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Related papers: The Far Ultraviolet Background

200 papers

The ubiquitous diffuse soft (1/4 keV) X-ray background was one of the earliest discoveries of X-ray astronomy. At least some of the emission may arise from charge exchange between solar wind ions and neutral atoms in the heliosphere, but no…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Randall K. Smith , Adam R. Foster , Richard J. Edgar , Nancy S. Brickhouse

The diffuse extragalactic background light consists of the sum of the starlight emitted by galaxies through the history of the Universe, and it could also have an important contribution from the first stars, which may have formed before…

Astrophysics · Physics 2012-08-27 H. E. S. S. Collaboration , : , F. Aharonian

We present the first observations of diffuse radiation in the far ultraviolet (1000 -- 1150 \AA) from the Large Magellanic Cloud based on observations made with the {\it Far Ultraviolet Spectroscopic Explorer}. The fraction of the total…

Astrophysics of Galaxies · Physics 2015-05-19 Ananta C. Pradhan , Amit Pathak , Jayant Murthy

The far-ultraviolet (FUV) diffuse emission is predominantly due to scattering of starlight from interstellar dust grains which shows a large regional variation depending on the relative orientations of dust and stars. The observations of…

Astrophysics of Galaxies · Physics 2013-07-05 Ananta C. Pradhan

In 1992 the Far-Ultraviolet Space Telescope (FAUST) provided measurements of the ultraviolet (140-180nm) diffuse sky background at high, medium, and low Galactic latitudes. A significant fraction of the detected radiation was found to be of…

Astrophysics · Physics 2009-10-30 Adolf N. Witt , Brian C. Friedmann , Timothy P. Sasseen

Observations at long wavelengths, in the wide interval from a few to 1000 micron, are essential to study diffuse media in galaxies, including all kinds of atomic, ionic and molecular gases and dust grains. Hence they are particularly suited…

Astrophysics · Physics 2007-05-23 Alberto Franceschini

When viewed from above the Earth's atmosphere, the nighttime ultraviolet sky background is profoundly dark - up to 100 times fainter than the equivalent visible background as measured by groundbased telescopes. Because the UV background is…

A bright UV GALEX image in the direction of a dense high galactic latitude interstellar dust cloud is examined to test (and to reject) the idea that a bright extragalactic UV background radiation field exists. A GALEX "Deep Imaging Survey"…

Astrophysics of Galaxies · Physics 2009-06-17 Richard Conn Henry

We present a physical model for origin of the cosmic diffuse infrared background (CDIRB). By utilizing the observed stellar mass function and its evolution as input to a semi-empirical model of galaxy formation, we isolate the physics…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Joshua D. Younger , Philip F. Hopkins

Here is reviewed our current understanding of Galactic and extragalactic diffuse gamma-ray emission. The spectrum of the extragalactic gamma-ray background above 30 MeV can be well described by a power law with photon index s=2.1. In the…

Astrophysics · Physics 2007-05-23 Martin Pohl

The first generation of stars (commonly known as population III) are expected to form in low-mass protogalaxies in which molecular hydrogen is the dominant coolant. Radiation from these stars will rapidly build up an extragalactic…

Astrophysics · Physics 2009-11-07 Simon C. O. Glover , Peter W. J. L. Brand

The Galactic gamma-ray flux can be described as the sum of two components: the first is due to the emission from an ensemble of discrete sources, and the second is formed by the photons produced by cosmic rays propagating in interstellar…

High Energy Astrophysical Phenomena · Physics 2024-12-13 Paolo Lipari , Silvia Vernetto

In this paper, we report on a first estimate of the contribution of galaxies to the diffuse extragalactic background from the far-UV to the submm, based on semi--analytic models of galaxy formation and evolution. We conclude that the global…

Astrophysics · Physics 2007-05-23 J. E. G Devriendt , B. Guiderdoni , S. K. Sethi

The launch of the Fermi gamma-ray space telescope and the imaging air Cerenkov telescopes H.E.S.S., MAGIC, and VERITAS have substantially transformed our knowledge of gamma-ray sources in the last decade. The extragalactic gamma-ray sky is…

High Energy Astrophysical Phenomena · Physics 2013-09-02 C. Pfrommer

Rest-frame far-ultraviolet (FUV) luminosities form the `backbone' of our understanding of star formation at all cosmic epochs. These luminosities are typically corrected for dust by assuming that the tight relationship between the UV…

Astrophysics · Physics 2007-05-23 Eric F. Bell

Many recent estimates of the star formation rate density at high redshift rely on rest-frame ultraviolet (UV) data. These are highly sensitive to dust absorption. Applying a correlation between the far-infrared (FIR) to UV flux ratio and UV…

We calculate the contribution to the ultraviolet background (UVB) from thermal emission from gas shock heated by cosmic structure formation. Our main calculation is based on an updated version of Press-Schechter theory. It is consistent…

Astrophysics · Physics 2009-09-25 Francesco Miniati , Andrea Ferrara , Simon D. M. White , Simone Bianchi

It has been recently argued [1-3] that there is a strong component of the diffuse far-ultraviolet (FUV) background which is hard to explain by conventional physics in terms of the dust-scattered starlight. We propose that this excess in FUV…

High Energy Physics - Phenomenology · Physics 2022-03-17 Ariel Zhitnitsky

Inverse Compton scattering by relativistic electrons produces a major component of the diffuse emission from the Galaxy. The photon fields involved are the cosmic microwave background and the interstellar radiation field from stars and…

Astrophysics · Physics 2009-09-29 Elena Orlando , Andrew Strong

The Fermi Gamma-ray Space Telescope has revealed a diffuse $\gamma$-ray background at energies from 0.1 GeV to 1 TeV, which can be separated into Galactic emission and an isotropic, extragalactic component. Previous efforts to understand…

High Energy Astrophysical Phenomena · Physics 2021-09-17 Matt A. Roth , Mark R. Krumholz , Roland M. Crocker , Silvia Celli