM) with the cosmological constant being a function of the Hubble parameter, given by $\Lambda = \Lambda_0 + 6 \sigma H H_0+…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 Chao-Qiang Geng , Chung-Chi Lee