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A recent study of the rotation of the plane of polarization of light from 160 cosmological sources claims to find significant evidence for cosmological anisotropy. We point out methodological weaknesses of that study, and reanalyze the same…

Astrophysics · Physics 2009-12-30 Thomas J. Loredo , Eanna E. Flanagan , Ira M. Wasserman

The cosmological principle is fundamental to the standard cosmological model. It assumes that the Universe is homogeneous and isotropic on very large scales. As the basic assumption, it must stand the test of various observations. In this…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-13 J. P. Hu , Y. Y. Wang , J. Hu , F. Y. Wang

First results of a Cosmic Microwave Background (CMB) anisotropy experiment conducted at the Observatorio del Teide (Tenerife, Spain) are presented. The instrument is a four channel (3.1, 2.1, 1.3 and 1.1 mm) $^3$He bolometer system coupled…

We examine the extent to which galactic and extragalactic foregrounds can hamper the detection of primordial Cosmic Microwave Background (CMB) anisotropies. We limit our discussion to intermediate angular scales, $10^{\prime}\lsim \theta…

Astrophysics · Physics 2009-09-25 L. Toffolatti

In this article we focus on the astrophysical results and the related cosmological implications derived from recent microwave surveys, with emphasis to those coming from the Planck mission. We critically discuss the impact of systematics…

The Cosmic Infrared Background Experiment (CIBER) is a suite of four instruments designed to study the near infrared (IR) background light from above the Earth's atmosphere. The instrument package comprises two imaging telescopes designed…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 M. Zemcov , T. Arai , J. Battle , J. Bock , A. Cooray , V. Hristov , B. Keating , M. G. Kim , D. H. Lee , L. R. Levenson , P. Mason , T. Matsumoto , S. Matsuura , U. W. Nam , T. Renbarger , I. Sullivan , K. Suzuki , K. Tsumura , T. Wada

A priori, cosmic-ray measurements offer a unique capability to determine the vertical profile of atmospheric temperatures directly from ground. However, despite the increased understanding of the impact of the atmosphere on cosmic-ray…

Atmospheric and Oceanic Physics · Physics 2021-12-10 Riádigos Irma , González-Díaz Diego , Pérez-Muñuzuri Vicente

Observations of the microwave sky using the Python telescope in its fifth season of operation at the Amundsen-Scott South Pole Station in Antarctica are presented. The system consists of a 0.75 m off-axis telescope instrumented with a HEMT…

This is the obligatory Cosmic Microwave Background review. I discuss the current status of CMB anisotropies, together with some points on the related topic of the Far-Infrared Background. We have already learned a number of important things…

Astrophysics · Physics 2007-05-23 Douglas Scott

We derive upper and lower limits for the basic physical parameters (mass-radius ratio, anisotropy, redshift and total energy) for arbitrary anisotropic general relativistic matter distributions in the presence of a cosmological constant.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. G. Boehmer , T. Harko

The scalar mode temperature fluctuations of the cosmic microwave background has been derived in a spatially closed universe from two different methods. First, by following the photon trajectory after the last scattering and then from the…

General Relativity and Quantum Cosmology · Physics 2017-09-27 Pedram Niazy , Amir H. Abbassi

We present an exact solution of the anisotropies of cosmic background radiation (CBR) from a local collapse described by a spherical over-dense region embedded in a flat universe, with the emphasis on the relationship between the dipole…

Astrophysics · Physics 2009-10-22 Xiang-Ping Wu , Li-Zhi Fang

Identifying the anisotropies in a cosmologically sourced stochastic gravitational wave background (SGWB) would be of significance in shedding light on the nature of primordial inhomogeneities. For example, if SGWB carries isocurvature…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-18 Yanou Cui , Soubhik Kumar , Raman Sundrum , Yuhsin Tsai

Scaling properties of the cosmic microwave background (CMB) radiation are studied using satellite (COBE-DMR maps), balloon-borne and ground-based (combined QMASK map) data. Quantitative consistency is found between the multiscaling…

Astrophysics · Physics 2009-11-07 A. Bershadskii

y-type spectral distortions of the cosmic microwave background allow us to detect clusters and groups of galaxies, filaments of hot gas and the non-uniformities in the warm hot intergalactic medium. Several CMB experiments (on small areas…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-13 Rashid A. Sunyaev , Rishi Khatri

We present the first targeted measurement of the power spectrum of anisotropies of the radio synchrotron background, at 140 MHz where it is the overwhelmingly dominant photon background. This measurement is important for understanding the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-06 A. R. Offringa , J. Singal , S. Heston , S. Horiuchi , D. M. Lucero

The spectral variation of the cosmic microwave background (CMB) as observed by WMAP was tested using foreground reduced WMAP5 data, by producing subtraction maps at the 1$^\circ$ angular resolution between the two cosmological bands of V…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Bi-Zhu Jiang , Richard Lieu , Shuang-Nan Zhang , Bart Wakker

This work presents a summary of major cosmological results from the COBE (Cosmic Background Explorer) satellite mission. The results include a precise measurement of the Cosmic Microwave Background (CMB) radiation intensity, discovery and…

Astrophysics · Physics 2009-10-31 George F. Smoot

In the standard cosmological model, the temperature anisotropy of the cosmic microwave background is interpreted as variation in the gravitational potential at the point of emission, due to the emitter being embedded in a region ${\cal C}$…

Astrophysics · Physics 2007-05-23 Richard Lieu

The atmospheres of planets (including Earth) and the outer layers of stars have often been treated in radiative transfer as plane-parallel media, instead of spherical shells, which can lead to inaccuracy, e.g. limb darkening. We give an…

Statistical Mechanics · Physics 2009-11-11 Michael J. Caola
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