English
Related papers

Related papers: Constituents of the soft X-ray background

200 papers

Large-scale fluctuations of the X-ray background are investigated using the ROSAT All-Sky Survey. The autocorrelation function of the extragalactic background at 1 keV is determined at separations 0.1 - 40 deg. We detect a significant…

The X-ray background (XRB) is produced by a large number of faint sources distributed over a wide range of redshifts. The XRB carries information on the spatial distribution and evolution of these sources. The goals of the paper are: 1. to…

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

The intensity of the soft X-Ray background is correlated with the distribution of galaxies. To demonstrate this, magnitude limited galaxy samples extracted from bright galaxy catalogues and the Lick counts are utilized. Significant…

The recent deep X-ray surveys at both soft (0.5--2 keV) and hard (2--10 keV) energies have greatly extended our knowledge of the X-ray source density and spectral shapes at relatively faint fluxes adding further evidence on the fact that…

Astrophysics · Physics 2007-05-23 A. Comastri

The deepest observations of the X-ray background approach the surface brightness of the truly diffuse component generated by Thomson scattering of cosmic X-ray photons. Available estimates of the electron density and the X-ray luminosity…

Astrophysics · Physics 2009-11-10 A. M. Soltan

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

The first positive detection of the X-ray background fluctuations at small angular scales is reported. ROSAT PSPC archive pointed observations are used to measure fluctuations at scales of 0.03 - 0.4 deg. The pointings have been selected…

Astrophysics · Physics 2007-05-23 Andrzej M. Soltan , Michael J. Freyberg

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

Small angular scale structure of the soft X-ray background correlated with the galaxy distribution is investigated. An extensive data sample from the ROSAT and XMM-Newton archives are used. Excess emission below 1 keV extending up to at…

Astrophysics · Physics 2007-05-23 A. M. Soltan , M. J. Freyberg , G. Hasinger

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

We present a short overview on the extragalactic background radiation from radio to X-rays, with an eye to the relation to galaxy formation and emphasizing on astrophysical backgrounds (as opposed to cosmological). As the radio background,…

Astrophysics · Physics 2007-05-23 G. De Zotti , A. Franceschini , L. Toffolatti , P. Mazzei , L. Danese

The information content of the autocorrelation function (ACF) of intensity fluctuations of the X-ray background (XRB) is analyzed. The tight upper limits set by ROSAT deep survey data on the ACF at arcmin scales imply strong constraints on…

Astrophysics · Physics 2009-10-22 L. Danese , L. Toffolatti , A. Franceschini , J. M. Martin-Mirones , G. De Zotti

We present the results of our investigation of the composition of the diffuse soft X-ray background emission (SXRB). Combining data of the Leiden/Dwingeloo HI Survey and the ROSAT All-Sky Survey (RASS), we set up a radiation transport…

Astrophysics · Physics 2007-05-23 M. Kappes , J. Pradas , J. Kerp

We present an estimate of the X-ray background (XRB) spectrum from the warm-hot intergalactic medium (IGM) associated with groups and clusters of galaxies, using purely the observationally determined X-ray luminosity function (XLF) and…

Astrophysics · Physics 2009-11-06 Xiang-Ping Wu , Yan-Jie Xue

The shocks produced in the intergalactic medium during large-scale structure formation accelerate a population of highly relativistic electrons which emit synchrotron radiation due to intergalactic magnetic fields. In a previous paper (Loeb…

Astrophysics · Physics 2009-10-31 Eli Waxman , Abraham Loeb

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

Fluctuations of the gamma-ray background (GRB) are investigated. It is assumed that the GRB is produced by discrete sources. Two basic classes of objects as dominant contributors to the GRB are considered: a) blazars and b) starburst…

Astrophysics · Physics 2007-05-23 Andrzej M. Soltan , Radoslaw Marcinkowski

We calculate the angular two-point autocorrelation function (ACF) of the soft X-ray background (SXRB) produced by the warm-hot intergalactic medium (WHIM) associated with dark halos, motivated primarily by searching for missing baryons and…

Astrophysics · Physics 2008-11-26 Xiang-Ping Wu , Yan-Jie Xue

Almost all of the extragalactic X-ray background (XRB) at 0.25 keV can be accounted for by radio-quiet quasars, allowing us to derive an upper limit of 4 \bgunit\ for the remaining background at 0.25 keV. However, the XRB from the gas halos…

Astrophysics · Physics 2009-09-17 K. K. S. Wu , A. C. Fabian , P. E. J. Nulsen

We report the results of a detailed analysis of the contribution of various classes of AGNs to the extragalactic X-ray background (XRB). The model is based on the unification schemes of AGNs and on their related X-ray spectral properties in…

Astrophysics · Physics 2011-05-23 A. Comastri , G. Setti , G. Zamorani , G. Hasinger
‹ Prev 1 2 3 10 Next ›