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Under the assumption that the concordance Lambda cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with…

天体物理学 · 物理学 2007-05-23 Louise M. Griffiths , Charles H. Lineweaver

The high-significance measurement of large-scale structure signals enables testing the isotropy of the Universe. The measurement of cosmological parameters through the large-scale distribution of matter is now a mature domain. This approach…

宇宙学与河外天体物理 · 物理学 2017-02-01 G. Hurier

In this paper, we investigate the cosmic anisotropy from the SN-Q sample, consisting of the Pantheon sample and quasars, by employing the hemisphere comparison (HC) method and the dipole fitting (DF) method. Compared to the Pantheon sample,…

宇宙学与河外天体物理 · 物理学 2020-11-18 J. P. Hu , Y. Y. Wang , F. Y. Wang

Measurements of the cosmic microwave background (CMB) spectral $y$-distortion anisotropy offer a test for the statistical isotropy of the primordial density perturbations on $0.01\lesssim k{\rm Mpc}\lesssim 1$. We compute the 1-point…

宇宙学与河外天体物理 · 物理学 2019-01-28 Atsuhisa Ota

The presence of a dipolar statistical anisotropy in the spectrum of cosmic microwave background (CMB) fluctuations was reported by the Wilkinson Microwave Anisotropy Probe (WMAP), and has recently been confirmed in the Planck 2013 analysis…

宇宙学与河外天体物理 · 物理学 2014-04-29 Sugumi Kanno , Misao Sasaki , Takahiro Tanaka

Sparse inpainting techniques are gaining in popularity as a tool for cosmological data analysis, in particular for handling data which present masked regions and missing observations. We investigate here the relationship between sparse…

宇宙学与河外天体物理 · 物理学 2014-02-03 Stephen M. Feeney , Domenico Marinucci , Jason D. McEwen , Hiranya V. Peiris , Benjamin D. Wandelt , Valentina Cammarota

The ellipticity of the anisotropy spots of the Cosmic Microwave Background measured by the Wilkinson Microwave Anisotropy Probe (WMAP) has been studied. We find an average ellipticity of about 2, confirming with a far larger statistics…

We analyze first-year data of WMAP to determine the significance of asymmetry in summed power between arbitrarily defined opposite hemispheres, using maps that we create ourselves with software developed independently of the WMAP team. We…

天体物理学 · 物理学 2010-11-11 P. E. Freeman , C. R. Genovese , C. J. Miller , R. C. Nichol , L. Wasserman

Several anomalies appear to be present in the large-angle cosmic microwave background (CMB) anisotropy maps of WMAP, including the alignment of large-scale multipoles. Models in which isotropy is spontaneously broken (e.g., by a scalar…

宇宙学与河外天体物理 · 物理学 2015-03-13 Haoxuan Zheng , Emory F. Bunn

The cosmic radio dipole is an anisotropy in the number counts of radio sources, analogous to the dipole seen in the cosmic microwave background (CMB). Measurements of source counts of large radio surveys have shown that though the radio…

宇宙学与河外天体物理 · 物理学 2023-07-05 J. D. Wagenveld , H-R. Klöckner , D. J. Schwarz

The angular two-point correlation function of the temperature of the cosmic microwave background (CMB), as inferred from nearly all-sky maps, is very close to zero on large angular scales. A statistic invented to quantify this feature,…

宇宙学与河外天体物理 · 物理学 2017-05-04 Robert Knight , Lloyd Knox

We study the apparent lack of power on large angular scales in the WMAP data. We confirm that although there is no apparent lack of power at large angular scales for the full-sky maps, the lowest multipoles of the WMAP data happen to have…

天体物理学 · 物理学 2007-05-23 Amir Hajian

We propose several pseudoentropy measures that agree well with the Wehrl entropy, but are significantly faster to compute. All of them are rotationally invariant measures of entanglement very sensitive to non-Gaussianity, anisotropy, and…

宇宙学与河外天体物理 · 物理学 2019-05-06 Momchil Minkov , Marvin Pinkwart , Peter Schupp

We have simulated cosmic microwave background (CMB) anisotropy maps for several COBE-DMR-normalized cold dark matter (CDM) cosmogonies, to make predictions for the upcoming MAP experiment. We have studied the sensitivity of the simulated…

Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII_h templates in the CMB anisotropy…

天体物理学 · 物理学 2008-11-26 Tuhin Ghosh , Amir Hajian , Tarun Souradeep

We use a recent Pantheon+SH0ES compilation of Type Ia Supernova distance measurements at low-redshift, i.e., $0.01 \leq z \leq 0.10$, in order to investigate the directional dependency of the deceleration parameter ($q_0$) in different…

宇宙学与河外天体物理 · 物理学 2024-06-27 Carlos A. P. Bengaly , Cássio Pigozzo , Jailson S. Alcaniz

Full-sky maps of the cosmic microwave background temperature reveal a 7% asymmetry of fluctuation power between two halves of the sky. A common phenomenological model for this asymmetry is an overall dipole modulation of statistically…

宇宙学与河外天体物理 · 物理学 2015-10-07 Simone Aiola , Bingjie Wang , Arthur Kosowsky , Tina Kahniashvili , Hassan Firouzjahi

The dipole anisotropy seen in the {cosmic microwave background radiation} is interpreted as due to our peculiar motion. The Cosmological Principle implies that this cosmic dipole signal should also be present, with the same direction, in…

宇宙学与河外天体物理 · 物理学 2019-04-24 Carlos A. P. Bengaly , Thilo M. Siewert , Dominik J. Schwarz , Roy Maartens

Breakdown of rotational invariance of the primordial power spectrum manifests in the statistical anisotropy of the observed Cosmic Microwave Background (CMB) radiation. Hemispherical power asymmetry in the CMB may be caused due to a dipolar…

宇宙学与河外天体物理 · 物理学 2023-05-23 Md Ishaque Khan , Rajib Saha

We examine the degree to which observations of large-scale cosmic microwave background (CMB) polarization can shed light on the puzzling large-scale power modulation in maps of CMB anisotropy. We consider a phenomenological model in which…

宇宙学与河外天体物理 · 物理学 2016-11-23 Emory F. Bunn , Qingyang Xue , Haoxuan Zheng