English
Related papers

Related papers: The Far Ultraviolet Background

200 papers

Diffuse emission in gamma-rays and neutrinos are produced by the interaction of cosmic rays with the interstellar medium. Below some hundreds of TeV, the sources of these cosmic rays are most likely Galactic. Hence, observations of…

High Energy Astrophysical Phenomena · Physics 2025-09-25 Anton Stall , Philipp Mertsch

We have modeled the diffuse background at the Galactic Poles in the far-ultraviolet (FUV: 1536 \AA) and the near-ultraviolet (NUV: 2316 \AA). The background is well-fit using a single-scattering dust model with an offset representing the…

Astrophysics of Galaxies · Physics 2023-09-06 Jayant Murthy , Richard C. Henry , James Overduin

We present a map of the diffuse ultraviolet cosmic background in two wavelength bands (FUV: 1530 {\AA}; NUV: 2310 {\AA}) over almost 75% of the sky using archival data from the GALEX mission. Most of the diffuse flux is due to…

Astrophysics of Galaxies · Physics 2010-11-30 Jayant Murthy , Richard C. Henry , N. V. Sujatha

Rest-frame far-ultraviolet (FUV) luminosities form the `backbone' of our understanding of star formation at all cosmic epochs. FUV luminosities are typically corrected for dust by assuming that extinction indicators which have been…

Astrophysics · Physics 2009-11-07 Eric F. Bell

Assuming a spherical symmetry, the extreme UV emitted by a very hot source ionizes low pressure molecular hydrogen making a transparent bubble of H II (Protons and electrons). For an increase of radius, intensity of extreme UV and…

General Physics · Physics 2007-07-23 Jacques Moret-Bailly

Thermal and chemical evolution of primordial gas clouds irradiated with far-ultraviolet (FUV; < 13.6 eV) radiation is investigated. In clouds irradiated by intense FUV radiation, sufficient hydrogen molecules to be important for cooling are…

Astrophysics · Physics 2009-10-31 Kazuyuki Omukai

The cosmic infrared background (CIB) radiation was a long-sought fossil of energetic processes associated with structure formation and chemical evolution since the Big Bang. The COBE Diffuse Infrared Background Experiment (DIRBE) and Far…

Astrophysics · Physics 2007-05-23 M. G. Hauser

The Cosmic Background due to the integrated radiation from galaxies over the whole life of the Universe is reviewed. We find that this background is well constrained by measurements. The total power in the background is in the range 60-93…

Astrophysics · Physics 2007-05-23 R. Gispert , G. Lagache , J. L. Puget

We have tried to determine the flux of the ultraviolet background radiation field from the column density ratios of various ions in several absorption systems observed in the spectra of QSOs. We find that in most cases the flux is…

Astrophysics · Physics 2009-10-31 Archana Samantaray , Pushpa Khare

In the powerful, high redshift radio galaxies, it is believed that the dominant source of ionization for the interstellar gas is the hard radiation field associated with the active nucleus. The photon source is generally external to the…

Astrophysics · Physics 2007-05-23 M. Villar-Martin , L. Binette , R. A. E. Fosbury

Blazar emission of gamma rays and cosmic ray production of gamma rays in gas-rich clusters have been proposed recently as alternative sources of the high energy extragalactic diffuse gamma ray background radiation. We show that these…

Astrophysics · Physics 2014-10-13 Arnon Dar , Nir J. Shaviv

The determination of the densities of intergalactic photons from the FIR to the UV produced by stellar emission and dust reradiation at various redshifts can provide an independent measure of the star formation history of the universe. High…

Astrophysics · Physics 2007-05-23 F. W. Stecker

The origin of the diffuse extragalactic gamma-ray background, which was measured with the large area telescope (LAT) aboard the Fermi satellite at energy below 820 GeV, and of the diffuse cosmic background of neutrinos, which was observed…

High Energy Astrophysical Phenomena · Physics 2015-05-21 Shlomo Dado , Arnon Dar

We present spectra of the diffuse FUV (900 -- 1200 \AA) emission from a region near the Orion Nebula: the first high resolution spectra of the diffuse background radiation. These observations were made using serendipitous FUSE observations…

Astrophysics · Physics 2009-11-10 Jayant Murthy , David J. Sahnow , R. C. Henry

The cosmic gamma-ray background radiation is one of the most fundamental observables in the gamma-ray band. Although the origin of the cosmic gamma-ray background radiation has been a mystery for a long time, the Fermi gamma-ray space…

High Energy Astrophysical Phenomena · Physics 2014-12-15 Yoshiyuki Inoue

Star forming galaxies have long been considered the dominant sources of the cosmic ultraviolet background radiation at early epochs. However, observing and characterizing the galaxy population with significant ionizing emission has proven…

Astrophysics of Galaxies · Physics 2017-04-12 J. Japelj , E. Vanzella , F. Fontanot , S. Cristiani , G. B. Caminha , P. Tozzi , I. Balestra , P. Rosati , M. Meneghetti

We present images from the Solar Blind Channel on HST that resolve hundreds of far ultraviolet (FUV) emitting stars in two ~1 kpc$^2$ interarm regions of the grand-design spiral M101. The luminosity functions of these stars are compared…

We have studied the diffuse radiation in the surroundings of M42 using photometric data from the Galaxy Evolution Explorer (GALEX) in the far-ultraviolet (FUV) and infrared observations of the AKARI space telescope. The main source of the…

Astrophysics of Galaxies · Physics 2018-03-21 Gautam Saikia , P. Shalima , Rupjyoti Gogoi

The diffuse far-ultraviolet (FUV) continuum radiation "longward" of Ly-alpha (1216A) is well known to correlate with the dust emission at 100 um. However, it has been claimed that the FUV continuum background "shortward" of Ly-alpha shows…

Astrophysics of Galaxies · Physics 2015-06-16 Kwang-Il Seon

The propagation of particles accelerated at supernova remnant shocks and escaping the parent remnants is likely to proceed in a strongly non-linear regime, due to the efficient self-generation of Alfv\'en waves excited through streaming…

High Energy Astrophysical Phenomena · Physics 2017-12-27 M. D'Angelo , G. Morlino , E. Amato , P. Blasi