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Related papers: Surveying the dark side

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The effective redshift distribution $n(z)$ of galaxies is a critical component in the study of weak gravitational lensing. Here, we introduce a new method for determining $n(z)$ for weak lensing surveys based on high-quality redshifts and…

A new method to investigate a possible time-dependence of the dark energy equation of state $w$ is proposed. We apply this methodology to two of the most recent data sets of type Ia supernova (Union2 and SDSS) and the baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 E. M. Barboza , J. S. Alcaniz

Breakthroughs in physics and astrophysics are often driven by technological advances, with the recent detection of gravitational waves being one such example. This white paper focuses upon how improved astrometric and spectroscopic…

We define and characterise a sample of 1.3 million galaxies extracted from the first year of Dark Energy Survey data, optimised to measure Baryon Acoustic Oscillations in the presence of significant redshift uncertainties. The sample is…

In this paper I discuss what we truly know about dark energy. I shall argue that up to date our single indication for the existence of dark energy comes from distance measurements and their relation to redshift. Supernovae, CMB anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-01 Ruth Durrer

Detecting dark energy dynamics is the main quest of current dark energy research. Addressing the issue demands a fully consistent analysis of CMB, large scale structure and SN-Ia data with multi-parameter freedom valid for all redshifts.…

Astrophysics · Physics 2008-11-26 P. S. Corasaniti , M. Kunz , D. Parkinson , E. J. Copeland , B. A. Bassett

The expansion of the universe causes spacetime curvature, distinguishing between distances measured along and transverse to the line of sight. The ratio of these distances, e.g. the cosmic shear distortion of a sphere defined by…

Astrophysics · Physics 2009-11-07 Eric V. Linder

The new 182 gold supernova Ia data, the baryon acoustic oscillation measurement and the shift parameter determined from the Sloan Digital Sky Survey and the three-year Wilkinson Microwave Anisotropy Probe data are combined to reconstruct…

Astrophysics · Physics 2008-11-26 Yungui Gong , Anzhong Wang

This review summarizes recent attempts to reconstruct the expansion history of the Universe and to probe the nature of dark energy. Reconstruction methods can be broadly classified into parametric and non-parametric approaches. It is…

Astrophysics · Physics 2008-11-26 Varun Sahni , Alexei Starobinsky

Understanding of the nature of dark energy, which appears to drive the expansion of the universe, is one of the central problems of physical cosmology today. In an earlier paper [Daly & Djorgovski (2003)] we proposed a novel method to…

Astrophysics · Physics 2009-11-10 Ruth A. Daly , S. G. Djorgovski

A model-independent method to study the possible evolution of dark energy is presented. Optimal estimates of the dark energy equation of state w are obtained from current supernovae data from Riess et al. (2004) following a principal…

Astrophysics · Physics 2007-05-23 Christian Stephan-Otto

The measurement of baryon acoustic oscillations (BAO) from a galaxy redshift survey provides one of the most promising methods for probing dark energy. In this paper, we clarify the assumptions that go into the forecasts of dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-23 Yun Wang

Number counts of galaxy clusters offer a very promising probe of the Dark Energy (DE) equation-of-state parameter, $w$. The basic goal is to measure abundances of these objects as a function of redshift, compare this to a theoretical…

Astrophysics · Physics 2009-09-29 M. Davis , B. F. Gerke , A. L. Coil , M. C. Cooper , R. Yan , J. A. Newman , S. M. Faber , D. Koo , P. Guhathakurta

We examine the validity of the $\Lambda$CDM model, and probe for the dynamics of dark energy using latest astronomical observations. Using the $Om(z)$ diagnosis, we find that different kinds of observational data are in tension within the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Yuecheng Zhang , Hanyu Zhang , Dandan Wang , Yanghan Qi , Yuting Wang , Gong-Bo Zhao

A cosmic shear survey, spanning a significant proportion of the sky, should greatly improve constraints on a number of cosmological parameters. It also provides a unique opportunity to examine the matter power spectrum directly. However,…

Astrophysics · Physics 2009-11-13 Fergus Simpson

We present significant improvements in cosmic distance measurements from the WiggleZ Dark Energy Survey, achieved by applying the reconstruction of the baryonic acoustic feature technique. We show using both data and simulations that the…

The nature of dark energy can be probed not only through its equation of state, but also through its microphysics, characterized by the sound speed of perturbations to the dark energy density and pressure. As the sound speed drops below the…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-25 Roland de Putter , Dragan Huterer , Eric V. Linder

Distance-redshift data can impose strong constraints on dark energy models even when the equation of state is oscillatory. Despite the double integral dependence of the distance on the equation of state, precision measurement of the…

Astrophysics · Physics 2009-11-13 Eric V. Linder

Current surveys may be on the verge of measuring the baryonic oscillations in the galaxy power spectrum which are clearly seen imprinted on the Cosmic Microwave Background. It has recently been proposed that these oscillations allow a…

Astrophysics · Physics 2009-11-10 F. B. Abdalla , S. Rawlings

Measurements of the flux and redshifts of Type Ia supernovae have provided persuasive evidence that the expansion of the universe is accelerating. If true, then in the context of standard FRW cosmology this suggests that the energy density…

Astrophysics · Physics 2007-05-23 David N. Spergel , Glenn D. Starkman
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