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Polarization measures, on wide angular scales, together with anisotropy data, can fix DE parameters. Here we discuss the sensitivity needed to provide significant limits. Our analysis puts in evidence that a class of models predicts low…

Astrophysics · Physics 2007-05-23 L. P. L. Colombo , R. Mainini , S. A. Bonometto

We study properties of dark matter halos in a variety of models which include Dark Energy (DE). We consider both DE due to a scalar field self--interacting through Ratra-Peebles or SUGRA potentials, and DE with constant negative w=p\rho…

Astrophysics · Physics 2009-11-07 A. Klypin , A. V. Maccio' , R. Mainini , S. A. Bonometto

We use WMAP5 and other cosmological data to constrain model parameters in quintessence cosmologies, focusing also on their shift when we allow for non-vanishing neutrino masses. The Ratra-Peebles (RP) and SUGRA potentials are used here, as…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 G. La Vacca , J. R. Kristiansen

Upcoming Weak Lensing (WL) surveys can be used to constrain Dark Energy (DE) properties, namely if tomographic techniques are used to improve their sensitivity. In this work, we use a Fisher matrix technique to compare the power of CMB…

Astrophysics · Physics 2009-06-23 G. La Vacca , L. P. L. Colombo

The lack of power anomaly is an intriguing feature at the largest angular scales of the CMB anisotropy temperature pattern, whose statistical significance is not strong enough to claim any new physics beyond the standard cosmological model.…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-11 M. Billi , A. Gruppuso , N. Mandolesi , L. Moscardini , P. Natoli

We study the effects of dark energy (DE) anisotropic stress on features of the matter power spectrum (PS). We employ the Parametrized Post-Friedmannian (PPF) formalism to emulate an effective DE, and model its anisotropic stress properties…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-09 Gabriela Garcia-Arroyo , Jorge L. Cervantes-Cota , Ulises Nucamendi , Alejandro Aviles

The Wilkinson Microwave Anisotropy Probe (WMAP) has mapped the full sky in Stokes I, Q, and U parameters at frequencies 23, 33, 41, 61, and 94 GHz. We detect correlations between the temperature and polarization maps significant at more…

Astrophysics · Physics 2015-06-24 A. Kogut

For a track based polarimeter, such as the Imaging X-ray Polarimetry Explorer (IXPE), the sensitivity to polarization depends on the modulation factor, which is a strong function of energy. In previous work, a likelihood method was…

Instrumentation and Methods for Astrophysics · Physics 2021-09-29 Herman L. Marshall

The simplest inflationary models predict a primordial power spectrum (PPS) of the curvature fluctuations that can be described by a power-law function that is nearly scale-invariant. It has been shown, however, that the low-multipole…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Eleonora Di Valentino , Stefano Gariazzo , Martina Gerbino , Elena Giusarma , Olga Mena

Accurate measurements of fundamental cosmological parameters, especially the Hubble constant (H_0) and present-day matter density (\Omega_{m0}), are crucial for constraining dark energy (DE) evolution. We analyze the sensitivities of…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-24 Seokcheon Lee

In this paper, we investigate the possibility of testing the weakly interacting massive particle (WIMP) dark matter (DM) models by applying the simplest phenomenological model which introduces an interaction term between dark energy (DE)…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-15 Wei Cheng , Yuan He , Jin-Wang Diao , Yu Pan , Jun Zeng , Jia-Wei Zhang

This paper focuses on cosmological constraints derived from analysis of WMAP data alone. A simple LCDM cosmological model fits the five-year WMAP temperature and polarization data. The basic parameters of the model are consistent with the…

Precise measurements of the Cosmic Microwave Background (CMB) anisotropy have been one of the foremost concerns in modern cosmology as it provides valuable information on the cosmology of the universe. However, an accurate estimation of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-20 Fidy A. Ramamonjisoa , Subharthi Ray , Sanjit Mitra , Tarun Souradeep

We introduce a convenient parametrization of dark energy models that is general enough to include several modified gravity models and generalized forms of dark energy. In particular we take into account the linear perturbation growth…

Astrophysics · Physics 2009-06-23 Luca Amendola , Martin Kunz , Domenico Sapone

The angular power spectrum of the cosmic microwave background temperature anisotropy observed by WMAP has an anomalous dip at l~20 and bump at l~40. One explanation for this structure is the presence of features in the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-19 Michael J. Mortonson , Cora Dvorkin , Hiranya V. Peiris , Wayne Hu

Interacting dark energy models have been suggested as alternatives to the standard cosmological model, $\Lambda$CDM. We focus on a phenomenologically interesting class of dark scattering models that is characterised by pure momentum…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 Maria Tsedrik , Chiara Moretti , Pedro Carrilho , Federico Rizzo , Alkistis Pourtsidou

When CMB data are used to derive cosmological parameters, their very choice does matter: some parameter values can be biased if the parameter space does not cover the "true" model. This is a problem, because of the difficulty to parametrize…

Astrophysics · Physics 2009-06-23 Giuseppe La Vacca , Loris P. L. Colombo , Luca Vergani , Silvio A. Bonometto

The latest data release from the ACT CMB experiment (in combination with previous WMAP data) shows evidence for an Early Dark Energy component at more than $3$ standard deviations. The same conclusion has been recently shown to hold when…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-27 Emanuele Fondi , Alessandro Melchiorri , Luca Pagano

We consider the prospects to use polarized dark-matter detectors to discriminate between various dark-matter models. If WIMPs are fermions and participate in parity-violating interactions with ordinary matter, then the recoil-direction and…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-20 Chi-Ting Chiang , Marc Kamionkowski , Gordan Z. Krnjaic

We investigate the impact of non-linear corrections on dark energy parameter estimation from weak lensing probes. We find that using halofit expressions, suited to LCDM models, implies substantial discrepancies with respect to results…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Luciano Casarini , Giuseppe La Vacca , Luca Amendola , Silvio A. Bonometto , Andrea V. Macciò
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