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The case for small neutrino mass differences from atmospheric and solar neutrino oscillation experiments has become compelling, but leaves the overall neutrino mass scale m_nu undetermined. The most restrictive limit of m_nu < 0.8 eV arises…

Astrophysics · Physics 2009-11-07 G. G. Raffelt

We investigate the cosmological evolution of the luminosity and redshift of FRBs. As is the case for all extragalactic sources, we are dealing with data that are truncated by observational selection effects, the most important being the…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-05 Sujay Champati , Vahé Petrosian

We discuss the present bounds on the relativistic energy density in the Universe parameterized in terms of the effective number of neutrinos N using the most recent cosmological data on Cosmic Microwave Background (CMB) temperature…

Astrophysics · Physics 2010-10-27 Gianpiero Mangano , Alessandro Melchiorri , Olga Mena , Gennaro Miele , Anze Slosar

Primordial magnetic fields (PMFs), which were generated in the early Universe before recombination, affect the motion of plasma and then the cosmic microwave background and the matter power spectrum. We consider constraints on PMFs with a…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 Dai G. Yamazaki , Kiyotomo Ichiki , Keitaro Takahashi

We place empirical constraints on the physical properties of $\gamma-$ray burst events at cosmological distances. In particular we derive probability distributions for the radiation energy $E_\gamma$, the minimum Lorentz factor $\gamma_{\rm…

Astrophysics · Physics 2016-08-30 Eric Woods , Abraham Loeb

Gamma-ray absorption due to gamma-gamma-pair creation on cosmological scales depends on the line-of-sight integral of the evolving density of low-energy photons in the Universe, i.e. on the history of the diffuse, isotropic radiation field.…

Astrophysics · Physics 2009-11-07 Tanja M. Kneiske , Karl Mannheim , Dieter H. Hartmann

Recent cosmological measurements favour additional relativistic energy density beyond the one provided by the three active neutrinos and photons of the Standard Model (SM). This is often referred to as "dark radiation", suggesting the need…

High Energy Physics - Phenomenology · Physics 2015-06-12 M. C. Gonzalez-Garcia , V. Niro , Jordi Salvado

Properties of CFRS field galaxies up to z=1 are discussed. Estimations of the cosmic star formation rate (SFR) lead to serious problems if they not account for AGN emissions and for light reemitted at IR wavelengths. Deep ISOCAM and VLA…

Astrophysics · Physics 2007-05-23 F. Hammer , H. Flores

We develop and examine the principles governing the formation of distortions in the cosmic microwave background. Distortions in the frequency or spectral distribution of the background probe the thermal history of the universe whereas those…

Astrophysics · Physics 2009-07-17 Wayne Hu

The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history,…

Light thermal relics of the hot big bang, often quantified by the parameter $N_\mathrm{eff}$, are one of the primary targets of cosmological measurements. At present, the energy density in such relics is constrained to be less than ten…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-06 Daniel Baumann , Daniel Green , Benjamin Wallisch

Mankind has not yet explained dark matter, the accelerating expansion of the Universe, the 'knee' and 'ankle' of the cosmic ray energy spectrum graph, the low star formation rates of low surface brightness (LSB) dwarf galaxies, the ignition…

Astrophysics · Physics 2007-05-23 Jerome Drexler

Theoretically, the running of the cosmological constant in the IR region is not ruled out. On the other hand, from the QFT viewpoint, the energy released due to the variation of the cosmological constant in the late universe cannot go to…

General Relativity and Quantum Cosmology · Physics 2020-09-30 Jhonny A. Agudelo Ruiz , Tibério de Paula Netto , Júlio C. Fabris , Ilya L. Shapiro

Observations of neutron stars, whether in binaries or in isolation, provide information about the internal structure of the most extreme material objects in the Universe. In this work, we combine information from recent observations to…

High Energy Astrophysical Phenomena · Physics 2021-08-29 Philippe Landry , Reed Essick , Katerina Chatziioannou

Many extensions of the Standard Model predict large numbers of additional unstable particles whose decays in the early universe are tightly constrained by observational data. For example, the decays of such particles can alter the ratios of…

High Energy Physics - Phenomenology · Physics 2019-02-20 Keith R. Dienes , Jason Kumar , Patrick Stengel , Brooks Thomas

The CMB anisotropy depends sensitively upon the slope and amplitude of primordial density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history, {\it etc.} We report…

Astrophysics · Physics 2009-09-25 J. Richard Bond , Richard L. Davis , Paul J. Steinhardt

We review the physical processes that are thought to produce anisotropy in the cosmic microwave background, focusing primarily (but not exclusively) on the effects of acoustic waves in the early Universe. We attempt throughout to supply an…

Astrophysics · Physics 2007-05-23 Emory F. Bunn

Radio observations of starburst regions in galaxies have revealed groups of compact nonthermal sources that may be radiative supernova remnants expanding in the interclump medium of molecular clouds. Because of the high pressure in…

Astrophysics · Physics 2009-11-06 Roger A. Chevalier , Claes Fransson

The energy spectrum and mass composition of ultra-high energy cosmic rays inferred at the Pierre Auger Observatory are used to derive a benchmark scenario for the emission mechanisms at play in extragalactic accelerators as well as for…

High Energy Astrophysical Phenomena · Physics 2022-12-15 Antonio Condorelli , Quentin Luce , Sullivan Marafico , Jonathan Biteau , Olivier Deligny

This work presents a detailed analysis of Cosmic Microwave Background (CMB) radiation intensity observations. The CMB is a relic of the Big Bang and its study greatly enhances our knowledge of cosmology. This work has led to new values for…

Astrophysics · Physics 2007-05-23 Henrik P. Nordberg , George F. Smoot
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