中文
相关论文

相关论文: Soft X-ray background fluctuations and large-scale…

200 篇论文

The surface density of submillimeter (sub-mm) galaxies as a function of flux, usually termed the source number counts, constrains models of the evolution of the density and luminosity of starburst galaxies. At the faint end of the…

宇宙学与河外天体物理 · 物理学 2015-05-19 M. Zemcov , A. Blain , M. Halpern , L. Levenson

The first systematic study of the serendipitous X-ray source density around 10 high z (0.24<z<1.2) clusters performed with Chandra is presented. A factor \~2 overdensity has been found in 4 cluster fields. The result is statistically highly…

天体物理学 · 物理学 2007-05-23 N. Cappelluti , M. Cappi , M. Dadina , G. Malaguti , M. Branchesi , V. D'Elia , G. G. C. Palumbo

Kashlinsky et al. (2005) find a significant cosmic infrared background fluctuation excess on angular scales >50 arcsec that cannot be explained by instrumental noise or local foregrounds. The excess has been tentatively attributed to…

天体物理学 · 物理学 2009-11-13 R. Salvaterra , M. Magliocchetti , A. Ferrara , R. Schneider

In this paper we investigate the power spectrum of the unresolved 0.5-2 keV CXB with deep Chandra 4 Ms observations in the CDFS. We measured a signal which, on scales >30", is significantly higher than the Shot-Noise and is increasing with…

( 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…

天体物理学 · 物理学 2009-09-25 David N. Spergel , Ue-Li Pen , Marc Kamionkowski , Naoshi Sugiyama

We find that the observed log N - log S relation of X-ray clusters can be reproduced remarkably well with a certain range of values for the fluctuation amplitude $\sigma_8$ and the cosmological density parameter $\Omega_0$ in cold dark…

天体物理学 · 物理学 2009-10-30 Tetsu Kitayama , Yasushi Suto

The cosmic infrared background from galaxies should have a minimum fluctuation of the order of 10\% on angular scales probed by the DIRBE (Diffuse Infrared Background Experiment) on board COBE (Cosmic Background Explorer). We present the…

天体物理学 · 物理学 2007-05-23 A. Kashlinsky , J. C. Mather , S. Odenwald , M. Hauser

We show that Compton scattering by electrons of the hot intergalactic gas in galaxy clusters should lead to peculiar distortions of the cosmic background X-ray and soft gamma-ray radiation - an increase in its brightness at E<60-100 keV and…

高能天体物理现象 · 物理学 2020-04-23 S. A. Grebenev , R. A. Sunyaev

The extragalactic background radiation produced by distant galaxies emitting in the far infrared limits the sensitivity of telescopes operating in this range due to confusion. We have constructed a model of the infrared background based on…

宇宙学与河外天体物理 · 物理学 2017-10-19 S. V. Pilipenko , M. V. Tkachev , A. A. Ermash , T. I. Larchenkova , E. V. Mikheeva , V. N. Lukash

Gravitational lensing by clusters of galaxies affects the cosmic X-ray background (XRB) by altering the observed density and flux distribution of background X-ray sources. At faint detection flux thresholds, the resolved X-ray sources…

天体物理学 · 物理学 2009-10-28 Alexandre Refregier , Abraham Loeb

The source-subtracted, 1.1 and 1.6 {\mu}m NICMOS images used in earlier analyses of the near-infrared Hubble Ultra Deep Field contained residual flux in extended wings of identified sources that contributed an unknown amount to fluctuation…

星系天体物理 · 物理学 2015-06-24 Richard Donnerstein

Spatial Fluctuations in the Cosmic Infrared Background have now been measured out to sub-degree scales showing a strong clustering signal from unresolved sources. We attempt to explain these measurement by considering faint galaxy…

宇宙学与河外天体物理 · 物理学 2015-06-11 Kari Helgason , Massimo Ricotti , Alexander Kashlinsky

Although about 40% of the soft X-ray background emission in 0.4 to 1 keV range has extragalactic origins and thus is totally blocked by the Galactic absorption in midplane directions, it decreases at most by about 20 % in midplane. Suzaku…

天体物理学 · 物理学 2008-10-14 K. Masui , K. Mitsuda , N. Y. Yamasaki , Y. Takei , S. Kimura , T. Yoshino , D. McCammon

The origin of the hard (2-10 keV) X-ray background has remained mysterious for over 35 years. Most of the soft (0.5-2 keV) X-ray background has been resolved into discrete sources, which are primarily quasars; however, these sources do not…

天体物理学 · 物理学 2017-05-10 R. F. Mushotzky , L. L. Cowie , A. J. Barger , K. A. Arnaud

We discuss cosmological inference from galaxy surveys at low and high redshifts. Studies of optical and IRAS redshift surveys with median redshift ${\bar z} \sim 0.02$ yield measurements of the density parameter $\Omega$ and the…

天体物理学 · 物理学 2007-05-23 Ofer Lahav

We examine an ensemble of 48 simulated clusters to determine the effects of small-scale density fluctuations and large-scale substructure on X-ray measurements of the intracluster medium (ICM) mass. We measure RMS density fluctuations in…

天体物理学 · 物理学 2009-10-31 B. Mathiesen , A. E. Evrard , J. J. Mohr

High resolution X-ray imaging offers a unique opportunity to probe the nature of dust in the z ~< 2 universe. Dust grains 0.1- 1 um in size will scatter soft X-rays, producing a diffuse "halo" image around an X-ray point source, with a…

宇宙学与河外天体物理 · 物理学 2015-06-04 Lia Corrales , Frits Paerels

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…

天体物理学 · 物理学 2009-11-10 Stephen Boughn , Robert Crittenden

The large scale distribution of galaxies in the universe displays a complex pattern of clusters, super-clusters, filaments and voids with sizes limited only by the boundaries of the available samples. A quantitative statistical…

宇宙学与河外天体物理 · 物理学 2015-05-20 Francesco Sylos Labini , Luciano Pietronero

We present the X-ray source number counts in two energy bands (0.5-2 and 2-10 keV) from a very large source sample: we combine data of six different surveys, both shallow wide field and deep pencil beam, performed with three different…

天体物理学 · 物理学 2009-11-07 A. Moretti , S. Campana , D. Lazzati , G. Tagliaferri , INAF-O. A. Brera ITALY , IoA Cambridge UK