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Related papers: Constituents of the soft X-ray background

200 papers

We present a cross-correlation analysis to constrain the faint galaxy contribution to the cosmic X-ray background (XRB). Cross-correlating faint optical galaxy catalogues with unidentified X-ray sources from 3 deep ROSAT fields we find that…

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

We compute the hard X-ray spectra from a hot plasma pervaded by small cold dense clouds. The main cooling mechanism of the plasma is Compton cooling by the soft thermal emission from the clouds. We compute numerically the equilibrium…

Astrophysics · Physics 2009-11-07 Julien Malzac , Annalisa Celotti

Accreting sources such as AGN, X-ray binaries or gamma-ray bursts are known to be strong, high energy emitters. The hard emission is though to originate from plasmas of thermal and/or non-thermal high energy particles. Not only does this…

Astrophysics · Physics 2008-11-03 R. Belmont , J. Malzac , A. Marcowith

Summary of abstract: The existence of a new population of yet unrecognized x-ray sources has been often suggested to resolve some pecularities in the properties of the x-ray background (XRB), and has recently been indicated by an analysis…

Astrophysics · Physics 2009-10-22 Eyal Maoz , Jonathan Grindlay

Recent analyses of the fluctuations of the soft Diffuse X-ray Background (DXB) have provided indirect detection of a component consistent with the elusive Warm Hot Intergalactic Medium (WHIM). In this work we use theoretical predictions…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Eugenio Ursino , Enzo Branchini , Massimiliano Galeazzi , Federico Marulli , Lauro Moscardini , Luigi Piro , Mauro Roncarelli , Yoh Takei

We have conducted a thorough and blind search for emission lines in >70 Swift X-ray afterglows of total exposure ~10^7s. We find that most afterglows are consistent with pure power-laws plus extinction. Significant outliers to the…

Astrophysics · Physics 2008-11-26 Nathaniel R. Butler

We present the results of a detailed correlation study between the soft X-ray, hard X-ray, and radio emission (obtained from RXTE ASM, BATSE, and GBI observations, respectively) of the bright radio emitting Galactic X-ray binary Cygnus X-3.…

Astrophysics · Physics 2009-11-07 M. Choudhury , A. R. Rao , S. V. Vadawale , C. H. Ishwara-Chandra , A. K. Jain

We present the results of the deepest optically identified X-ray survey yet made. The X-ray survey was made with the ROSAT PSPC and reaches a flux limit of 1.6x10^-15 erg cm^-2 s^-1 (0.5--2.0 keV). Above a flux limit of 2x10^-15 erg cm^-2…

We propose that the X--ray emission from radio quiet AGN and galactic black holes is due to Comptonization of soft thermal photons emitted by the underlying accretion disk in localized structures (blobs). The power per unit area produced by…

Astrophysics · Physics 2009-10-22 Francesco Haardt , Laura Maraschi , Gabriele Ghisellini

We present the first dynamically and thermally self-consistent calculations of fast adiabatically expanding gas flows from the Galactic disk into the halo. It is shown that in a hot plasma (T >= 10^6 K) with a high overpressure with respect…

Astrophysics · Physics 2007-05-23 Dieter Breitschwerdt , Thomas Schmutzler

We discuss the methods used to compile a high signal-to-noise dataset representative of both the instrumental and cosmic background signal measured at high galactic latitude by the XMM-Newton EPIC cameras. The characteristics of the EPIC…

Astrophysics · Physics 2009-11-07 D. H. Lumb , R. S. Warwick , M. Page , A. De Luca

While the cosmic soft X-ray background is very likely to originate from individual Seyfert galaxies, the origin of the cosmic hard X-ray and MeV gamma-ray background is not fully understood. It is expected that Seyferts including Compton…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Yoshiyuki Inoue , Kohta Murase , Grzegorz M. Madejski , Yasunobu Uchiyama

We use simulations to predict the X-ray surface brightness distribution arising from hot, cosmologically distributed diffuse gas. The distribution is computed for two bands: 0.5-2 keV and 0.1-0.4 keV, using a cosmological-constant dominated…

Astrophysics · Physics 2009-11-06 Greg L. Bryan , G. Mark Voit

In this article we review the measurements and understanding of the X-ray background (XRB), discovered by Giacconi and collaborators 35 years ago. We start from the early history and the debate whether the XRB is due to a single,…

Astrophysics · Physics 2007-05-23 Guenther Hasinger , Gianni Zamorani

The diffuse X-ray background (DXB) emission near the Galactic plane ($l,b \sim 25.6^{\circ},0.78^{\circ}$) has been observed with $ASCA$. The observed region is toward a Galactic molecular cloud which was recently reported to cast a deep…

Astrophysics · Physics 2009-10-31 Sangwook Park , Ken Ebisawa

The question of the X-ray background has been largely settled over the last 10 years using the ROSAT satellite. About 70-80 % of the soft X-ray background was resolved into discrete sources, which are mainly X-ray and optically unobscured…

Astrophysics · Physics 2007-05-23 I. Lehmann , G. Hasinger , S. S. Murray , M. Schmidt

Using {\it Herschel}-SPIRE imaging and the Canada-France Imaging Survey (CFIS) Low Surface Brightness data products from the Ultraviolet Near-Infrared Optical Northern Survey (UNIONS), we present a cross-correlation between the cosmic…

Despite the influx of unprecedented-quality data from the Fermi Gamma-Ray Space Telescope that have been collected over nine years of operation, the contribution of normal star-forming galaxies to the extragalactic gamma-ray background…

High Energy Astrophysical Phenomena · Physics 2018-12-19 I. Komis , V. Pavlidou , A. Zezas

The correlation between the soft X-ray and near infrared emission from AGN is analysed using composite models by the code SUMA. We find new evidences for differences in ranges of parameters which characterize the NLR of Seyfert galaxies and…

Astrophysics · Physics 2009-11-10 M. Contini , S. M. Viegas , P. E. Campos