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Related papers: Bianchi VII_h models and the cold spot texture

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We show that the B-mode polarization signal detected at low multipoles by BICEP2 cannot be entirely due to topological defects. This would be incompatible with the high-multipole B-mode polarization data and also with existing temperature…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-07 Joanes Lizarraga , Jon Urrestilla , David Daverio , Mark Hindmarsh , Martin Kunz , Andrew R. Liddle

Space-times which allow a slicing into homogeneous spatial hypersurfaces generalize the usual Bianchi models. One knows already that in these models the Bianchi type may change with time. Here we show which of the changes really appear. To…

General Relativity and Quantum Cosmology · Physics 2009-10-28 M. Rainer , H. -J. Schmidt

We report the serendipitous discovery of a 7-s X-ray pulsar using data acquired with the Advanced Satellite for Cosmology and Astrophysics. The pulsar is detected as an unresolved source located towards a region of the Galactic plane (l,b ~…

Astrophysics · Physics 2009-10-30 E. V. Gotthelf , G. Vasisht

In earlier works, it was shown that the energy dependent soft time lags observed in kHz QPOs of neutron star low mass X-ray binaries (LMXBs) can be explained as being due to Comptonization lags provided a significant fraction ($\eta \sim…

High Energy Astrophysical Phenomena · Physics 2016-07-15 Nagendra Kumar , Ranjeev Misra

The large-angular-scale falloff in the autocorrelation function for the cosmic microwave background (CMB) temperature has long intrigued cosmologists and fueled speculation about suppressed superhorizon power. Here we highlight an…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-13 Jahmour J. Givans , Marc Kamionkowski

Temperature maps are presented of the 9 largest clusters in the mock catalogues of Muanwong et al. for both the Preheating and Radiative models. The maps show that clusters are not smooth, featureless systems, but contain a variety of…

Astrophysics · Physics 2009-11-07 Lesley I. Onuora , Scott T. Kay , Peter A. Thomas

Anomalies in the large-scale CMB temperature sky measured by WMAP have been suggested as possible evidence for a violation of statistical isotropy on large scales. In any physical model for broken isotropy, there are testable consequences…

Astrophysics · Physics 2008-12-18 Cora Dvorkin , Hiranya V. Peiris , Wayne Hu

The Cold Spot (CS) is a clear feature in the Cosmic Microwave Background (CMB); it could be of primordial origin, or caused by a intervening structure along the line of sight. We identified a large projected underdensity in the recently…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Fabio Finelli , Juan Garcia-Bellido , Andras Kovacs , Francesco Paci , Istvan Szapudi

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce…

Astrophysics · Physics 2009-11-10 Simon Prunet , Jean-Philippe Uzan , Francis Bernardeau , Tristan Brunier

We find a significant CMB temperature excess in the direction of local underdensities within $z<0.03$. By contrast, less than $0.2\%$ of simulated CMB maps show a similarly significant temperature excess in nearby voids. Combined with…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-29 Frode K. Hansen , Diego Garcia Lambas , Andrés N. Ruiz , Facundo Toscano , Luis A. Pereyra

We present the results of numerical experiments to assess degeneracies in lightcurve models of starspots. Using synthetic lightcurves generated with the Cheetah starspot modeling code, we explore the extent to which photometric light curves…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Lucianne M. Walkowicz , Gibor S. Basri , Jeff A. Valenti

The correlation of weak lensing and Cosmic Microwave Anisotropy (CMB) data traces the pressure distribution of the hot, ionized gas and the underlying matter density field. The measured correlation is dominated by baryons residing in halos.…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-23 F. Atrio-Barandela , J. P. Mücket

Single-field inflation, arguably the simplest and most compelling paradigm for the origin of our Universe, is strongly supported by the recent results of the Planck satellite and the BICEP2 experiment. The results from Planck, however, also…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Juan C. Bueno Sanchez

We use the high quality pressure profiles of 239 galaxy clusters made available by the ACCEPT project (Cavagnolo et al. 2009) in order to derive the expected Sunyaev Zeldovich (SZ) signal in a variety of cases that hardly find a counterpart…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 A. Pipino , E. Pierpaoli

We use the local curvature to investigate the possible existence of non-Gaussianity/asymmetry in the WMAP data. Considering the full sky we find results which are consistent with the Gaussian assumption. However, strong non-Gaussian…

Astrophysics · Physics 2010-04-06 Frode K. Hansen , Paolo Cabella , Domenico Marinucci , Nicola Vittorio

We revisit the problem of thermal bulge of asynchronous hot Jupiters, using HD 209458 b as a fiducial study. We improve upon previous works by using a double-gray atmosphere model and interior structure from MESA as the background state,…

Earth and Planetary Astrophysics · Physics 2020-01-08 Pin-Gao Gu , Da-Kai Peng , Chien-Chang Yen

We revisit the claimed detection of a new cosmic microwave background (CMB) foreground based on the correlation between low-redshift 2MASS Redshift Survey (2MRS) galaxies and CMB temperature maps from the Planck and WMAP missions. We…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-03 Graeme E. Addison

We propose a "feature-scattering" mechanism to explain the cosmic microwave background cold spot seen from WMAP and Planck maps. If there are hidden features in the potential of multi-field inflation, the inflationary trajectory can be…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-02 Yi Wang , Yin-Zhe Ma

We present the first Bayesian constraints on the single field inflationary reheating era obtained from Cosmic Microwave Background (CMB) data. After demonstrating that this epoch can be fully characterized by the so-called reheating…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jerome Martin , Christophe Ringeval

Recent advancements have shown tensions between observations and our current understanding of the Universe. Such observations may include the $H_o$ tension and massive galaxies at high redshifts that are older than what traditional galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-16 Lior Shamir