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We estimate the contributions to the cosmic microwave background radiation (CMBR) power spectrum from the static and kinematic Sunyaev-Zel'dovich (SZ) effects, and from the moving cluster of galaxies (MCG) effect. We conclude, in agreement…

Astrophysics · Physics 2009-10-31 S. M. Molnar , M. Birkinshaw

During cosmic recombination, charged particles bind into neutral atoms and the mean free path of photons rapidly increases, resulting in the familiar diffusion damping of primordial radiation temperature variations. An additional effect is…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-04 Nathaniel Starkman , Glenn Starkman , Arthur Kosowsky

The cosmological implications from a new estimate of the local X-ray galaxy cluster abundance are summarized. The results are then compared to independent observations. It is suggested that `low' values for the mean cosmic matter density…

Astrophysics · Physics 2007-05-23 Thomas H. Reiprich

We present our results on multiplicity and $p_T$ fluctuations at LHC energies in the framework of the clustering of color sources. In this approach, elementary color sources -strings- overlap forming clusters, so the number of effective…

High Energy Physics - Phenomenology · Physics 2007-06-22 L. Cunqueiro , E. G. Ferreiro , C. Pajares

The detection and characterization of the physical properties of very distant galaxies will be one the prominent science case of all future Extremely Large Telescopes, including the 39m E-ELT. Multi-Object Spectroscopic instruments are…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 M. Puech , H. Flores , Y. B. Yang , M. Rodrigues , T. Gonçalves , F. Hammer , K. Disseau

Today's sensitive, high-resolution X-ray observations allow the study of populations of X-ray sources, in the luminosity range of Galactic X-ray binaries, in galaxies as distant as 20-30 Mpc. The traditional astronomical tools of…

Astrophysics · Physics 2009-11-13 G. Fabbiano

The origin of the X-ray background spectral intensity has been a long standing problem in high energy astrophysics research. Deep X-ray surveys carried out with ROSAT and ASCA combined with the broad band spectral results of Ginga and…

Astrophysics · Physics 2007-05-23 Andrea Comastri

Angular fluctuations of stochastic gravitational wave backgrounds (GWB) produced by extragalactic astrophysical sources are calculated. The angular properties of such backgrounds are determined by the large scale structure of Universe…

Astrophysics · Physics 2007-05-23 D. I. Kosenko , K. A. Postnov

We study the evolution of cosmological perturbations in a non-singular bouncing cosmology with a bounce phase which has superimposed oscillations of the scale factor. We identify length scales for which the final spectrum of fluctuations…

High Energy Physics - Theory · Physics 2018-02-14 Robert Brandenberger , Qiuyue Liang , Rudnei O. Ramos , Siyi Zhou

Working by analogy, we use the description of light fluctuations due to random collisions of the radiating atoms to figure out why the reduction of the coherence for light propagating a cosmological distance in the fluctuating background…

General Relativity and Quantum Cosmology · Physics 2016-12-30 Michael Maziashvili

On small scales the observable Universe is highly inhomogeneous, with galaxies and clusters forming a complex web of voids and filaments. The optical properties of such configurations can be quite different from the perfectly smooth…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Viraj A. A. Sanghai , Pierre Fleury , Timothy Clifton

Cosmic magnification is due to the weak gravitational lensing of sources in the distant Universe by foreground large-scale structure leading to coherent changes in the observed number density of the background sources. Depending on the…

Cosmic photons can be efficiently collected by broadband intensity mapping but information on their emission redshift and frequency is largely lost. We introduce a technique to statistically recover these otherwise collapsed dimensions by…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-12 Yi-Kuan Chiang , Brice Ménard , David Schiminovich

Lyman-alpha forest data probing the post-reionization Universe shows surprisingly large opacity fluctuations over rather large ($\ge$50 comoving Mpc/h) spatial scales. We model these fluctuations using a hybrid approach utilizing the large…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-21 Jonathan Chardin , Ewald Puchwein , Martin G. Haehnelt

The flux and nuclear composition of ultra-high energy cosmic rays depend on the cosmic distribution of their sources. Data from cosmic ray observatories are yet inconclusive about their exact location or distribution, but provide a measure…

High Energy Astrophysical Phenomena · Physics 2013-05-30 Markus Ahlers , Luis A. Anchordoqui , Andrew M. Taylor

Quantum fluctuations of lightcone are examined in a 4-dimensional spacetime with two parallel planes. Both the Dirichlet and the Neumann boundary conditions are considered. In all the cases we have studied, quantum lightcone fluctuations…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Hongwei Yu , Pu-Xun Wu

The detection of a time variation of the angle between two distant sources would reveal an anisotropic expansion of the Universe. We study this effect of "cosmic parallax" within the "ellipsoidal universe" model, namely a particular…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-29 L. Campanelli , P. Cea , G. L. Fogli , L. Tedesco

In many astrophysical systems, smoothly-varying large-scale variations coexist with small-scale fluctuations. For example, a large-scale velocity or density gradient can exist in molecular clouds that exhibit small-scale turbulence. In…

Instrumentation and Methods for Astrophysics · Physics 2017-10-20 Jungyeon Cho

In this review, I outline the use of galaxy correlations to constrain cosmological parameters. As with the Cosmic Microwave Background (CMB), the density of dark and baryonic matter imprints important scales on the fluctuations of matter…

Astrophysics · Physics 2008-11-26 Robert C. Nichol

General asymptotic formulas are given for the coefficient $C_\ell$ of the term of multipole number $\ell$ in the temperature correlation function of the cosmic microwave background, in terms of scalar and dipole form factors introduced in a…

Astrophysics · Physics 2009-11-06 Steven Weinberg