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Related papers: Progress in Understanding the Diffuse UV Cosmic Ba…

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We have searched for diffuse intracluster light in the galaxy cluster Abell 2667 (z=0.233) from HST images in three filters. We have applied to these images an iterative multi-scale wavelet analysis and reconstruction technique, which…

Astrophysics · Physics 2009-11-11 G. Covone , C. Adami , F. Durret , J. -P. Kneib , G. B. Lima Neto , E. Slezak

The Lyman edge at 912 \AA is an important diagnostic region for studying quasi-stellar objects (QSOs). In particular, it reveals a great deal about the physical conditions within the atmospheres of accretion disks, a ubiquitous component of…

Astrophysics · Physics 2009-10-30 Anuradha Koratkar , Robert Antonucci , Robert Goodrich , Alex Storrs

Over the past several decades, advances in telescope/detector technologies and deep imaging techniques have pushed surface brightness limits to ever fainter levels. We can now both detect and measure the diffuse, extended star light that…

Astrophysics of Galaxies · Physics 2019-09-23 J. Christopher Mihos

We present Monte Carlo calculations of Lyman alpha (Lya) radiative transfer through collapsing gas clouds, representing proto-galaxies that are caught in the process of their assembly. Such galaxies produce Lya flux over an extended solid…

Astrophysics · Physics 2008-11-26 Mark Dijkstra , Zoltan Haiman , Marco Spaans

Diffuse Galactic gamma-ray emission is produced in interactions of cosmic rays with gas and ambient photon fields and thus provides us with an indirect measurement of cosmic rays in various locations in the Galaxy. The diffuse gamma-ray…

Astrophysics · Physics 2007-05-23 Martin Pohl

We present the first large, unbiased sample of Lyman Break Galaxies (LBGs) at z ~ 1. Far ultraviolet-dropout (1530 A) galaxies in the Chandra Deep Field South have been selected using GALEX data. This first large sample in the z ~ 1…

We describe the initial results of a deep long-slit emission line search for redshifted (2.7<z<4.1) Lyman-alpha. These observations are used to constrain the fluorescent Ly-alpha emission from the population of clouds whose absorption…

Astrophysics · Physics 2015-06-24 Andrew J. Bunker , Francine R. Marleau , James R. Graham

We present Galaxy Evolution Explorer (GALEX) far-UV and near-UV mosaic observations covering the entirety of M31 and M33. For both targets, we measure the decline of surface brightness (in FUV and NUV) and changes in FUV--NUV color as a…

A detailed knowledge of the Galactic radio continuum is of high interest for studies of the dynamics and structure of the Galaxy as well as for the problem of foreground removal in Cosmic Microwave Background measurements. In this work we…

Astrophysics · Physics 2011-05-23 P. Platania , C. Burigana , D. Maino , E. Caserini , M. Bersanelli , B. Cappellini , A. Mennella

We have used the rocket-borne Wide-Field Imaging Survey Polarimeter (WISP) to image a 1.5 deg. by 4.8 deg. area of the western side of the LMC at a wavelength of 215 nm and a resolution of 1' x 1.5'. These are the first wide-field…

Astrophysics · Physics 2009-10-31 Andrew A. Cole , Kenneth H. Nordsieck , Steven J. Gibson , Walter M. Harris

The origin of the diffuse extragalactic, high-energy gamma-ray background (EGRB) filling the Universe remains unknown. The spectrum of this extragalactic radiation, as measured by the EGRET on-board CGRO, is well-fit by a power law across…

Astrophysics · Physics 2009-11-07 Caleb A. Scharf , Reshmi Mukherjee

We study the observed cosmic ionizing background as a constraint on the nature of the sources responsible for the reionization of the Universe. In earlier work, we showed that extrapolations of the Ultra-Violet Luminosity Function (LF) of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Fabio Fontanot , Stefano Cristiani , Christoph Pfrommer , Guido Cupani , Eros Vanzella

We calibrate here cosmological radiative transfer simulation with ATON/RAMSES with a range of measurements of the Lyman alpha opacity from QSO absorption spectra. We find the Lyman alpha opacity to be very sensitive to the exact timing of…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Jonathan Chardin , Martin G. Haehnelt , Dominique Aubert , Ewald Puchwein

Recent findings by gamma-ray Cherenkov telescopes suggest a higher transparency of the Universe to very-high-energy (VHE) photons than expected from current models of the Extragalactic Background Light. It has been shown that such…

Astrophysics · Physics 2009-12-10 A. De Angelis , O. Mansutti , M. Persic , M. Roncadelli

We explore the possibility that the diffuse gamma-ray background radiation (GBR) at high galactic latitudes could be dominated by inverse Compton scattering of cosmic ray (CR) electrons on the cosmic microwave background radiation and on…

Astrophysics · Physics 2009-10-31 Arnon Dar , A. De Rújula

Some Lyman continuum photons are likely to escape from most galaxies, and these can play an important role in ionizing gas around and between galaxies, including gas that gives rise to Lyman alpha absorption. Thus the gas surrounding…

We searched for star formation activity associated with high-z Damped Lyman-alpha systems (DLAs) with Subaru telescope. We used a set of narrow-band (NB) filters whose central wavelengths correspond to the redshifted Lyman-alpha emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Nobunari Kashikawa , Toru Misawa , Yosuke Minowa , Katsuya Okoshi , Takashi Hattori , Jun Toshikawa , Shogo Ishikawa , Masafusa Onoue

We present a study of the spectral, polarimetric, morphological and environmental properties of the diffuse radio source 0809+39 using observations taken with the Westerbork Synthesis Radio Telescope, the Very Large Array, and archival…

Astrophysics · Physics 2009-11-13 Shea Brown , Lawrence Rudnick

We consider the observation of diffuse halos of light around the discs of spiral galaxies, as a probe of the interaction cross section between Dark Matter and photons. Using the galaxy M101 as an example, we show that for a scattering cross…

High Energy Physics - Phenomenology · Physics 2015-02-05 Jonathan H. Davis , Joseph Silk

We measured the dipole of the diffuse $\gamma$-ray background (DGB) identifying a highly significant time-independent signal coincidental with that of the Pierre Auger UHECR. The DGB dipole is determined from flux maps in narrow energy…

High Energy Astrophysical Phenomena · Physics 2024-01-10 A. Kashlinsky , F. Atrio-Barandela , C. S. Shrader