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While large scale cosmic microwave background (CMB) anisotropies involve a combination of the scalar and tensor fluctuations, the scalar amplitude can be independently determined through the CMB-galaxy cross-correlation. Using recently…

Astrophysics · Physics 2008-11-26 A. Cooray , P. S. Corasaniti , T. Giannantonio , A. Melchiorri

We investigate the anisotropies in the cosmic microwave background in a class of models which possess a positive cosmic energy density but negative pressure, with a constant equation of state w = p/rho < -1. We calculate the temperature and…

Astrophysics · Physics 2009-07-09 A. E. Schulz , Martin White

Observations of the solar radio emission in the microwave frequency range show fine structures consisting of a number of the almost parallel narrow frequency bands. We interpret these bands as the cyclotron harmonics plasma emission. This…

Astrophysics · Physics 2015-06-24 V. G. Ledenev , M. Karlicky , Y. Yan , Q. Fu

It is commonly assumed that the stochastic background of gravitational waves on cosmological scales follows an almost scale-independent power spectrum, as generically predicted by the inflationary paradigm. However, it is not inconceivable…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-14 Jan Hamann , Ameek Malhotra

Recent measurements of the Cosmic Microwave Background Anisotropy have provided evidence for the presence of oscillations in the angular power spectrum. These oscillations are a wonderful confirmation of the standard cosmological scenario…

Astrophysics · Physics 2007-05-23 Alessandro Melchiorri

Primordial magnetic fields present since before the epoch of matter-radiation equality have an effect on the anisotropies of the cosmic microwave background. The CMB anisotropies due to scalar perturbations are calculated in the gauge…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 Kerstin E. Kunze

Recently the lower bounds of the intergalactic magnetic fields $10^{-16} \sim 10^{-20}$ Gauss are set by gamma-ray observations while it is unlikely to generate such large scale magnetic fields through astrophysical processes. It is known…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-17 Shohei Saga , Maresuke Shiraishi , Kiyotomo Ichiki , Naoshi Sugiyama

The existence of large-scale anisotropy can not be ruled out by the cosmic microwave background (CMB) radiation. Over the years, several models have been proposed in the context of anisotropic inflation to account for CMB's cold spot and…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-15 Sourav Pal , Debaprasad Maity , Tuan Q. Do

We report on a measurement of the angular power spectrum of the anisotropy in the Cosmic Microwave Background. The anisotropy is measured in 23 different multipole bands from l=54 (~3 deg) to l=404 (~0.45 deg) and in 6 frequency bands from…

Astrophysics · Physics 2009-10-28 C. B. Netterfield , M. J. Devlin , N. Jarosik , L. Page , E. J. Wollack

The cosmological magnetic field is one of the important physical quantities which affect strongly the cosmic microwave background (CMB) power spectrum. Recent CMB observations have been extended to higher multipoles $l\gtrsim$1000, and they…

Astrophysics · Physics 2009-11-10 D. G. Yamazaki , K. Ichiki , T. Kajino

We detect anisotropy in the cosmic microwave background (CMB) at degree angular scales and confirm a previous detection reported by Wollack et al. (1993). The root-mean-squared amplitude of the fluctuations is $44^{+13}_{-7} \mu$K. This may…

Astrophysics · Physics 2008-11-26 C. B. Netterfield , N. Jarosik , L. Page , D. Wilkinson , E. Wollack

The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history,…

Using the Parker Solar Probe data taken in the inner heliosphere, we investigate the power and spatial anisotropy of magnetic-field spectra at kinetic scales (i.e., around sub-ion scales) in solar wind turbulence in the inner heliosphere.…

Solar and Stellar Astrophysics · Physics 2022-04-20 S. Y. Huang , S. B. Xu , J. Zhang , F. Sahraoui , N. Andres , J. S. He , Z. G. Yuan , X. H. Deng , K. Jiang , Y. Y. Wei , Q. Y. Xiong , Z. Wang , L. Yu , R. T. Lin

In this work we investigate the effects of the primordial magnetic fields on cosmic microwave background anisotropies (CMB). Based on cosmological magnetohydrodynamic (MHD) simulations we calculate the CMB anisotropy spectra and…

Astrophysics · Physics 2009-11-13 Hiroyuki Tashiro , Naoshi Sugiyama , Robi Banerjee

Fluctuations in the Galactic synchrotron emission can be traced by the angular power spectrum of radio maps at low multipoles. At frequencies below few GHz, large-scale anisotropies are mainly induced by magnetic field turbulence. By…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Marco Regis

The arrival directions of multi-TeV cosmic rays show significant anisotropies at small angular scales. It has been argued that this small scale structure is reflecting the local, turbulent magnetic field in the presence of a global dipole…

High Energy Astrophysical Phenomena · Physics 2015-12-01 Philipp Mertsch , Markus Ahlers

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

Angular power spectrum of the cosmic microwave background (CMB) temperature anisotropies is one of the most important on characteristics of the Universe such as its geometry and total density. Using flat sky approximation and Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

We derive the implications for anisotropies in the cosmic microwave background following from a model of inflation in which a bare cosmological constant is gradually screened by an infrared process in quantum gravity. The model predicts…

Astrophysics · Physics 2015-06-24 L. R. Abramo , N. C. Tsamis , R. P. Woodard

Since the energy momentum tensor of a magnetic field always contains a spin-2 component in its anisotropic stress, stochastic primordial magnetic field (PMF) in the early universe must generate stochastic gravitational wave (GW) background.…

Astrophysics · Physics 2010-01-27 Shuang Wang