中文
相关论文

相关论文: Constraints on the Cosmic Equation of State using …

200 篇论文

The current expansion of the Universe has been observed to be accelerating, and the widely accepted spatially-flat concordance model of general relativistic cosmology attributes this phenomenon to a constant dark energy, a cosmological…

宇宙学与河外天体物理 · 物理学 2023-04-13 Shulei Cao

Double-source-plane strong gravitational lenses (DSPLs), with two sources at different redshifts, are independent cosmological probes of the dark energy equation of state parameter $w$ and the matter density parameter $\Omega_{\rm m}$. We…

We show that the abundance and redshift distribution ($dN/dz$) of galaxy clusters in future high--yield cluster surveys, combined with the spatial power spectrum ($P_c(k)$) of the same clusters, can place significant constraints on the…

天体物理学 · 物理学 2008-11-26 Sheng Wang , Justin Khoury , Zoltan Haiman , Morgan May

In the standard flat cosmological constant ($\Lambda$) cold dark matter (CDM) cosmology, a model of two populations of lens halos for strong gravitational lensing can reproduce the results of the Jodrell-Bank VLA Astrometric Survey (JVAS)…

天体物理学 · 物理学 2009-11-10 Da-Ming Chen

We detect weak gravitational lensing of the cosmic microwave background (CMB) at the location of the WISExSCOS (WxS) galaxies using the publicly available Planck lensing convergence map. By stacking the lensing convergence map at the…

宇宙学与河外天体物理 · 物理学 2018-08-15 Srinivasan Raghunathan , Federico Bianchini , Christian L. Reichardt

In this paper, we study a model which is composed by the cosmological constant and dark matter with nonzero equation of state parameter, which could be called as $\Lambda$wDM. In the synchronous gauge, we obtain the perturbation equations…

宇宙学与河外天体物理 · 物理学 2015-12-01 Weiqiang Yang , Lixin Xu

We obtain cosmological constraints from a measurement of the spherically averaged power spectrum (PS) of the distribution of about 90000 luminous red galaxies (LRGs) across 7646 deg2 in the Northern Galactic Cap from the DR7 of the SDSS.…

宇宙学与河外天体物理 · 物理学 2012-06-13 Francesco Montesano , Ariel G. Sanchez , Stefanie Phleps

New observational constraints on the cosmic matter density $\Omega_m$ and an effectively redshift-independent equation of state parameter $w_x$ of the dark energy are obtained while simultaneously testing the strong and null energy…

(Abridged) This is the first of a series of papers in which we derive simultaneous constraints on cosmological parameters and X-ray scaling relations using observations of the growth of massive, X-ray flux-selected galaxy clusters. Our data…

宇宙学与河外天体物理 · 物理学 2015-05-14 Adam Mantz , Steven W. Allen , David Rapetti , Harald Ebeling

Reconstructing the expansion history of the Universe from type Ia supernovae data, we fit the growth rate measurements and put model-independent constraints on some key cosmological parameters, namely, $\Omega_\mathrm{m},\gamma$, and…

宇宙学与河外天体物理 · 物理学 2018-05-10 Benjamin L'Huillier , Arman Shafieloo , Hyungjin Kim

I discuss several issues that arise when trying to constrain the dark energy equation of state using correlations of the integrated Sachs-Wolfe effect with galaxy counts and lensing of the cosmic microwave background. These techniques are…

天体物理学 · 物理学 2009-11-10 Benjamin Gold

Future large ensembles of time delay lenses have the potential to provide interesting cosmological constraints complementary to those of other methods. In a flat universe with constant w including a Planck prior, LSST time delay…

宇宙学与河外天体物理 · 物理学 2009-11-13 Dan Coe , Leonidas Moustakas

The nature of dark matter and dark energy are among the central questions in cosmology. Strong gravitational lenses with multiple source planes provide a geometric probe of cosmology: the ratio of deflection angles at different redshifts…

Inferring spatial curvature of the Universe with high-fidelity is a longstanding interest in cosmology. However, the strong degeneracy between dark energy equation-of-state parameter $w$ and curvature density parameter $\Omega_{\rm K}$ has…

宇宙学与河外天体物理 · 物理学 2024-11-11 Yang Hu , Suhail Dhawan

Major observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark energy that cannot be represented solely…

天体物理学 · 物理学 2009-03-12 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…

宇宙学与河外天体物理 · 物理学 2013-09-17 Muhammad Omer Farooq

We present a study of the baryonic fraction in galaxy clusters aimed at constraining the cosmological parameters Omega_m, Omega_Lambda and the ratio between the pressure and density of the ``dark'' energy, w. We use results on the…

天体物理学 · 物理学 2008-11-26 S. Ettori , P. Tozzi , P. Rosati

Ongoing and future wide-field galaxy surveys can be used to locate a number of clusters of galaxies with cosmic shear measurement alone. We study constraints on cosmological models using statistics of weak lensing selected galaxy clusters.…

宇宙学与河外天体物理 · 物理学 2016-02-17 Masato Shirasaki , Takashi Hamana , Naoki Yoshida

We investigate the impact of hierarchical galaxy merging on the statistics of gravitational lensing of distant sources. Since no definite theoretical predictions for the merging history of luminous galaxies exist, we adopt a parametrized…

天体物理学 · 物理学 2019-08-17 Hans-Walter Rix , Dan Maoz , Edwin L. Turner , Masataka Fukugita

We present constraints on the cosmological constant $\lambda_{0}$ from gravitational lensing statistics of the Jodrell Bank-VLA Astrometric Survey (JVAS). Although this is the largest gravitational lens survey which has been analysed,…

天体物理学 · 物理学 2009-10-31 P. Helbig , D. R. Marlow , R. Quast , P. N. Wilkinson , I. W. A. Browne , L. V. E. Koopmans