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Related papers: Large Scale Fluctuations in the X-Ray Background

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The X-Ray Background (XRB) probes structure on scales intermediate between those explored by local galaxy redshift surveys and by the COBE Microwave Background measurements. We predict the large scale angular fluctuations in the XRB,…

Astrophysics · Physics 2015-06-24 Ofer Lahav , Tsvi Piran , Marie A. Treyer

The precision of intensity measurements of the extragalactic X-ray Background (XRB) on an angular scale of about a degree is dominated by spatial fluctuations caused by source confusion noise. X-ray source counts at the flux level…

Astrophysics · Physics 2009-10-30 X. Barcons , A. C. Fabian , F. J. Carrera

( to appear in: Proceedings of the Nishonomiya Yukawa Memorial Symposium Edited by M. Sasaki) There are several models for generating fluctuations in an open universe that are compatible with the microwave background fluctuations detected…

Astrophysics · Physics 2009-09-25 David N. Spergel , Ue-Li Pen , Marc Kamionkowski , Naoshi Sugiyama

Fluctuations of the surface brightness of cosmic X-ray background (CXB) carry unique information about faint and low luminosity source populations, which is inaccessible for conventional large-scale structure (LSS) studies based on resolved…

High Energy Astrophysical Phenomena · Physics 2017-02-01 Alexander Kolodzig , Marat Gilfanov , Gert Hütsi , Rashid Sunyaev

Large-angle fluctuations in the cosmic X-ray background are investigated by a new formalism with a simple model of the X-ray sources. Our method is formulated from the Boltzmann equation and a simple extension of the work by Lahav et al. to…

Astrophysics · Physics 2009-10-30 Yasuhiro Miura , Kazuhiro Yamamoto , Kenta Miyauchi , Masayasu Hosonuma

Recent deep X-ray surveys combined with spectroscopic identification of the sources have allowed the determination of the rest-frame 2-8 keV luminosity as a function of redshift. In addition, an analysis of the HEAO1 A2 2-10 keV full-sky…

Astrophysics · Physics 2009-11-10 Stephen Boughn , Robert Crittenden

We have studied the fluctuations of the soft (0.9-2 keV) X-ray background intensity for ~10 arcmin and ~2 arcmin beam sizes, using 80 high galactic latitude medium-deep images from the ROSAT position sensitive proportional counter (PSPC).…

Astrophysics · Physics 2015-06-24 F. J. Carrera , A. C. Fabian , X. Barcons

We study the cosmic X-ray background (CXB) intensity variations on large angular scales using slew data of the RXTE observatory. We detect intensity variations up to ~2% on angular scales of 20--40deg. These variations are partly correlated…

Astrophysics · Physics 2009-11-13 M. Revnivtsev , S. Molkov , S. Sazonov

The X-ray background is generated by various classes of objects and variety of emission mechanisms. Relative contribution of individual components depends on energy. The goal is to assess the integral emission of the major components of the…

Astrophysics · Physics 2009-11-13 A. M. Soltan

Spatial fluctuations in ultraviolet backgrounds can subtly modulate the distribution of extragalactic sources, a potential signal and systematic for large-scale structure surveys. While this modulation has been shown to be significant for…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-16 Phoebe Upton Sanderbeck , Vid Irsic , Matthew McQuinn , Avery Meiksin

We measure the spatial fluctuations of the Near-Infrared Extragalactic Background Light (NIREBL) from 2$^{\circ}$ to 20$^{\circ}$ in angular scale at the 1.6 and 2.2 $\mu$m using data obtained with Near-Infrared Spectrometer (NIRS) on board…

Astrophysics of Galaxies · Physics 2019-08-14 Min Gyu Kim , Hyung Mok Lee , Woong-Seob Jeong , Kohji Tsumura , Hyungjong Seo , Masahiro Tanaka

We present measurements of the power spectra of cosmic infrared background (CIB) and cosmic microwave background (CMB) fluctuations in six frequency bands. Maps at the lower three frequency bands, 95, 150, and 220 GHz (3330, 2000, 1360…

We study the surface brightness fluctuations of the cosmic X-ray background (CXB) using Chandra data of XBOOTES. After masking out resolved sources we compute the power spectrum of fluctuations of the unresolved CXB for angular scales from…

High Energy Astrophysical Phenomena · Physics 2017-12-06 Alexander Kolodzig , Marat Gilfanov , Gert Hütsi , Rashid Sunyaev

The fluctuations of the cosmic microwave background (CMB) are investigated for a small open universe, i.e., one which is periodically composed of a small fundamental cell. The evolution of initial metric perturbations is computed using the…

Astrophysics · Physics 2009-10-31 Ralf Aurich

New measurements of galaxy clustering and background radiations provide improved constraints on the isotropy and homogeneity of the Universe on large scales. In particular, the angular distribution of radio sources and the X-Ray Background…

Astrophysics · Physics 2009-10-16 Kelvin K. S. Wu , Ofer Lahav , Martin J. Rees

Fluctuations of the soft X-ray background are investigated using harmonic analysis. A section of the ROSAT All-Sky Survey around the north galactic pole is used. The flux distribution is expanded into a set of harmonic functions and the…

Astrophysics · Physics 2009-11-07 W. Sliwa , A. M. Soltan , M. J. Freyberg

We cross correlate the large-scale cosmic microwave background (CMB) sky measured by WMAP with two probes of large-scale structure at z ~ 1. The hard X-ray background, measured by the HEAO-1 satellite, is positively correlated with the WMAP…

Astrophysics · Physics 2008-11-26 Stephen Boughn , Robert Crittenden

We compare the amplitudes of fluctuations probed by the 2dF Galaxy Redshift Survey and by the latest measurements of the Cosmic Microwave Background anisotropies. By combining the 2dFGRS and CMB data we find the linear-theory rms mass…

We propose a new, simple, dedicated X-ray mission to measure the power spectrum of density fluctuations in the Universe, by accurately mapping the X-ray background on the whole sky on scales of arounf one sq deg. Since the method relies on…

Astrophysics · Physics 2015-06-24 X. Barcons , A. C. Fabian

In universes with significant curvature or cosmological constant, cosmic microwave background (CMB) anisotropies are created very recently via the Rees-Sciama or integrated Sachs-Wolfe effects. This causes the CMB anisotropies to become…

Astrophysics · Physics 2009-10-30 S. P. Boughn , R. G. Crittenden , N. G. Turok
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