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Related papers: The Case for Dark Radiation

200 papers

We use large-scale cosmological observations to place constraints on the dark-matter pressure, sound speed and viscosity, and infer a limit on the mass of warm-dark-matter particles. Measurements of the cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-08 Martin Kunz , Savvas Nesseris , Ignacy Sawicki

Using the latest AMS-02 cosmic ray antiproton flux data, we search for potential dark matter annihilation signal. The background parameters about the propagation, source injection, and solar modulation are not assumed {\it a priori}, but…

High Energy Astrophysical Phenomena · Physics 2017-05-17 Ming-Yang Cui , Qiang Yuan , Yue-Lin Sming Tsai , Yi-Zhong Fan

In this letter, the effects of dark radiation (DR) are tested. Theoretically, the phase-space analysis method is applied to check whether the model is consist with the history of our universe which shows positive results. Observationally,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Yi Zhang , Yungui Gong

Interest in light dark matter candidates has recently increased in the literature; some of these works consider the role of additional neutrinos, either active or sterile. Furthermore, extragalactic neutrinos have been detected with…

High Energy Physics - Phenomenology · Physics 2015-03-27 O. G. Miranda , C. A. Moura , A. Parada

We examine how the properties of dark matter, parameterised by an equation of state parameter $w$ and two perturbative Generalised Dark Matter (GDM) parameters $c^2_s$ (the sound speed) and $c^2_\text{vis}$ (the viscosity), are constrained…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-04 Daniel B. Thomas , Michael Kopp , Constantinos Skordis

There are compelling evidences for the existence of a fourth degree of freedom of neutrinos i.e. sterile neutrino. In the recent studies the role of sterile component of neutrinos has been found to be crucial, not only in particle physics,…

High Energy Physics - Phenomenology · Physics 2019-04-12 Ankush , Rishu Verma , Gazal Sharma , B. C. Chauhan

We constrain the neutrino properties in $f(R)$ gravity using the latest observations from cosmic microwave background(CMB) and baryon acoustic oscillation(BAO) measurements. We first constrain separately the total mass of neutrinos $\sum…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-25 Jian-hua He

Recent analyses that include cosmic microwave background (CMB) anisotropy measurements from the Atacama Cosmology Telescope and the South Pole Telescope have hinted at the presence of a dark radiation component at more than two standard…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Erminia Calabrese , Maria Archidiacono , Alessandro Melchiorri , Bharat Ratra

We constrain the evolution of the dark energy density from Cosmic Microwave Background, Large Scale Structure and Supernovae Ia measurements. While Supernovae Ia are most sensitive to the equation of state $w_0$ of dark energy today, the…

Astrophysics · Physics 2009-11-13 Michael Doran , Khamphee Karwan , Christof Wetterich

Despite direct observations favoring a low mass density, a critical density universe with a neutrino component of dark matter provides the best existing model to explain the observed structure of the universe over more than three orders of…

Astrophysics · Physics 2009-10-31 David O. Caldwell

Calculations of the cosmic rate of core collapses, and the associated neutrino flux, commonly assume that a fixed fraction of massive stars collapse to black holes. We argue that recent results suggest that this fraction instead increases…

High Energy Astrophysical Phenomena · Physics 2015-11-23 Hasan Yuksel , Matthew D. Kistler

We perform a detailed forecast on how well a {\sc Euclid}-like survey will be able to constrain dark energy and neutrino parameters from a combination of its cosmic shear power spectrum, galaxy power spectrum, and cluster mass function…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Tobias Basse , Ole Eggers Bjaelde , Jan Hamann , Steen Hannestad , Yvonne Y. Y. Wong

We explore the possibility that exotic forms of dark matter could expose humans on Earth or on prolonged space travel to a significant radiation dose. The radiation exposure from dark matter interacting with nuclei in the human body is…

High Energy Physics - Phenomenology · Physics 2025-05-26 Florian Niedermann , Martin S. Sloth

We use the currently available cosmic observations to probe and constrain an imperfect dark energy fluid which is characterized by a constant equation of state $w$ and a constant speed of viscosity $c^2_{vis}$. The model parameter space was…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Baorong Chang , Lixin Xu

Cosmic strings, topological defects predicted by high-energy theories, may contribute to the late-time expansion of the Universe, effectively mimicking dynamical dark energy. We investigate four phenomenological extensions of the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-06 Hanyu Cheng , Eleonora Di Valentino , Luca Visinelli

Neutrino self-interactions beyond the standard model have profound implications in astrophysics and cosmology. In this Letter, we study an uncharted scenario in which one of the three neutrino species has a mass smaller than the temperature…

High Energy Physics - Phenomenology · Physics 2025-10-30 Isaac R. Wang , Xun-Jie Xu , Bei Zhou

The characterisation of dark energy is one of the primary goals in cosmology especially now that many new experiments are being planned with the aim of reaching a high sensitivity on cosmological parameters. It is known that if we move away…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Domenico Sapone , Elisabetta Majerotto

This short review was prepared as an introduction to the Royal Society's 'Dark Matter' conference. It addresses the embarrassing fact that 95% of the universe is unaccounted for. Favoured dark matter candidates are axions or…

Astrophysics · Physics 2010-12-09 Martin J. Rees

We look for evidence for the evolution in dark energy density by employing Principal Component Analysis (PCA). Distance redshift data from supernovae and baryon acoustic oscillations (BAO) along with WMAP7 distance priors are used to put…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Remya Nair , Sanjay Jhingan

Recent studies by a number of independent collaborations, have correlated the CMB temperatures measured by the WMAP satellite with different galaxy surveys that trace the matter distribution with light from the whole range of the…

Astrophysics · Physics 2009-11-10 E. Gaztanaga , M. Manera , T. Multamaki