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Related papers: The Case for Omega_M = 0.33 +/- 0.035

200 papers

Despite the fact that the mean matter density of the universe has been measured to an accuracy of a few percent within the standard $\Lambda$CDM paradigm, its median density is not known even to order of magnitude. Typical points lie in…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 Jens Stücker , Philipp Busch , Simon D. M. White

We present an analysis of the clustering evolution of dark matter in four cold dark matter (CDM) cosmologies. We use a suite of high resolution, 17-million particle, N-body simulations which sample volumes large enough to give clustering…

In this paper we obtain constraints on the cosmological density parameters, \Omega_m and \Omega_b, by comparing the preliminary measurement of the QSO power spectrum from the two degree field QSO redshift survey with results from an…

Astrophysics · Physics 2009-11-07 Kazuhiro Yamamoto

We compute the joint constraints on ten cosmological parameters from the latest CMB measurements. The lack of a significant second acoustic peak in the latest Boomerang and Maxima data favors models with more baryons than Big Bang…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga

We combine information on cosmological parameters from cluster abundances, CMB primordial anisotropies and the IRAS 1.2 Jy galaxy redshift survey. We take as free parameters the present values of the total matter density of the universe,…

Astrophysics · Physics 2009-10-31 S. L. Bridle , V. R. Eke , O. Lahav , A. N. Lasenby , M. P. Hobson , S. Cole , C. S. Frenk , J. P. Henry

The CMB is already one of the pillars of the Big Bang model. However it may also become our most powerful tool to distinguish contending models and to determine their cosmological parameters. To realize this goal, more than 20 observational…

Astrophysics · Physics 2007-05-23 Charles H. Lineweaver

To re-examine the rich cluster $\Omega$ value the CNOC Cluster Survey has observed 16 high X-ray luminosity clusters in the redshift range 0.17 to 0.55, obtaining approximately 2600 velocities in their fields. Directly adding all the K and…

Astrophysics · Physics 2009-10-28 Carlberg , Yee , Ellingson , Abraham , Gravel , Morris , Pritchet

Light gravitinos of mass $\lesssim \mathcal{O} (10)$ eV are of particular interest in cosmology, offering various baryogenesis scenarios without suffering from the cosmological gravitino problem. The gravitino may contribute considerably to…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-03 Ken Osato , Toyokazu Sekiguchi , Masato Shirasaki , Ayuki Kamada , Naoki Yoshida

A short story of dark matter as an example of a scientific revolution is given. The characteristics of stellar populations are compared with those of dark halos. The mean mass-to-luminosity ratio of stellar populations is found to be 4 in…

Astrophysics · Physics 2007-05-23 J. Einasto , M. Einasto

After two decades of efforts to identify the enigmatic dark matter that comprises the dominant form of matter in our galaxy, the mass range for viable candidates appears to have been reduced by more than 50 orders of magnitude. Positive…

Astrophysics · Physics 2009-10-30 Robert L. Oldershaw

The influence of dark matter particle decay on the baryon-to-photon ratio has been studied for different cosmological epochs. We consider different parameter values of dark matter particles such as mass, lifetime, the relative fraction of…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-03 E. O. Zavarygin , A. V. Ivanchik

We introduce a new method for measuring the Hubble parameter from low-redshift large-scale observations that is independent of the comoving sound horizon. The method uses the baryon-to-photon ratio determined by the primordial deuterium…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 Alex Krolewski , Will J. Percival , Alex Woodfinden

Baryon fraction in clusters, combined with constraints from primordial nucleosynthesis is currently used to provide a robust upper limit on the cosmological density parameter $\Omega_0$. Current analyses lead to gas fractions at virial…

Astrophysics · Physics 2009-11-06 R. Sadat , A. Blanchard

We show that the observed mass-to-light ratio of galaxy clusters increases with cluster temperature as expected from cosmological simulations. Contrary to previous observational suggestions, we find a mild but robust increase of M/L from…

Astrophysics · Physics 2009-06-16 Neta A. Bahcall , Julia M. Comerford

We derive constraints on cosmological parameters and the properties of the lensing galaxies from gravitational lens statistics based on the final Cosmic Lens All Sky Survey (CLASS) data. For a flat universe with a classical cosmological…

We constrain Omega_m through a maximum likelihood analysis of temperatures and redshifts of the high-redshift clusters from the EMSS. We simultaneously fit the low-redshift Markevitch (1998) sample (an all-sky sample from ROSAT with z=0.04-…

Astrophysics · Physics 2009-10-31 Megan Donahue , G. Mark Voit

We perform a joint likelihood analysis of the power spectra of the 2dF Galaxy Redshift Survey (2dFGRS) and the cosmic microwave background (CMB) anisotropies under the assumptions that the initial fluctuations were adiabatic, Gaussian and…

We use Cosmic Microwave Background (CMB) observations together with the Red-sequence Cluster Survey (RCS) weak lensing results to derive constraints on a range of cosmological parameters. This particular choice of observations is motivated…

Astrophysics · Physics 2008-11-26 Carlo R. Contaldi , Henk Hoekstra , Antony Lewis

The most precise determination of the sum of neutrino masses from cosmological data, derived from analysis of the cosmic microwave background (CMB) and baryon acoustic acoustic oscillations (BAO) from the Dark Energy Spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-11 Daniel Green , Joel Meyers

I review the observational data most relevant for large scale structure. These data determine the system of cosmological parameters: the Hubble parameter, densities of various populations of the Universe, parameters characterizing the power…

Astrophysics · Physics 2007-05-23 Jaan Einasto