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Related papers: Metagalactic Ultraviolet Flux from Cosmic Structur…

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We report the results of J-band infrared spectroscopy of a sample of 13 z=1 field galaxies drawn from the Canada-France Redshift Survey, targeting galaxies whose redshifts place the rest frame H-alpha line emission from HII regions in…

Astrophysics · Physics 2009-10-30 Karl Glazebrook , Chris Blake , Frossie Economou , Simon Lilly , Matthew Colless

Since the discovery of the Ultraviolet Upturn Phenomenon (``UVX'') in early-type galaxies it has been clear that the stellar populations of such systems contain an unexpected hot component. Recent work has provided strong circumstantial…

Astrophysics · Physics 2007-05-23 Ben Dorman

Recent observations suggest that hydrogen reionization ends late ($z \simeq 6$) and proceeds quickly. We present here a new model of the meta-galactic UV/X-ray background (UVB) that is consistent with this. It adopts the most recent…

Astrophysics of Galaxies · Physics 2019-01-30 Ewald Puchwein , Francesco Haardt , Martin G. Haehnelt , Piero Madau

We investigate large-scale galactic winds driven by momentum deposition. Momentum injection is provided by (1) radiation pressure produced by the continuum absorption and scattering of UV photons on dust grains and (2) supernovae. UV…

Astrophysics · Physics 2009-11-10 Norman Murray , Eliot Quataert , Todd A. Thompson

Starlight from galaxies plays a pivotal role throughout the process of cosmic reionisation. We present the statistics of dwarf galaxy properties at z > 7 in haloes with masses up to 10^9 solar masses, using a cosmological radiation…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-08 John H. Wise , Vasiliy G. Demchenko , Martin T. Halicek , Michael L. Norman , Matthew J. Turk , Tom Abel , Britton D. Smith

Cosmic structure originated from minute density perturbations in an almost homogeneous universe. The first stars are believed to be very massive and luminous, providing the first ionizing radiation and heavy elements to the universe and…

Astrophysics · Physics 2008-04-28 John H. Wise

The Milky Way hosts astrophysical accelerators capable of producing high-energy cosmic rays. These cosmic rays can interact with the interstellar medium (ISM) across the Galaxy to produce neutrinos and gamma rays (propagation component),…

High Energy Astrophysical Phenomena · Physics 2026-02-17 Mohadeseh Ozlati Moghadam , Kathrin Egberts , Rowan Batzofin , Constantin Steppa , Elisa Bernardini

We present $[OIII]/H_{\rm \beta}$ emision line flux ratio predictions for galaxies at $z \sim 7-9$ using the MAPPINGS V v5.2.0 photoionization modelling code combined with an analytic galaxy formation model. Properties such as pressure and…

Astrophysics of Galaxies · Physics 2025-04-08 Aadarsh Pathak , J. Stuart B. Wyithe , Ralph S. Sutherland , L. J Kewley

We study the evolution of the galaxy UV luminosity density as a function of redshift in the Hubble Deep Field North (HDF-N). We estimate the amount of energy absorbed by dust and hidden from optical observations by analyzing the HDF-N…

Astrophysics · Physics 2016-08-30 M. Massarotti , A. Iovino , A. Buzzoni

Observations of high-z galaxies and gamma-ray bursts now allow for empirical studies during reionization. However, even deep surveys see only the brightest galaxies at any epoch and must extrapolate to arbitrary lower limits to estimate the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-09 Matthew D. Kistler , Hasan Yuksel , Andrew M. Hopkins

We find that the amount and nature of the assumed ionizing background can strongly affect galaxy formation and evolution. Galaxy evolution simulations typically incorporate an ultraviolet background which falls off rapidly above z=3; e.g.,…

Astrophysics of Galaxies · Physics 2014-11-20 D. Clay Hambrick , Jeremiah P. Ostriker , Thorsten Naab , Peter H. Johansson

We use cosmological simulations from the Feedback In Realistic Environments (FIRE) project, which implement a comprehensive set of stellar feedback processes, to study ultra-violet (UV) metal line emission from the circum-galactic medium of…

The Galactic diffuse gamma-ray emission is conventionally modeled as the product of cosmic-ray interactions with the interstellar medium. However, the cumulative contribution of stellar atmospheres acting as hadronic interaction targets…

High Energy Astrophysical Phenomena · Physics 2026-04-14 Yanbo Wang , Zhenglong Wang , Rui Zhang , Yi Zhang

The diffuse ultraviolet background radiation has been mapped over most of the sky with 2\arcmin \ resolution using data from the \textit{GALEX} survey. We utilize this map to study the correlation between the UV background and clusters of…

Astrophysics of Galaxies · Physics 2020-05-27 Brian Welch , Stephan McCandliss , Dan Coe

[Abridged] We present a physical model for the evolution of the ultraviolet (UV) luminosity function (LF) of high-z galaxies taking into account in a self-consistent way their chemical evolution and the associated evolution of dust…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-31 Zhen-Yi Cai , Andrea Lapi , Alessandro Bressan , Gianfranco De Zotti , Mattia Negrello , Luigi Danese

We carry out direct numerical simulations of turbulent astrophysical media exposed to the redshift zero metagalactic background. The simulations assume solar composition and explicitly track ionizations, recombinations, and ion-by-ion…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-16 William J Gray , Evan Scannapieco

The formation of the first generations of stars at redshifts z > 15-20 signaled the transition from the simple initial state of the universe to one of increasing complexity. We here review recent progress in understanding the assembly…

Astrophysics · Physics 2009-11-13 Jarrett L. Johnson , Thomas H. Greif , Volker Bromm

Models and simulations of the epoch of reionization predict that spectra of the 21-cm transition of atomic hydrogen will show a clear fluctuation peak, at a redshift and scale, respectively, that mark the central stage of reionization and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Anastasia Fialkov , Rennan Barkana , Eli Visbal

The detection of a HeII absorption trough in the spectra of three high-redshift quasars provides new constraints on the spectral shape of the UV extragalactic background. The relative strengths of the observed flux decrements at the…

Astrophysics · Physics 2007-05-23 Francesco Haardt , Piero Madau

One attractive scenario for the excess of sub-PeV/PeV neutrinos recently reported by IceCube is that they are produced by cosmic rays in starburst galaxies colliding with the dense interstellar medium. These proton-proton ($pp$) collisions…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Xiao-Chuan Chang , Xiang-Yu Wang
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